Guile NEWS --- history of user-visible changes. Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. See the end for copying conditions. Please send Guile bug reports to bug-guile@gnu.org. Note that you must be subscribed to this list first, in order to successfully send a report to it. Each release reports the NEWS in the following sections: * Changes to the distribution * Changes to the stand-alone interpreter * Changes to Scheme functions and syntax * Changes to the C interface Changes in 1.9.XXXXXXXX: * Changes to the distribution * Changes to the stand-alone interpreter * Changes to Scheme functions and syntax * Changes to the C interface ** Functions for handling scm_option now no longer require an argument indicating length of the scm_t_option array. Changes in 1.8.2 (since 1.8.1): * New procedures (see the manual for details) ** set-program-arguments * Bugs fixed ** Fractions were not `equal?' if stored in unreduced form. (A subtle problem, since printing a value reduced it, making it work.) ** srfi-60 `copy-bit' failed on 64-bit systems ** "guile --use-srfi" option at the REPL can replace core functions (Programs run with that option were ok, but in the interactive REPL the core bindings got priority, preventing SRFI replacements or extensions.) ** `regexp-exec' doesn't abort() on #\nul in the input or bad flags arg ** `kill' on mingw throws an error for a pid other than oneself ** Procedure names are attached to procedure-with-setters ** Array read syntax works with negative lower bound ** `array-in-bounds?' fix if an array has different lower bounds on each index ** `*' returns exact 0 for "(* inexact 0)" This follows what it always did for "(* 0 inexact)". ** Build problems on Solaris fixed ** Build problems on Mingw fixed Changes in 1.8.1 (since 1.8.0): * LFS functions are now used to access 64-bit files on 32-bit systems. * New procedures (see the manual for details) ** primitive-_exit - [Scheme] the-root-module ** scm_primitive__exit - [C] ** make-completion-function - [Scheme] (ice-9 readline) ** scm_c_locale_stringn_to_number - [C] ** scm_srfi1_append_reverse [C] ** scm_srfi1_append_reverse_x [C] ** scm_log - [C] ** scm_log10 - [C] ** scm_exp - [C] ** scm_sqrt - [C] * New `(ice-9 i18n)' module (see the manual for details) * Bugs fixed ** Build problems have been fixed on MacOS, SunOS, and QNX. ** A one-dimensional array can now be 'equal?' to a vector. ** Structures, records, and SRFI-9 records can now be compared with `equal?'. ** SRFI-14 standard char sets are recomputed upon a successful `setlocale'. ** `record-accessor' and `record-modifier' now have strict type checks. Record accessor and modifier procedures now throw an error if the record type of the record they're given is not the type expected. (Previously accessors returned #f and modifiers silently did nothing). ** It is now OK to use both autoload and use-modules on a given module. ** `apply' checks the number of arguments more carefully on "0 or 1" funcs. Previously there was no checking on primatives like make-vector that accept "one or two" arguments. Now there is. ** The srfi-1 assoc function now calls its equality predicate properly. Previously srfi-1 assoc would call the equality predicate with the key last. According to the SRFI, the key should be first. ** A bug in n-par-for-each and n-for-each-par-map has been fixed. ** The array-set! procedure no longer segfaults when given a bit vector. ** Bugs in make-shared-array have been fixed. ** stringinexact should no longer overflow when given certain large fractions. ** srfi-9 accessor and modifier procedures now have strict record type checks. This matches the srfi-9 specification. ** (ice-9 ftw) procedures won't ignore different files with same inode number. Previously the (ice-9 ftw) procedures would ignore any file that had the same inode number as a file they had already seen, even if that file was on a different device. Changes in 1.8.0 (changes since the 1.6.x series): * Changes to the distribution ** Guile is now licensed with the GNU Lesser General Public License. ** The manual is now licensed with the GNU Free Documentation License. ** Guile now requires GNU MP (http://swox.com/gmp). Guile now uses the GNU MP library for arbitrary precision arithmetic. ** Guile now has separate private and public configuration headers. That is, things like HAVE_STRING_H no longer leak from Guile's headers. ** Guile now provides and uses an "effective" version number. Guile now provides scm_effective_version and effective-version functions which return the "effective" version number. This is just the normal full version string without the final micro-version number, so the current effective-version is "1.8". The effective version should remain unchanged during a stable series, and should be used for items like the versioned share directory name i.e. /usr/share/guile/1.8. Providing an unchanging version number during a stable release for things like the versioned share directory can be particularly important for Guile "add-on" packages, since it provides a directory that they can install to that won't be changed out from under them with each micro release during a stable series. ** Thread implementation has changed. When you configure "--with-threads=null", you will get the usual threading API (call-with-new-thread, make-mutex, etc), but you can't actually create new threads. Also, "--with-threads=no" is now equivalent to "--with-threads=null". This means that the thread API is always present, although you might not be able to create new threads. When you configure "--with-threads=pthreads" or "--with-threads=yes", you will get threads that are implemented with the portable POSIX threads. These threads can run concurrently (unlike the previous "coop" thread implementation), but need to cooperate for things like the GC. The default is "pthreads", unless your platform doesn't have pthreads, in which case "null" threads are used. See the manual for details, nodes "Initialization", "Multi-Threading", "Blocking", and others. ** There is the new notion of 'discouraged' features. This is a milder form of deprecation. Things that are discouraged should not be used in new code, but it is OK to leave them in old code for now. When a discouraged feature is used, no warning message is printed like there is for 'deprecated' features. Also, things that are merely discouraged are nevertheless implemented efficiently, while deprecated features can be very slow. You can omit discouraged features from libguile by configuring it with the '--disable-discouraged' option. ** Deprecation warnings can be controlled at run-time. (debug-enable 'warn-deprecated) switches them on and (debug-disable 'warn-deprecated) switches them off. ** Support for SRFI 61, extended cond syntax for multiple values has been added. This SRFI is always available. ** Support for require-extension, SRFI-55, has been added. The SRFI-55 special form `require-extension' has been added. It is available at startup, and provides a portable way to load Scheme extensions. SRFI-55 only requires support for one type of extension, "srfi"; so a set of SRFIs may be loaded via (require-extension (srfi 1 13 14)). ** New module (srfi srfi-26) provides support for `cut' and `cute'. The (srfi srfi-26) module is an implementation of SRFI-26 which provides the `cut' and `cute' syntax. These may be used to specialize parameters without currying. ** New module (srfi srfi-31) This is an implementation of SRFI-31 which provides a special form `rec' for recursive evaluation. ** The modules (srfi srfi-13), (srfi srfi-14) and (srfi srfi-4) have been merged with the core, making their functionality always available. The modules are still available, tho, and you could use them together with a renaming import, for example. ** Guile no longer includes its own version of libltdl. The official version is good enough now. ** The --enable-htmldoc option has been removed from 'configure'. Support for translating the documentation into HTML is now always provided. Use 'make html'. ** New module (ice-9 serialize): (serialize FORM1 ...) and (parallelize FORM1 ...) are useful when you don't trust the thread safety of most of your program, but where you have some section(s) of code which you consider can run in parallel to other sections. See ice-9/serialize.scm for more information. ** The configure option '--disable-arrays' has been removed. Support for arrays and uniform numeric arrays is now always included in Guile. * Changes to the stand-alone interpreter ** New command line option `-L'. This option adds a directory to the front of the load path. ** New command line option `--no-debug'. Specifying `--no-debug' on the command line will keep the debugging evaluator turned off, even for interactive sessions. ** User-init file ~/.guile is now loaded with the debugging evaluator. Previously, the normal evaluator would have been used. Using the debugging evaluator gives better error messages. ** The '-e' option now 'read's its argument. This is to allow the new '(@ MODULE-NAME VARIABLE-NAME)' construct to be used with '-e'. For example, you can now write a script like #! /bin/sh exec guile -e '(@ (demo) main)' -s "$0" "$@" !# (define-module (demo) :export (main)) (define (main args) (format #t "Demo: ~a~%" args)) * Changes to Scheme functions and syntax ** Guardians have changed back to their original semantics Guardians now behave like described in the paper by Dybvig et al. In particular, they no longer make guarantees about the order in which they return objects, and they can no longer be greedy. They no longer drop cyclic data structures. The C function scm_make_guardian has been changed incompatibly and no longer takes the 'greedy_p' argument. ** New function hashx-remove! This function completes the set of 'hashx' functions. ** The concept of dynamic roots has been factored into continuation barriers and dynamic states. Each thread has a current dynamic state that carries the values of the fluids. You can create and copy dynamic states and use them as the second argument for 'eval'. See "Fluids and Dynamic States" in the manual. To restrict the influence that captured continuations can have on the control flow, you can errect continuation barriers. See "Continuation Barriers" in the manual. The function call-with-dynamic-root now essentially temporarily installs a new dynamic state and errects a continuation barrier. ** The default load path no longer includes "." at the end. Automatically loading modules from the current directory should not happen by default. If you want to allow it in a more controlled manner, set the environment variable GUILE_LOAD_PATH or the Scheme variable %load-path. ** The uniform vector and array support has been overhauled. It now complies with SRFI-4 and the weird prototype based uniform array creation has been deprecated. See the manual for more details. Some non-compatible changes have been made: - characters can no longer be stored into byte arrays. - strings and bit vectors are no longer considered to be uniform numeric vectors. - array-rank throws an error for non-arrays instead of returning zero. - array-ref does no longer accept non-arrays when no indices are given. There is the new notion of 'generalized vectors' and corresponding procedures like 'generalized-vector-ref'. Generalized vectors include strings, bitvectors, ordinary vectors, and uniform numeric vectors. Arrays use generalized vectors as their storage, so that you still have arrays of characters, bits, etc. However, uniform-array-read! and uniform-array-write can no longer read/write strings and bitvectors. ** There is now support for copy-on-write substrings, mutation-sharing substrings and read-only strings. Three new procedures are related to this: substring/shared, substring/copy, and substring/read-only. See the manual for more information. ** Backtraces will now highlight the value that caused the error. By default, these values are enclosed in "{...}", such as in this example: guile> (car 'a) Backtrace: In current input: 1: 0* [car {a}] :1:1: In procedure car in expression (car (quote a)): :1:1: Wrong type (expecting pair): a ABORT: (wrong-type-arg) The prefix and suffix used for highlighting can be set via the two new printer options 'highlight-prefix' and 'highlight-suffix'. For example, putting this into ~/.guile will output the bad value in bold on an ANSI terminal: (print-set! highlight-prefix "\x1b[1m") (print-set! highlight-suffix "\x1b[22m") ** 'gettext' support for internationalization has been added. See the manual for details. ** New syntax '@' and '@@': You can now directly refer to variables exported from a module by writing (@ MODULE-NAME VARIABLE-NAME) For example (@ (ice-9 pretty-print) pretty-print) will directly access the pretty-print variable exported from the (ice-9 pretty-print) module. You don't need to 'use' that module first. You can also use '@' as a target of 'set!', as in (set! (@ mod var) val). The related syntax (@@ MODULE-NAME VARIABLE-NAME) works just like '@', but it can also access variables that have not been exported. It is intended only for kluges and temporary fixes and for debugging, not for ordinary code. ** Keyword syntax has been made more disciplined. Previously, the name of a keyword was read as a 'token' but printed as a symbol. Now, it is read as a general Scheme datum which must be a symbol. Previously: guile> #:12 #:#{12}# guile> #:#{12}# #:#{\#{12}\#}# guile> #:(a b c) #:#{}# ERROR: In expression (a b c): Unbound variable: a guile> #: foo #:#{}# ERROR: Unbound variable: foo Now: guile> #:12 ERROR: Wrong type (expecting symbol): 12 guile> #:#{12}# #:#{12}# guile> #:(a b c) ERROR: Wrong type (expecting symbol): (a b c) guile> #: foo #:foo ** The printing of symbols that might look like keywords can be controlled. The new printer option 'quote-keywordish-symbols' controls how symbols are printed that have a colon as their first or last character. The default now is to only quote a symbol with #{...}# when the read option 'keywords' is not '#f'. Thus: guile> (define foo (string->symbol ":foo")) guile> (read-set! keywords #f) guile> foo :foo guile> (read-set! keywords 'prefix) guile> foo #{:foo}# guile> (print-set! quote-keywordish-symbols #f) guile> foo :foo ** 'while' now provides 'break' and 'continue' break and continue were previously bound in a while loop, but not documented, and continue didn't quite work properly. The undocumented parameter to break which gave a return value for the while has been dropped. ** 'call-with-current-continuation' is now also available under the name 'call/cc'. ** The module system now checks for duplicate bindings. The module system now can check for name conflicts among imported bindings. The behavior can be controlled by specifying one or more 'duplicates' handlers. For example, to make Guile return an error for every name collision, write: (define-module (foo) :use-module (bar) :use-module (baz) :duplicates check) The new default behavior of the module system when a name collision has been detected is to 1. Give priority to bindings marked as a replacement. 2. Issue a warning (different warning if overriding core binding). 3. Give priority to the last encountered binding (this corresponds to the old behavior). If you want the old behavior back without replacements or warnings you can add the line: (default-duplicate-binding-handler 'last) to your .guile init file. ** New define-module option: :replace :replace works as :export, but, in addition, marks the binding as a replacement. A typical example is `format' in (ice-9 format) which is a replacement for the core binding `format'. ** Adding prefixes to imported bindings in the module system There is now a new :use-module option :prefix. It can be used to add a prefix to all imported bindings. (define-module (foo) :use-module ((bar) :prefix bar:)) will import all bindings exported from bar, but rename them by adding the prefix `bar:'. ** Conflicting generic functions can be automatically merged. When two imported bindings conflict and they are both generic functions, the two functions can now be merged automatically. This is activated with the 'duplicates' handler 'merge-generics'. ** New function: effective-version Returns the "effective" version number. This is just the normal full version string without the final micro-version number. See "Changes to the distribution" above. ** New threading functions: parallel, letpar, par-map, and friends These are convenient ways to run calculations in parallel in new threads. See "Parallel forms" in the manual for details. ** New function 'try-mutex'. This function will attempt to lock a mutex but will return immediately instead of blocking and indicate failure. ** Waiting on a condition variable can have a timeout. The function 'wait-condition-variable' now takes a third, optional argument that specifies the point in time where the waiting should be aborted. ** New function 'broadcast-condition-variable'. ** New functions 'all-threads' and 'current-thread'. ** Signals and system asyncs work better with threads. The function 'sigaction' now takes a fourth, optional, argument that specifies the thread that the handler should run in. When the argument is omitted, the handler will run in the thread that called 'sigaction'. Likewise, 'system-async-mark' takes a second, optional, argument that specifies the thread that the async should run in. When it is omitted, the async will run in the thread that called 'system-async-mark'. C code can use the new functions scm_sigaction_for_thread and scm_system_async_mark_for_thread to pass the new thread argument. When a thread blocks on a mutex, a condition variable or is waiting for IO to be possible, it will still execute system asyncs. This can be used to interrupt such a thread by making it execute a 'throw', for example. ** The function 'system-async' is deprecated. You can now pass any zero-argument procedure to 'system-async-mark'. The function 'system-async' will just return its argument unchanged now. ** New functions 'call-with-blocked-asyncs' and 'call-with-unblocked-asyncs' The expression (call-with-blocked-asyncs PROC) will call PROC and will block execution of system asyncs for the current thread by one level while PROC runs. Likewise, call-with-unblocked-asyncs will call a procedure and will unblock the execution of system asyncs by one level for the current thread. Only system asyncs are affected by these functions. ** The functions 'mask-signals' and 'unmask-signals' are deprecated. Use 'call-with-blocked-asyncs' or 'call-with-unblocked-asyncs' instead. Those functions are easier to use correctly and can be nested. ** New function 'unsetenv'. ** New macro 'define-syntax-public'. It works like 'define-syntax' and also exports the defined macro (but only on top-level). ** There is support for Infinity and NaNs. Following PLT Scheme, Guile can now work with infinite numbers, and 'not-a-numbers'. There is new syntax for numbers: "+inf.0" (infinity), "-inf.0" (negative infinity), "+nan.0" (not-a-number), and "-nan.0" (same as "+nan.0"). These numbers are inexact and have no exact counterpart. Dividing by an inexact zero returns +inf.0 or -inf.0, depending on the sign of the dividend. The infinities are integers, and they answer #t for both 'even?' and 'odd?'. The +nan.0 value is not an integer and is not '=' to itself, but '+nan.0' is 'eqv?' to itself. For example (/ 1 0.0) => +inf.0 (/ 0 0.0) => +nan.0 (/ 0) ERROR: Numerical overflow Two new predicates 'inf?' and 'nan?' can be used to test for the special values. ** Inexact zero can have a sign. Guile can now distinguish between plus and minus inexact zero, if your platform supports this, too. The two zeros are equal according to '=', but not according to 'eqv?'. For example (- 0.0) => -0.0 (= 0.0 (- 0.0)) => #t (eqv? 0.0 (- 0.0)) => #f ** Guile now has exact rationals. Guile can now represent fractions such as 1/3 exactly. Computing with them is also done exactly, of course: (* 1/3 3/2) => 1/2 ** 'floor', 'ceiling', 'round' and 'truncate' now return exact numbers for exact arguments. For example: (floor 2) now returns an exact 2 where in the past it returned an inexact 2.0. Likewise, (floor 5/4) returns an exact 1. ** inexact->exact no longer returns only integers. Without exact rationals, the closest exact number was always an integer, but now inexact->exact returns the fraction that is exactly equal to a floating point number. For example: (inexact->exact 1.234) => 694680242521899/562949953421312 When you want the old behavior, use 'round' explicitly: (inexact->exact (round 1.234)) => 1 ** New function 'rationalize'. This function finds a simple fraction that is close to a given real number. For example (and compare with inexact->exact above): (rationalize (inexact->exact 1.234) 1/2000) => 58/47 Note that, as required by R5RS, rationalize returns only then an exact result when both its arguments are exact. ** 'odd?' and 'even?' work also for inexact integers. Previously, (odd? 1.0) would signal an error since only exact integers were recognized as integers. Now (odd? 1.0) returns #t, (odd? 2.0) returns #f and (odd? 1.5) signals an error. ** Guile now has uninterned symbols. The new function 'make-symbol' will return an uninterned symbol. This is a symbol that is unique and is guaranteed to remain unique. However, uninterned symbols can not yet be read back in. Use the new function 'symbol-interned?' to check whether a symbol is interned or not. ** pretty-print has more options. The function pretty-print from the (ice-9 pretty-print) module can now also be invoked with keyword arguments that control things like maximum output width. See the manual for details. ** Variables have no longer a special behavior for `equal?'. Previously, comparing two variables with `equal?' would recursivly compare their values. This is no longer done. Variables are now only `equal?' if they are `eq?'. ** `(begin)' is now valid. You can now use an empty `begin' form. It will yield # when evaluated and simply be ignored in a definition context. ** Deprecated: procedure->macro Change your code to use 'define-macro' or r5rs macros. Also, be aware that macro expansion will not be done during evaluation, but prior to evaluation. ** Soft ports now allow a `char-ready?' procedure The vector argument to `make-soft-port' can now have a length of either 5 or 6. (Previously the length had to be 5.) The optional 6th element is interpreted as an `input-waiting' thunk -- i.e. a thunk that returns the number of characters that can be read immediately without the soft port blocking. ** Deprecated: undefine There is no replacement for undefine. ** The functions make-keyword-from-dash-symbol and keyword-dash-symbol have been discouraged. They are relics from a time where a keyword like #:foo was used directly as a Tcl option "-foo" and thus keywords were internally stored as a symbol with a starting dash. We now store a symbol without the dash. Use symbol->keyword and keyword->symbol instead. ** The `cheap' debug option is now obsolete Evaluator trap calls are now unconditionally "cheap" - in other words, they pass a debug object to the trap handler rather than a full continuation. The trap handler code can capture a full continuation by using `call-with-current-continuation' in the usual way, if it so desires. The `cheap' option is retained for now so as not to break existing code which gets or sets it, but setting it now has no effect. It will be removed in the next major Guile release. ** Evaluator trap calls now support `tweaking' `Tweaking' means that the trap handler code can modify the Scheme expression that is about to be evaluated (in the case of an enter-frame trap) or the value that is being returned (in the case of an exit-frame trap). The trap handler code indicates that it wants to do this by returning a pair whose car is the symbol 'instead and whose cdr is the modified expression or return value. * Changes to the C interface ** The functions scm_hash_fn_remove_x and scm_hashx_remove_x no longer take a 'delete' function argument. This argument makes no sense since the delete function is used to remove a pair from an alist, and this must not be configurable. This is an incompatible change. ** The GH interface is now subject to the deprecation mechanism The GH interface has been deprecated for quite some time but now it is actually removed from Guile when it is configured with --disable-deprecated. See the manual "Transitioning away from GH" for more information. ** A new family of functions for converting between C values and Scheme values has been added. These functions follow a common naming scheme and are designed to be easier to use, thread-safe and more future-proof than the older alternatives. - int scm_is_* (...) These are predicates that return a C boolean: 1 or 0. Instead of SCM_NFALSEP, you can now use scm_is_true, for example. - scm_to_ (SCM val, ...) These are functions that convert a Scheme value into an appropriate C value. For example, you can use scm_to_int to safely convert from a SCM to an int. - SCM scm_from_ ( val, ...) These functions convert from a C type to a SCM value; for example, scm_from_int for ints. There is a huge number of these functions, for numbers, strings, symbols, vectors, etc. They are documented in the reference manual in the API section together with the types that they apply to. ** New functions for dealing with complex numbers in C have been added. The new functions are scm_c_make_rectangular, scm_c_make_polar, scm_c_real_part, scm_c_imag_part, scm_c_magnitude and scm_c_angle. They work like scm_make_rectangular etc but take or return doubles directly. ** The function scm_make_complex has been discouraged. Use scm_c_make_rectangular instead. ** The INUM macros have been deprecated. A lot of code uses these macros to do general integer conversions, although the macros only work correctly with fixnums. Use the following alternatives. SCM_INUMP -> scm_is_integer or similar SCM_NINUMP -> !scm_is_integer or similar SCM_MAKINUM -> scm_from_int or similar SCM_INUM -> scm_to_int or similar SCM_VALIDATE_INUM_* -> Do not use these; scm_to_int, etc. will do the validating for you. ** The scm_num2 and scm_2num functions and scm_make_real have been discouraged. Use the newer scm_to_ and scm_from_ functions instead for new code. The functions have been discouraged since they don't fit the naming scheme. ** The 'boolean' macros SCM_FALSEP etc have been discouraged. They have strange names, especially SCM_NFALSEP, and SCM_BOOLP evaluates its argument twice. Use scm_is_true, etc. instead for new code. ** The macro SCM_EQ_P has been discouraged. Use scm_is_eq for new code, which fits better into the naming conventions. ** The macros SCM_CONSP, SCM_NCONSP, SCM_NULLP, and SCM_NNULLP have been discouraged. Use the function scm_is_pair or scm_is_null instead. ** The functions scm_round and scm_truncate have been deprecated and are now available as scm_c_round and scm_c_truncate, respectively. These functions occupy the names that scm_round_number and scm_truncate_number should have. ** The functions scm_c_string2str, scm_c_substring2str, and scm_c_symbol2str have been deprecated. Use scm_to_locale_stringbuf or similar instead, maybe together with scm_substring. ** New functions scm_c_make_string, scm_c_string_length, scm_c_string_ref, scm_c_string_set_x, scm_c_substring, scm_c_substring_shared, scm_c_substring_copy. These are like scm_make_string, scm_length, etc. but are slightly easier to use from C. ** The macros SCM_STRINGP, SCM_STRING_CHARS, SCM_STRING_LENGTH, SCM_SYMBOL_CHARS, and SCM_SYMBOL_LENGTH have been deprecated. They export too many assumptions about the implementation of strings and symbols that are no longer true in the presence of mutation-sharing substrings and when Guile switches to some form of Unicode. When working with strings, it is often best to use the normal string functions provided by Guile, such as scm_c_string_ref, scm_c_string_set_x, scm_string_append, etc. Be sure to look in the manual since many more such functions are now provided than previously. When you want to convert a SCM string to a C string, use the scm_to_locale_string function or similar instead. For symbols, use scm_symbol_to_string and then work with that string. Because of the new string representation, scm_symbol_to_string does not need to copy and is thus quite efficient. ** Some string, symbol and keyword functions have been discouraged. They don't fit into the uniform naming scheme and are not explicit about the character encoding. Replace according to the following table: scm_allocate_string -> scm_c_make_string scm_take_str -> scm_take_locale_stringn scm_take0str -> scm_take_locale_string scm_mem2string -> scm_from_locale_stringn scm_str2string -> scm_from_locale_string scm_makfrom0str -> scm_from_locale_string scm_mem2symbol -> scm_from_locale_symboln scm_mem2uninterned_symbol -> scm_from_locale_stringn + scm_make_symbol scm_str2symbol -> scm_from_locale_symbol SCM_SYMBOL_HASH -> scm_hashq SCM_SYMBOL_INTERNED_P -> scm_symbol_interned_p scm_c_make_keyword -> scm_from_locale_keyword ** The functions scm_keyword_to_symbol and sym_symbol_to_keyword are now also available to C code. ** SCM_KEYWORDP and SCM_KEYWORDSYM have been deprecated. Use scm_is_keyword and scm_keyword_to_symbol instead, but note that the latter returns the true name of the keyword, not the 'dash name', as SCM_KEYWORDSYM used to do. ** A new way to access arrays in a thread-safe and efficient way has been added. See the manual, node "Accessing Arrays From C". ** The old uniform vector and bitvector implementations have been unceremoniously removed. This implementation exposed the details of the tagging system of Guile. Use the new C API explained in the manual in node "Uniform Numeric Vectors" and "Bit Vectors", respectively. The following macros are gone: SCM_UVECTOR_BASE, SCM_SET_UVECTOR_BASE, SCM_UVECTOR_MAXLENGTH, SCM_UVECTOR_LENGTH, SCM_MAKE_UVECTOR_TAG, SCM_SET_UVECTOR_LENGTH, SCM_BITVECTOR_P, SCM_BITVECTOR_BASE, SCM_SET_BITVECTOR_BASE, SCM_BITVECTOR_MAX_LENGTH, SCM_BITVECTOR_LENGTH, SCM_MAKE_BITVECTOR_TAG, SCM_SET_BITVECTOR_LENGTH, SCM_BITVEC_REF, SCM_BITVEC_SET, SCM_BITVEC_CLR. ** The macros dealing with vectors have been deprecated. Use the new functions scm_is_vector, scm_vector_elements, scm_vector_writable_elements, etc, or scm_is_simple_vector, SCM_SIMPLE_VECTOR_REF, SCM_SIMPLE_VECTOR_SET, etc instead. See the manual for more details. Deprecated are SCM_VECTORP, SCM_VELTS, SCM_VECTOR_MAX_LENGTH, SCM_VECTOR_LENGTH, SCM_VECTOR_REF, SCM_VECTOR_SET, SCM_WRITABLE_VELTS. The following macros have been removed: SCM_VECTOR_BASE, SCM_SET_VECTOR_BASE, SCM_MAKE_VECTOR_TAG, SCM_SET_VECTOR_LENGTH, SCM_VELTS_AS_STACKITEMS, SCM_SETVELTS, SCM_GC_WRITABLE_VELTS. ** Some C functions and macros related to arrays have been deprecated. Migrate according to the following table: scm_make_uve -> scm_make_typed_array, scm_make_u8vector etc. scm_make_ra -> scm_make_array scm_shap2ra -> scm_make_array scm_cvref -> scm_c_generalized_vector_ref scm_ra_set_contp -> do not use scm_aind -> scm_array_handle_pos scm_raprin1 -> scm_display or scm_write SCM_ARRAYP -> scm_is_array SCM_ARRAY_NDIM -> scm_c_array_rank SCM_ARRAY_DIMS -> scm_array_handle_dims SCM_ARRAY_CONTP -> do not use SCM_ARRAY_MEM -> do not use SCM_ARRAY_V -> scm_array_handle_elements or similar SCM_ARRAY_BASE -> do not use ** SCM_CELL_WORD_LOC has been deprecated. Use the new macro SCM_CELL_OBJECT_LOC instead, which returns a pointer to a SCM, as opposed to a pointer to a scm_t_bits. This was done to allow the correct use of pointers into the Scheme heap. Previously, the heap words were of type scm_t_bits and local variables and function arguments were of type SCM, making it non-standards-conformant to have a pointer that can point to both. ** New macros SCM_SMOB_DATA_2, SCM_SMOB_DATA_3, etc. These macros should be used instead of SCM_CELL_WORD_2/3 to access the second and third words of double smobs. Likewise for SCM_SET_SMOB_DATA_2 and SCM_SET_SMOB_DATA_3. Also, there is SCM_SMOB_FLAGS and SCM_SET_SMOB_FLAGS that should be used to get and set the 16 exra bits in the zeroth word of a smob. And finally, there is SCM_SMOB_OBJECT and SCM_SMOB_SET_OBJECT for accesing the first immediate word of a smob as a SCM value, and there is SCM_SMOB_OBJECT_LOC for getting a pointer to the first immediate smob word. Like wise for SCM_SMOB_OBJECT_2, etc. ** New way to deal with non-local exits and re-entries. There is a new set of functions that essentially do what scm_internal_dynamic_wind does, but in a way that is more convenient for C code in some situations. Here is a quick example of how to prevent a potential memory leak: void foo () { char *mem; scm_dynwind_begin (0); mem = scm_malloc (100); scm_dynwind_unwind_handler (free, mem, SCM_F_WIND_EXPLICITLY); /* MEM would leak if BAR throws an error. SCM_DYNWIND_UNWIND_HANDLER frees it nevertheless. */ bar (); scm_dynwind_end (); /* Because of SCM_F_WIND_EXPLICITLY, MEM will be freed by SCM_DYNWIND_END as well. */ } For full documentation, see the node "Dynamic Wind" in the manual. ** New function scm_dynwind_free This function calls 'free' on a given pointer when a dynwind context is left. Thus the call to scm_dynwind_unwind_handler above could be replaced with simply scm_dynwind_free (mem). ** New functions scm_c_call_with_blocked_asyncs and scm_c_call_with_unblocked_asyncs Like scm_call_with_blocked_asyncs etc. but for C functions. ** New functions scm_dynwind_block_asyncs and scm_dynwind_unblock_asyncs In addition to scm_c_call_with_blocked_asyncs you can now also use scm_dynwind_block_asyncs in a 'dynwind context' (see above). Likewise for scm_c_call_with_unblocked_asyncs and scm_dynwind_unblock_asyncs. ** The macros SCM_DEFER_INTS, SCM_ALLOW_INTS, SCM_REDEFER_INTS, SCM_REALLOW_INTS have been deprecated. They do no longer fulfill their original role of blocking signal delivery. Depending on what you want to achieve, replace a pair of SCM_DEFER_INTS and SCM_ALLOW_INTS with a dynwind context that locks a mutex, blocks asyncs, or both. See node "Critical Sections" in the manual. ** The value 'scm_mask_ints' is no longer writable. Previously, you could set scm_mask_ints directly. This is no longer possible. Use scm_c_call_with_blocked_asyncs and scm_c_call_with_unblocked_asyncs instead. ** New way to temporarily set the current input, output or error ports C code can now use scm_dynwind_current__port in a 'dynwind context' (see above). is one of "input", "output" or "error". ** New way to temporarily set fluids C code can now use scm_dynwind_fluid in a 'dynwind context' (see above) to temporarily set the value of a fluid. ** New types scm_t_intmax and scm_t_uintmax. On platforms that have them, these types are identical to intmax_t and uintmax_t, respectively. On other platforms, they are identical to the largest integer types that Guile knows about. ** The functions scm_unmemocopy and scm_unmemoize have been removed. You should not have used them. ** Many public #defines with generic names have been made private. #defines with generic names like HAVE_FOO or SIZEOF_FOO have been made private or renamed with a more suitable public name. ** The macro SCM_TYP16S has been deprecated. This macro is not intended for public use. ** The macro SCM_SLOPPY_INEXACTP has been deprecated. Use scm_is_true (scm_inexact_p (...)) instead. ** The macro SCM_SLOPPY_REALP has been deprecated. Use scm_is_real instead. ** The macro SCM_SLOPPY_COMPLEXP has been deprecated. Use scm_is_complex instead. ** Some preprocessor defines have been deprecated. These defines indicated whether a certain feature was present in Guile or not. Going forward, assume that the features are always present. The macros are: USE_THREADS, GUILE_ISELECT, READER_EXTENSIONS, DEBUG_EXTENSIONS, DYNAMIC_LINKING. The following macros have been removed completely: MEMOIZE_LOCALS, SCM_RECKLESS, SCM_CAUTIOUS. ** The preprocessor define STACK_DIRECTION has been deprecated. There should be no need to know about the stack direction for ordinary programs. ** New function: scm_effective_version Returns the "effective" version number. This is just the normal full version string without the final micro-version number. See "Changes to the distribution" above. ** The function scm_call_with_new_thread has a new prototype. Instead of taking a list with the thunk and handler, these two arguments are now passed directly: SCM scm_call_with_new_thread (SCM thunk, SCM handler); This is an incompatible change. ** New snarfer macro SCM_DEFINE_PUBLIC. This is like SCM_DEFINE, but also calls scm_c_export for the defined function in the init section. ** The snarfer macro SCM_SNARF_INIT is now officially supported. ** Garbage collector rewrite. The garbage collector is cleaned up a lot, and now uses lazy sweeping. This is reflected in the output of (gc-stats); since cells are being freed when they are allocated, the cells-allocated field stays roughly constant. For malloc related triggers, the behavior is changed. It uses the same heuristic as the cell-triggered collections. It may be tuned with the environment variables GUILE_MIN_YIELD_MALLOC. This is the percentage for minimum yield of malloc related triggers. The default is 40. GUILE_INIT_MALLOC_LIMIT sets the initial trigger for doing a GC. The default is 200 kb. Debugging operations for the freelist have been deprecated, along with the C variables that control garbage collection. The environment variables GUILE_MAX_SEGMENT_SIZE, GUILE_INIT_SEGMENT_SIZE_2, GUILE_INIT_SEGMENT_SIZE_1, and GUILE_MIN_YIELD_2 should be used. For understanding the memory usage of a GUILE program, the routine gc-live-object-stats returns an alist containing the number of live objects for every type. ** The function scm_definedp has been renamed to scm_defined_p The name scm_definedp is deprecated. ** The struct scm_cell type has been renamed to scm_t_cell This is in accordance to Guile's naming scheme for types. Note that the name scm_cell is now used for a function that allocates and initializes a new cell (see below). ** New functions for memory management A new set of functions for memory management has been added since the old way (scm_must_malloc, scm_must_free, etc) was error prone and indeed, Guile itself contained some long standing bugs that could cause aborts in long running programs. The new functions are more symmetrical and do not need cooperation from smob free routines, among other improvements. The new functions are scm_malloc, scm_realloc, scm_calloc, scm_strdup, scm_strndup, scm_gc_malloc, scm_gc_calloc, scm_gc_realloc, scm_gc_free, scm_gc_register_collectable_memory, and scm_gc_unregister_collectable_memory. Refer to the manual for more details and for upgrading instructions. The old functions for memory management have been deprecated. They are: scm_must_malloc, scm_must_realloc, scm_must_free, scm_must_strdup, scm_must_strndup, scm_done_malloc, scm_done_free. ** Declarations of exported features are marked with SCM_API. Every declaration of a feature that belongs to the exported Guile API has been marked by adding the macro "SCM_API" to the start of the declaration. This macro can expand into different things, the most common of which is just "extern" for Unix platforms. On Win32, it can be used to control which symbols are exported from a DLL. If you `#define SCM_IMPORT' before including , SCM_API will expand into "__declspec (dllimport) extern", which is needed for linking to the Guile DLL in Windows. There are also SCM_RL_IMPORT, SCM_SRFI1314_IMPORT, and SCM_SRFI4_IMPORT, for the corresponding libraries. ** SCM_NEWCELL and SCM_NEWCELL2 have been deprecated. Use the new functions scm_cell and scm_double_cell instead. The old macros had problems because with them allocation and initialization was separated and the GC could sometimes observe half initialized cells. Only careful coding by the user of SCM_NEWCELL and SCM_NEWCELL2 could make this safe and efficient. ** CHECK_ENTRY, CHECK_APPLY and CHECK_EXIT have been deprecated. Use the variables scm_check_entry_p, scm_check_apply_p and scm_check_exit_p instead. ** SRCBRKP has been deprecated. Use scm_c_source_property_breakpoint_p instead. ** Deprecated: scm_makmacro Change your code to use either scm_makmmacro or to define macros in Scheme, using 'define-macro'. ** New function scm_c_port_for_each. This function is like scm_port_for_each but takes a pointer to a C function as the callback instead of a SCM value. ** The names scm_internal_select, scm_thread_sleep, and scm_thread_usleep have been discouraged. Use scm_std_select, scm_std_sleep, scm_std_usleep instead. ** The GC can no longer be blocked. The global flags scm_gc_heap_lock and scm_block_gc have been removed. The GC can now run (partially) concurrently with other code and thus blocking it is not well defined. ** Many definitions have been removed that were previously deprecated. scm_lisp_nil, scm_lisp_t, s_nil_ify, scm_m_nil_ify, s_t_ify, scm_m_t_ify, s_0_cond, scm_m_0_cond, s_0_ify, scm_m_0_ify, s_1_ify, scm_m_1_ify, scm_debug_newcell, scm_debug_newcell2, scm_tc16_allocated, SCM_SET_SYMBOL_HASH, SCM_IM_NIL_IFY, SCM_IM_T_IFY, SCM_IM_0_COND, SCM_IM_0_IFY, SCM_IM_1_IFY, SCM_GC_SET_ALLOCATED, scm_debug_newcell, scm_debug_newcell2, SCM_HUP_SIGNAL, SCM_INT_SIGNAL, SCM_FPE_SIGNAL, SCM_BUS_SIGNAL, SCM_SEGV_SIGNAL, SCM_ALRM_SIGNAL, SCM_GC_SIGNAL, SCM_TICK_SIGNAL, SCM_SIG_ORD, SCM_ORD_SIG, SCM_NUM_SIGS, scm_top_level_lookup_closure_var, *top-level-lookup-closure*, scm_system_transformer, scm_eval_3, scm_eval2, root_module_lookup_closure, SCM_SLOPPY_STRINGP, SCM_RWSTRINGP, scm_read_only_string_p, scm_make_shared_substring, scm_tc7_substring, sym_huh, SCM_VARVCELL, SCM_UDVARIABLEP, SCM_DEFVARIABLEP, scm_mkbig, scm_big2inum, scm_adjbig, scm_normbig, scm_copybig, scm_2ulong2big, scm_dbl2big, scm_big2dbl, SCM_FIXNUM_BIT, SCM_SETCHARS, SCM_SLOPPY_SUBSTRP, SCM_SUBSTR_STR, SCM_SUBSTR_OFFSET, SCM_LENGTH_MAX, SCM_SETLENGTH, SCM_ROSTRINGP, SCM_ROLENGTH, SCM_ROCHARS, SCM_ROUCHARS, SCM_SUBSTRP, SCM_COERCE_SUBSTR, scm_sym2vcell, scm_intern, scm_intern0, scm_sysintern, scm_sysintern0, scm_sysintern0_no_module_lookup, scm_init_symbols_deprecated, scm_vector_set_length_x, scm_contregs, scm_debug_info, scm_debug_frame, SCM_DSIDEVAL, SCM_CONST_LONG, SCM_VCELL, SCM_GLOBAL_VCELL, SCM_VCELL_INIT, SCM_GLOBAL_VCELL_INIT, SCM_HUGE_LENGTH, SCM_VALIDATE_STRINGORSUBSTR, SCM_VALIDATE_ROSTRING, SCM_VALIDATE_ROSTRING_COPY, SCM_VALIDATE_NULLORROSTRING_COPY, SCM_VALIDATE_RWSTRING, DIGITS, scm_small_istr2int, scm_istr2int, scm_istr2flo, scm_istring2number, scm_istr2int, scm_istr2flo, scm_istring2number, scm_vtable_index_vcell, scm_si_vcell, SCM_ECONSP, SCM_NECONSP, SCM_GLOC_VAR, SCM_GLOC_VAL, SCM_GLOC_SET_VAL, SCM_GLOC_VAL_LOC, scm_make_gloc, scm_gloc_p, scm_tc16_variable, SCM_CHARS, SCM_LENGTH, SCM_SET_STRING_CHARS, SCM_SET_STRING_LENGTH. * Changes to bundled modules ** (ice-9 debug) Using the (ice-9 debug) module no longer automatically switches Guile to use the debugging evaluator. If you want to switch to the debugging evaluator (which is needed for backtrace information if you hit an error), please add an explicit "(debug-enable 'debug)" to your code just after the code to use (ice-9 debug). Changes since Guile 1.4: * Changes to the distribution ** A top-level TODO file is included. ** Guile now uses a versioning scheme similar to that of the Linux kernel. Guile now always uses three numbers to represent the version, i.e. "1.6.5". The first number, 1, is the major version number, the second number, 6, is the minor version number, and the third number, 5, is the micro version number. Changes in major version number indicate major changes in Guile. Minor version numbers that are even denote stable releases, and odd minor version numbers denote development versions (which may be unstable). The micro version number indicates a minor sub-revision of a given MAJOR.MINOR release. In keeping with the new scheme, (minor-version) and scm_minor_version no longer return everything but the major version number. They now just return the minor version number. Two new functions (micro-version) and scm_micro_version have been added to report the micro version number. In addition, ./GUILE-VERSION now defines GUILE_MICRO_VERSION. ** New preprocessor definitions are available for checking versions. version.h now #defines SCM_MAJOR_VERSION, SCM_MINOR_VERSION, and SCM_MICRO_VERSION to the appropriate integer values. ** Guile now actively warns about deprecated features. The new configure option `--enable-deprecated=LEVEL' and the environment variable GUILE_WARN_DEPRECATED control this mechanism. See INSTALL and README for more information. ** Guile is much more likely to work on 64-bit architectures. Guile now compiles and passes "make check" with only two UNRESOLVED GC cases on Alpha and ia64 based machines now. Thanks to John Goerzen for the use of a test machine, and thanks to Stefan Jahn for ia64 patches. ** New functions: setitimer and getitimer. These implement a fairly direct interface to the libc functions of the same name. ** The #. reader extension is now disabled by default. For safety reasons, #. evaluation is disabled by default. To re-enable it, set the fluid read-eval? to #t. For example: (fluid-set! read-eval? #t) but make sure you realize the potential security risks involved. With read-eval? enabled, reading a data file from an untrusted source can be dangerous. ** New SRFI modules have been added: SRFI-0 `cond-expand' is now supported in Guile, without requiring using a module. (srfi srfi-1) is a library containing many useful pair- and list-processing procedures. (srfi srfi-2) exports and-let*. (srfi srfi-4) implements homogeneous numeric vector datatypes. (srfi srfi-6) is a dummy module for now, since guile already provides all of the srfi-6 procedures by default: open-input-string, open-output-string, get-output-string. (srfi srfi-8) exports receive. (srfi srfi-9) exports define-record-type. (srfi srfi-10) exports define-reader-ctor and implements the reader extension #,(). (srfi srfi-11) exports let-values and let*-values. (srfi srfi-13) implements the SRFI String Library. (srfi srfi-14) implements the SRFI Character-Set Library. (srfi srfi-17) implements setter and getter-with-setter and redefines some accessor procedures as procedures with getters. (such as car, cdr, vector-ref etc.) (srfi srfi-19) implements the SRFI Time/Date Library. ** New scripts / "executable modules" Subdirectory "scripts" contains Scheme modules that are packaged to also be executable as scripts. At this time, these scripts are available: display-commentary doc-snarf generate-autoload punify read-scheme-source use2dot See README there for more info. These scripts can be invoked from the shell with the new program "guile-tools", which keeps track of installation directory for you. For example: $ guile-tools display-commentary srfi/*.scm guile-tools is copied to the standard $bindir on "make install". ** New module (ice-9 stack-catch): stack-catch is like catch, but saves the current state of the stack in the fluid the-last-stack. This fluid can be useful when using the debugger and when re-throwing an error. ** The module (ice-9 and-let*) has been renamed to (ice-9 and-let-star) This has been done to prevent problems on lesser operating systems that can't tolerate `*'s in file names. The exported macro continues to be named `and-let*', of course. On systems that support it, there is also a compatibility module named (ice-9 and-let*). It will go away in the next release. ** New modules (oop goops) etc.: (oop goops) (oop goops describe) (oop goops save) (oop goops active-slot) (oop goops composite-slot) The Guile Object Oriented Programming System (GOOPS) has been integrated into Guile. For further information, consult the GOOPS manual and tutorial in the `doc' directory. ** New module (ice-9 rdelim). This exports the following procedures which were previously defined in the default environment: read-line read-line! read-delimited read-delimited! %read-delimited! %read-line write-line For backwards compatibility the definitions are still imported into the default environment in this version of Guile. However you should add: (use-modules (ice-9 rdelim)) to any program which uses the definitions, since this may change in future. Alternatively, if guile-scsh is installed, the (scsh rdelim) module can be used for similar functionality. ** New module (ice-9 rw) This is a subset of the (scsh rw) module from guile-scsh. Currently it defines two procedures: *** New function: read-string!/partial str [port_or_fdes [start [end]]] Read characters from a port or file descriptor into a string STR. A port must have an underlying file descriptor -- a so-called fport. This procedure is scsh-compatible and can efficiently read large strings. *** New function: write-string/partial str [port_or_fdes [start [end]]] Write characters from a string STR to a port or file descriptor. A port must have an underlying file descriptor -- a so-called fport. This procedure is mostly compatible and can efficiently write large strings. ** New module (ice-9 match) This module includes Andrew K. Wright's pattern matcher. See ice-9/match.scm for brief description or http://www.star-lab.com/wright/code.html for complete documentation. ** New module (ice-9 buffered-input) This module provides procedures to construct an input port from an underlying source of input that reads and returns its input in chunks. The underlying input source is a Scheme procedure, specified by the caller, which the port invokes whenever it needs more input. This is useful when building an input port whose back end is Readline or a UI element such as the GtkEntry widget. ** Documentation The reference and tutorial documentation that was previously distributed separately, as `guile-doc', is now included in the core Guile distribution. The documentation consists of the following manuals. - The Guile Tutorial (guile-tut.texi) contains a tutorial introduction to using Guile. - The Guile Reference Manual (guile.texi) contains (or is intended to contain) reference documentation on all aspects of Guile. - The GOOPS Manual (goops.texi) contains both tutorial-style and reference documentation for using GOOPS, Guile's Object Oriented Programming System. - The Revised^5 Report on the Algorithmic Language Scheme (r5rs.texi). See the README file in the `doc' directory for more details. ** There are a couple of examples in the examples/ directory now. * Changes to the stand-alone interpreter ** New command line option `--use-srfi' Using this option, SRFI modules can be loaded on startup and be available right from the beginning. This makes programming portable Scheme programs easier. The option `--use-srfi' expects a comma-separated list of numbers, each representing a SRFI number to be loaded into the interpreter before starting evaluating a script file or the REPL. Additionally, the feature identifier for the loaded SRFIs is recognized by `cond-expand' when using this option. Example: $ guile --use-srfi=8,13 guile> (receive (x z) (values 1 2) (+ 1 2)) 3 guile> (string-pad "bla" 20) " bla" ** Guile now always starts up in the `(guile-user)' module. Previously, scripts executed via the `-s' option would run in the `(guile)' module and the repl would run in the `(guile-user)' module. Now every user action takes place in the `(guile-user)' module by default. * Changes to Scheme functions and syntax ** Character classifiers work for non-ASCII characters. The predicates `char-alphabetic?', `char-numeric?', `char-whitespace?', `char-lower?', `char-upper?' and `char-is-both?' no longer check whether their arguments are ASCII characters. Previously, a character would only be considered alphabetic when it was also ASCII, for example. ** Previously deprecated Scheme functions have been removed: tag - no replacement. fseek - replaced by seek. list* - replaced by cons*. ** It's now possible to create modules with controlled environments Example: (use-modules (ice-9 safe)) (define m (make-safe-module)) ;;; m will now be a module containing only a safe subset of R5RS (eval '(+ 1 2) m) --> 3 (eval 'load m) --> ERROR: Unbound variable: load ** Evaluation of "()", the empty list, is now an error. Previously, the expression "()" evaluated to the empty list. This has been changed to signal a "missing expression" error. The correct way to write the empty list as a literal constant is to use quote: "'()". ** New concept of `Guile Extensions'. A Guile Extension is just a ordinary shared library that can be linked at run-time. We found it advantageous to give this simple concept a dedicated name to distinguish the issues related to shared libraries from the issues related to the module system. *** New function: load-extension Executing (load-extension lib init) is mostly equivalent to (dynamic-call init (dynamic-link lib)) except when scm_register_extension has been called previously. Whenever appropriate, you should use `load-extension' instead of dynamic-link and dynamic-call. *** New C function: scm_c_register_extension This function registers a initialization function for use by `load-extension'. Use it when you don't want specific extensions to be loaded as shared libraries (for example on platforms that don't support dynamic linking). ** Auto-loading of compiled-code modules is deprecated. Guile used to be able to automatically find and link a shared library to satisfy requests for a module. For example, the module `(foo bar)' could be implemented by placing a shared library named "foo/libbar.so" (or with a different extension) in a directory on the load path of Guile. This has been found to be too tricky, and is no longer supported. The shared libraries are now called "extensions". You should now write a small Scheme file that calls `load-extension' to load the shared library and initialize it explicitly. The shared libraries themselves should be installed in the usual places for shared libraries, with names like "libguile-foo-bar". For example, place this into a file "foo/bar.scm" (define-module (foo bar)) (load-extension "libguile-foo-bar" "foobar_init") ** Backward incompatible change: eval EXP ENVIRONMENT-SPECIFIER `eval' is now R5RS, that is it takes two arguments. The second argument is an environment specifier, i.e. either (scheme-report-environment 5) (null-environment 5) (interaction-environment) or any module. ** The module system has been made more disciplined. The function `eval' will save and restore the current module around the evaluation of the specified expression. While this expression is evaluated, `(current-module)' will now return the right module, which is the module specified as the second argument to `eval'. A consequence of this change is that `eval' is not particularly useful when you want allow the evaluated code to change what module is designated as the current module and have this change persist from one call to `eval' to the next. The read-eval-print-loop is an example where `eval' is now inadequate. To compensate, there is a new function `primitive-eval' that does not take a module specifier and that does not save/restore the current module. You should use this function together with `set-current-module', `current-module', etc when you want to have more control over the state that is carried from one eval to the next. Additionally, it has been made sure that forms that are evaluated at the top level are always evaluated with respect to the current module. Previously, subforms of top-level forms such as `begin', `case', etc. did not respect changes to the current module although these subforms are at the top-level as well. To prevent strange behavior, the forms `define-module', `use-modules', `use-syntax', and `export' have been restricted to only work on the top level. The forms `define-public' and `defmacro-public' only export the new binding on the top level. They behave just like `define' and `defmacro', respectively, when they are used in a lexical environment. Also, `export' will no longer silently re-export bindings imported from a used module. It will emit a `deprecation' warning and will cease to perform any re-export in the next version. If you actually want to re-export bindings, use the new `re-export' in place of `export'. The new `re-export' will not make copies of variables when rexporting them, as `export' did wrongly. ** Module system now allows selection and renaming of imported bindings Previously, when using `use-modules' or the `#:use-module' clause in the `define-module' form, all the bindings (association of symbols to values) for imported modules were added to the "current module" on an as-is basis. This has been changed to allow finer control through two new facilities: selection and renaming. You can now select which of the imported module's bindings are to be visible in the current module by using the `:select' clause. This clause also can be used to rename individual bindings. For example: ;; import all bindings no questions asked (use-modules (ice-9 common-list)) ;; import four bindings, renaming two of them; ;; the current module sees: every some zonk-y zonk-n (use-modules ((ice-9 common-list) :select (every some (remove-if . zonk-y) (remove-if-not . zonk-n)))) You can also programmatically rename all selected bindings using the `:renamer' clause, which specifies a proc that takes a symbol and returns another symbol. Because it is common practice to use a prefix, we now provide the convenience procedure `symbol-prefix-proc'. For example: ;; import four bindings, renaming two of them specifically, ;; and all four w/ prefix "CL:"; ;; the current module sees: CL:every CL:some CL:zonk-y CL:zonk-n (use-modules ((ice-9 common-list) :select (every some (remove-if . zonk-y) (remove-if-not . zonk-n)) :renamer (symbol-prefix-proc 'CL:))) ;; import four bindings, renaming two of them specifically, ;; and all four by upcasing. ;; the current module sees: EVERY SOME ZONK-Y ZONK-N (define (upcase-symbol sym) (string->symbol (string-upcase (symbol->string sym)))) (use-modules ((ice-9 common-list) :select (every some (remove-if . zonk-y) (remove-if-not . zonk-n)) :renamer upcase-symbol)) Note that programmatic renaming is done *after* individual renaming. Also, the above examples show `use-modules', but the same facilities are available for the `#:use-module' clause of `define-module'. See manual for more info. ** The semantics of guardians have changed. The changes are for the most part compatible. An important criterion was to keep the typical usage of guardians as simple as before, but to make the semantics safer and (as a result) more useful. *** All objects returned from guardians are now properly alive. It is now guaranteed that any object referenced by an object returned from a guardian is alive. It's now impossible for a guardian to return a "contained" object before its "containing" object. One incompatible (but probably not very important) change resulting from this is that it is no longer possible to guard objects that indirectly reference themselves (i.e. are parts of cycles). If you do so accidentally, you'll get a warning. *** There are now two types of guardians: greedy and sharing. If you call (make-guardian #t) or just (make-guardian), you'll get a greedy guardian, and for (make-guardian #f) a sharing guardian. Greedy guardians are the default because they are more "defensive". You can only greedily guard an object once. If you guard an object more than once, once in a greedy guardian and the rest of times in sharing guardians, then it is guaranteed that the object won't be returned from sharing guardians as long as it is greedily guarded and/or alive. Guardians returned by calls to `make-guardian' can now take one more optional parameter, which says whether to throw an error in case an attempt is made to greedily guard an object that is already greedily guarded. The default is true, i.e. throw an error. If the parameter is false, the guardian invocation returns #t if guarding was successful and #f if it wasn't. Also, since greedy guarding is, in effect, a side-effecting operation on objects, a new function is introduced: `destroy-guardian!'. Invoking this function on a guardian renders it unoperative and, if the guardian is greedy, clears the "greedily guarded" property of the objects that were guarded by it, thus undoing the side effect. Note that all this hair is hardly very important, since guardian objects are usually permanent. ** Continuations created by call-with-current-continuation now accept any number of arguments, as required by R5RS. ** New function `issue-deprecation-warning' This function is used to display the deprecation messages that are controlled by GUILE_WARN_DEPRECATION as explained in the README. (define (id x) (issue-deprecation-warning "`id' is deprecated. Use `identity' instead.") (identity x)) guile> (id 1) ;; `id' is deprecated. Use `identity' instead. 1 guile> (id 1) 1 ** New syntax `begin-deprecated' When deprecated features are included (as determined by the configure option --enable-deprecated), `begin-deprecated' is identical to `begin'. When deprecated features are excluded, it always evaluates to `#f', ignoring the body forms. ** New function `make-object-property' This function returns a new `procedure with setter' P that can be used to attach a property to objects. When calling P as (set! (P obj) val) where `obj' is any kind of object, it attaches `val' to `obj' in such a way that it can be retrieved by calling P as (P obj) This function will replace procedure properties, symbol properties and source properties eventually. ** Module (ice-9 optargs) now uses keywords instead of `#&'. Instead of #&optional, #&key, etc you should now use #:optional, #:key, etc. Since #:optional is a keyword, you can write it as just :optional when (read-set! keywords 'prefix) is active. The old reader syntax `#&' is still supported, but deprecated. It will be removed in the next release. ** New define-module option: pure Tells the module system not to include any bindings from the root module. Example: (define-module (totally-empty-module) :pure) ** New define-module option: export NAME1 ... Export names NAME1 ... This option is required if you want to be able to export bindings from a module which doesn't import one of `define-public' or `export'. Example: (define-module (foo) :pure :use-module (ice-9 r5rs) :export (bar)) ;;; Note that we're pure R5RS below this point! (define (bar) ...) ** New function: object->string OBJ Return a Scheme string obtained by printing a given object. ** New function: port? X Returns a boolean indicating whether X is a port. Equivalent to `(or (input-port? X) (output-port? X))'. ** New function: file-port? Determines whether a given object is a port that is related to a file. ** New function: port-for-each proc Apply PROC to each port in the Guile port table in turn. The return value is unspecified. More specifically, PROC is applied exactly once to every port that exists in the system at the time PORT-FOR-EACH is invoked. Changes to the port table while PORT-FOR-EACH is running have no effect as far as PORT-FOR-EACH is concerned. ** New function: dup2 oldfd newfd A simple wrapper for the `dup2' system call. Copies the file descriptor OLDFD to descriptor number NEWFD, replacing the previous meaning of NEWFD. Both OLDFD and NEWFD must be integers. Unlike for dup->fdes or primitive-move->fdes, no attempt is made to move away ports which are using NEWFD. The return value is unspecified. ** New function: close-fdes fd A simple wrapper for the `close' system call. Close file descriptor FD, which must be an integer. Unlike close (*note close: Ports and File Descriptors.), the file descriptor will be closed even if a port is using it. The return value is unspecified. ** New function: crypt password salt Encrypts `password' using the standard unix password encryption algorithm. ** New function: chroot path Change the root directory of the running process to `path'. ** New functions: getlogin, cuserid Return the login name or the user name of the current effective user id, respectively. ** New functions: getpriority which who, setpriority which who prio Get or set the priority of the running process. ** New function: getpass prompt Read a password from the terminal, first displaying `prompt' and disabling echoing. ** New function: flock file operation Set/remove an advisory shared or exclusive lock on `file'. ** New functions: sethostname name, gethostname Set or get the hostname of the machine the current process is running on. ** New function: mkstemp! tmpl mkstemp creates a new unique file in the file system and returns a new buffered port open for reading and writing to the file. TMPL is a string specifying where the file should be created: it must end with `XXXXXX' and will be changed in place to return the name of the temporary file. ** New function: open-input-string string Return an input string port which delivers the characters from `string'. This procedure, together with `open-output-string' and `get-output-string' implements SRFI-6. ** New function: open-output-string Return an output string port which collects all data written to it. The data can then be retrieved by `get-output-string'. ** New function: get-output-string Return the contents of an output string port. ** New function: identity Return the argument. ** socket, connect, accept etc., now have support for IPv6. IPv6 addresses are represented in Scheme as integers with normal host byte ordering. ** New function: inet-pton family address Convert a printable string network address into an integer. Note that unlike the C version of this function, the result is an integer with normal host byte ordering. FAMILY can be `AF_INET' or `AF_INET6'. e.g., (inet-pton AF_INET "127.0.0.1") => 2130706433 (inet-pton AF_INET6 "::1") => 1 ** New function: inet-ntop family address Convert an integer network address into a printable string. Note that unlike the C version of this function, the input is an integer with normal host byte ordering. FAMILY can be `AF_INET' or `AF_INET6'. e.g., (inet-ntop AF_INET 2130706433) => "127.0.0.1" (inet-ntop AF_INET6 (- (expt 2 128) 1)) => ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff ** Deprecated: id Use `identity' instead. ** Deprecated: -1+ Use `1-' instead. ** Deprecated: return-it Do without it. ** Deprecated: string-character-length Use `string-length' instead. ** Deprecated: flags Use `logior' instead. ** Deprecated: close-all-ports-except. This was intended for closing ports in a child process after a fork, but it has the undesirable side effect of flushing buffers. port-for-each is more flexible. ** The (ice-9 popen) module now attempts to set up file descriptors in the child process from the current Scheme ports, instead of using the current values of file descriptors 0, 1, and 2 in the parent process. ** Removed function: builtin-weak-bindings There is no such concept as a weak binding any more. ** Removed constants: bignum-radix, scm-line-incrementors ** define-method: New syntax mandatory. The new method syntax is now mandatory: (define-method (NAME ARG-SPEC ...) BODY ...) (define-method (NAME ARG-SPEC ... . REST-ARG) BODY ...) ARG-SPEC ::= ARG-NAME | (ARG-NAME TYPE) REST-ARG ::= ARG-NAME If you have old code using the old syntax, import (oop goops old-define-method) before (oop goops) as in: (use-modules (oop goops old-define-method) (oop goops)) ** Deprecated function: builtin-variable Removed function: builtin-bindings There is no longer a distinction between builtin or other variables. Use module system operations for all variables. ** Lazy-catch handlers are no longer allowed to return. That is, a call to `throw', `error', etc is now guaranteed to not return. ** Bugfixes for (ice-9 getopt-long) This module is now tested using test-suite/tests/getopt-long.test. The following bugs have been fixed: *** Parsing for options that are specified to have `optional' args now checks if the next element is an option instead of unconditionally taking it as the option arg. *** An error is now thrown for `--opt=val' when the option description does not specify `(value #t)' or `(value optional)'. This condition used to be accepted w/o error, contrary to the documentation. *** The error message for unrecognized options is now more informative. It used to be "not a record", an artifact of the implementation. *** The error message for `--opt' terminating the arg list (no value), when `(value #t)' is specified, is now more informative. It used to be "not enough args". *** "Clumped" single-char args now preserve trailing string, use it as arg. The expansion used to be like so: ("-abc5d" "--xyz") => ("-a" "-b" "-c" "--xyz") Note that the "5d" is dropped. Now it is like so: ("-abc5d" "--xyz") => ("-a" "-b" "-c" "5d" "--xyz") This enables single-char options to have adjoining arguments as long as their constituent characters are not potential single-char options. ** (ice-9 session) procedure `arity' now works with (ice-9 optargs) `lambda*' The `lambda*' and derivative forms in (ice-9 optargs) now set a procedure property `arglist', which can be retrieved by `arity'. The result is that `arity' can give more detailed information than before: Before: guile> (use-modules (ice-9 optargs)) guile> (define* (foo #:optional a b c) a) guile> (arity foo) 0 or more arguments in `lambda*:G0'. After: guile> (arity foo) 3 optional arguments: `a', `b' and `c'. guile> (define* (bar a b #:key c d #:allow-other-keys) a) guile> (arity bar) 2 required arguments: `a' and `b', 2 keyword arguments: `c' and `d', other keywords allowed. guile> (define* (baz a b #:optional c #:rest r) a) guile> (arity baz) 2 required arguments: `a' and `b', 1 optional argument: `c', the rest in `r'. * Changes to the C interface ** Types have been renamed from scm_*_t to scm_t_*. This has been done for POSIX sake. It reserves identifiers ending with "_t". What a concept. The old names are still available with status `deprecated'. ** scm_t_bits (former scm_bits_t) is now a unsigned type. ** Deprecated features have been removed. *** Macros removed SCM_INPORTP, SCM_OUTPORTP SCM_ICHRP, SCM_ICHR, SCM_MAKICHR SCM_SETJMPBUF SCM_NSTRINGP SCM_NRWSTRINGP SCM_NVECTORP SCM_DOUBLE_CELLP *** C Functions removed scm_sysmissing scm_tag scm_tc16_flo scm_tc_flo scm_fseek - replaced by scm_seek. gc-thunk - replaced by after-gc-hook. gh_int2scmb - replaced by gh_bool2scm. scm_tc_dblr - replaced by scm_tc16_real. scm_tc_dblc - replaced by scm_tc16_complex. scm_list_star - replaced by scm_cons_star. ** Deprecated: scm_makfromstr Use scm_mem2string instead. ** Deprecated: scm_make_shared_substring Explicit shared substrings will disappear from Guile. Instead, "normal" strings will be implemented using sharing internally, combined with a copy-on-write strategy. ** Deprecated: scm_read_only_string_p The concept of read-only strings will disappear in next release of Guile. ** Deprecated: scm_sloppy_memq, scm_sloppy_memv, scm_sloppy_member Instead, use scm_c_memq or scm_memq, scm_memv, scm_member. ** New functions: scm_call_0, scm_call_1, scm_call_2, scm_call_3 Call a procedure with the indicated number of arguments. See "Fly Evaluation" in the manual. ** New functions: scm_apply_0, scm_apply_1, scm_apply_2, scm_apply_3 Call a procedure with the indicated number of arguments and a list of further arguments. See "Fly Evaluation" in the manual. ** New functions: scm_list_1, scm_list_2, scm_list_3, scm_list_4, scm_list_5 Create a list of the given number of elements. See "List Constructors" in the manual. ** Renamed function: scm_listify has been replaced by scm_list_n. ** Deprecated macros: SCM_LIST0, SCM_LIST1, SCM_LIST2, SCM_LIST3, SCM_LIST4, SCM_LIST5, SCM_LIST6, SCM_LIST7, SCM_LIST8, SCM_LIST9. Use functions scm_list_N instead. ** New function: scm_c_read (SCM port, void *buffer, scm_sizet size) Used by an application to read arbitrary number of bytes from a port. Same semantics as libc read, except that scm_c_read only returns less than SIZE bytes if at end-of-file. Warning: Doesn't update port line and column counts! ** New function: scm_c_write (SCM port, const void *ptr, scm_sizet size) Used by an application to write arbitrary number of bytes to an SCM port. Similar semantics as libc write. However, unlike libc write, scm_c_write writes the requested number of bytes and has no return value. Warning: Doesn't update port line and column counts! ** New function: scm_init_guile () In contrast to scm_boot_guile, scm_init_guile will return normally after initializing Guile. It is not available on all systems, tho. ** New functions: scm_str2symbol, scm_mem2symbol The function scm_str2symbol takes a const char* pointing to a zero-terminated field of characters and creates a scheme symbol object from that C string. The function scm_mem2symbol takes a const char* and a number of characters and creates a symbol from the characters in that memory area. ** New functions: scm_primitive_make_property scm_primitive_property_ref scm_primitive_property_set_x scm_primitive_property_del_x These functions implement a new way to deal with object properties. See libguile/properties.c for their documentation. ** New function: scm_done_free (long size) This function is the inverse of scm_done_malloc. Use it to report the amount of smob memory you free. The previous method, which involved calling scm_done_malloc with negative argument, was somewhat unintuitive (and is still available, of course). ** New function: scm_c_memq (SCM obj, SCM list) This function provides a fast C level alternative for scm_memq for the case that the list parameter is known to be a proper list. The function is a replacement for scm_sloppy_memq, but is stricter in its requirements on its list input parameter, since for anything else but a proper list the function's behaviour is undefined - it may even crash or loop endlessly. Further, for the case that the object is not found in the list, scm_c_memq returns #f which is similar to scm_memq, but different from scm_sloppy_memq's behaviour. ** New functions: scm_remember_upto_here_1, scm_remember_upto_here_2, scm_remember_upto_here These functions replace the function scm_remember. ** Deprecated function: scm_remember Use one of the new functions scm_remember_upto_here_1, scm_remember_upto_here_2 or scm_remember_upto_here instead. ** New function: scm_allocate_string This function replaces the function scm_makstr. ** Deprecated function: scm_makstr Use the new function scm_allocate_string instead. ** New global variable scm_gc_running_p introduced. Use this variable to find out if garbage collection is being executed. Up to now applications have used scm_gc_heap_lock to test if garbage collection was running, which also works because of the fact that up to know only the garbage collector has set this variable. But, this is an implementation detail that may change. Further, scm_gc_heap_lock is not set throughout gc, thus the use of this variable is (and has been) not fully safe anyway. ** New macros: SCM_BITVECTOR_MAX_LENGTH, SCM_UVECTOR_MAX_LENGTH Use these instead of SCM_LENGTH_MAX. ** New macros: SCM_CONTINUATION_LENGTH, SCM_CCLO_LENGTH, SCM_STACK_LENGTH, SCM_STRING_LENGTH, SCM_SYMBOL_LENGTH, SCM_UVECTOR_LENGTH, SCM_BITVECTOR_LENGTH, SCM_VECTOR_LENGTH. Use these instead of SCM_LENGTH. ** New macros: SCM_SET_CONTINUATION_LENGTH, SCM_SET_STRING_LENGTH, SCM_SET_SYMBOL_LENGTH, SCM_SET_VECTOR_LENGTH, SCM_SET_UVECTOR_LENGTH, SCM_SET_BITVECTOR_LENGTH Use these instead of SCM_SETLENGTH ** New macros: SCM_STRING_CHARS, SCM_SYMBOL_CHARS, SCM_CCLO_BASE, SCM_VECTOR_BASE, SCM_UVECTOR_BASE, SCM_BITVECTOR_BASE, SCM_COMPLEX_MEM, SCM_ARRAY_MEM Use these instead of SCM_CHARS, SCM_UCHARS, SCM_ROCHARS, SCM_ROUCHARS or SCM_VELTS. ** New macros: SCM_SET_BIGNUM_BASE, SCM_SET_STRING_CHARS, SCM_SET_SYMBOL_CHARS, SCM_SET_UVECTOR_BASE, SCM_SET_BITVECTOR_BASE, SCM_SET_VECTOR_BASE Use these instead of SCM_SETCHARS. ** New macro: SCM_BITVECTOR_P ** New macro: SCM_STRING_COERCE_0TERMINATION_X Use instead of SCM_COERCE_SUBSTR. ** New macros: SCM_DIR_OPEN_P, SCM_DIR_FLAG_OPEN For directory objects, use these instead of SCM_OPDIRP and SCM_OPN. ** Deprecated macros: SCM_OUTOFRANGE, SCM_NALLOC, SCM_HUP_SIGNAL, SCM_INT_SIGNAL, SCM_FPE_SIGNAL, SCM_BUS_SIGNAL, SCM_SEGV_SIGNAL, SCM_ALRM_SIGNAL, SCM_GC_SIGNAL, SCM_TICK_SIGNAL, SCM_SIG_ORD, SCM_ORD_SIG, SCM_NUM_SIGS, SCM_SYMBOL_SLOTS, SCM_SLOTS, SCM_SLOPPY_STRINGP, SCM_VALIDATE_STRINGORSUBSTR, SCM_FREEP, SCM_NFREEP, SCM_CHARS, SCM_UCHARS, SCM_VALIDATE_ROSTRING, SCM_VALIDATE_ROSTRING_COPY, SCM_VALIDATE_NULLORROSTRING_COPY, SCM_ROLENGTH, SCM_LENGTH, SCM_HUGE_LENGTH, SCM_SUBSTRP, SCM_SUBSTR_STR, SCM_SUBSTR_OFFSET, SCM_COERCE_SUBSTR, SCM_ROSTRINGP, SCM_RWSTRINGP, SCM_VALIDATE_RWSTRING, SCM_ROCHARS, SCM_ROUCHARS, SCM_SETLENGTH, SCM_SETCHARS, SCM_LENGTH_MAX, SCM_GC8MARKP, SCM_SETGC8MARK, SCM_CLRGC8MARK, SCM_GCTYP16, SCM_GCCDR, SCM_SUBR_DOC, SCM_OPDIRP, SCM_VALIDATE_OPDIR, SCM_WTA, RETURN_SCM_WTA, SCM_CONST_LONG, SCM_WNA, SCM_FUNC_NAME, SCM_VALIDATE_NUMBER_COPY, SCM_VALIDATE_NUMBER_DEF_COPY, SCM_SLOPPY_CONSP, SCM_SLOPPY_NCONSP, SCM_SETAND_CDR, SCM_SETOR_CDR, SCM_SETAND_CAR, SCM_SETOR_CAR Use SCM_ASSERT_RANGE or SCM_VALIDATE_XXX_RANGE instead of SCM_OUTOFRANGE. Use scm_memory_error instead of SCM_NALLOC. Use SCM_STRINGP instead of SCM_SLOPPY_STRINGP. Use SCM_VALIDATE_STRING instead of SCM_VALIDATE_STRINGORSUBSTR. Use SCM_FREE_CELL_P instead of SCM_FREEP/SCM_NFREEP Use a type specific accessor macro instead of SCM_CHARS/SCM_UCHARS. Use a type specific accessor instead of SCM(_|_RO|_HUGE_)LENGTH. Use SCM_VALIDATE_(SYMBOL|STRING) instead of SCM_VALIDATE_ROSTRING. Use SCM_STRING_COERCE_0TERMINATION_X instead of SCM_COERCE_SUBSTR. Use SCM_STRINGP or SCM_SYMBOLP instead of SCM_ROSTRINGP. Use SCM_STRINGP instead of SCM_RWSTRINGP. Use SCM_VALIDATE_STRING instead of SCM_VALIDATE_RWSTRING. Use SCM_STRING_CHARS instead of SCM_ROCHARS. Use SCM_STRING_UCHARS instead of SCM_ROUCHARS. Use a type specific setter macro instead of SCM_SETLENGTH. Use a type specific setter macro instead of SCM_SETCHARS. Use a type specific length macro instead of SCM_LENGTH_MAX. Use SCM_GCMARKP instead of SCM_GC8MARKP. Use SCM_SETGCMARK instead of SCM_SETGC8MARK. Use SCM_CLRGCMARK instead of SCM_CLRGC8MARK. Use SCM_TYP16 instead of SCM_GCTYP16. Use SCM_CDR instead of SCM_GCCDR. Use SCM_DIR_OPEN_P instead of SCM_OPDIRP. Use SCM_MISC_ERROR or SCM_WRONG_TYPE_ARG instead of SCM_WTA. Use SCM_MISC_ERROR or SCM_WRONG_TYPE_ARG instead of RETURN_SCM_WTA. Use SCM_VCELL_INIT instead of SCM_CONST_LONG. Use SCM_WRONG_NUM_ARGS instead of SCM_WNA. Use SCM_CONSP instead of SCM_SLOPPY_CONSP. Use !SCM_CONSP instead of SCM_SLOPPY_NCONSP. ** Removed function: scm_struct_init ** Removed variable: scm_symhash_dim ** Renamed function: scm_make_cont has been replaced by scm_make_continuation, which has a different interface. ** Deprecated function: scm_call_catching_errors Use scm_catch or scm_lazy_catch from throw.[ch] instead. ** Deprecated function: scm_strhash Use scm_string_hash instead. ** Deprecated function: scm_vector_set_length_x Instead, create a fresh vector of the desired size and copy the contents. ** scm_gensym has changed prototype scm_gensym now only takes one argument. ** Deprecated type tags: scm_tc7_ssymbol, scm_tc7_msymbol, scm_tcs_symbols, scm_tc7_lvector There is now only a single symbol type scm_tc7_symbol. The tag scm_tc7_lvector was not used anyway. ** Deprecated function: scm_make_smob_type_mfpe, scm_set_smob_mfpe. Use scm_make_smob_type and scm_set_smob_XXX instead. ** New function scm_set_smob_apply. This can be used to set an apply function to a smob type. ** Deprecated function: scm_strprint_obj Use scm_object_to_string instead. ** Deprecated function: scm_wta Use scm_wrong_type_arg, or another appropriate error signalling function instead. ** Explicit support for obarrays has been deprecated. Use `scm_str2symbol' and the generic hashtable functions instead. ** The concept of `vcells' has been deprecated. The data type `variable' is now used exclusively. `Vcells' have been a low-level concept so you are likely not affected by this change. *** Deprecated functions: scm_sym2vcell, scm_sysintern, scm_sysintern0, scm_symbol_value0, scm_intern, scm_intern0. Use scm_c_define or scm_c_lookup instead, as appropriate. *** New functions: scm_c_module_lookup, scm_c_lookup, scm_c_module_define, scm_c_define, scm_module_lookup, scm_lookup, scm_module_define, scm_define. These functions work with variables instead of with vcells. ** New functions for creating and defining `subr's and `gsubr's. The new functions more clearly distinguish between creating a subr (or gsubr) object and adding it to the current module. These new functions are available: scm_c_make_subr, scm_c_define_subr, scm_c_make_subr_with_generic, scm_c_define_subr_with_generic, scm_c_make_gsubr, scm_c_define_gsubr, scm_c_make_gsubr_with_generic, scm_c_define_gsubr_with_generic. ** Deprecated functions: scm_make_subr, scm_make_subr_opt, scm_make_subr_with_generic, scm_make_gsubr, scm_make_gsubr_with_generic. Use the new ones from above instead. ** C interface to the module system has changed. While we suggest that you avoid as many explicit module system operations from C as possible for the time being, the C interface has been made more similar to the high-level Scheme module system. *** New functions: scm_c_define_module, scm_c_use_module, scm_c_export, scm_c_resolve_module. They mostly work like their Scheme namesakes. scm_c_define_module takes a function that is called a context where the new module is current. *** Deprecated functions: scm_the_root_module, scm_make_module, scm_ensure_user_module, scm_load_scheme_module. Use the new functions instead. ** Renamed function: scm_internal_with_fluids becomes scm_c_with_fluids. scm_internal_with_fluids is available as a deprecated function. ** New function: scm_c_with_fluid. Just like scm_c_with_fluids, but takes one fluid and one value instead of lists of same. ** Deprecated typedefs: long_long, ulong_long. They are of questionable utility and they pollute the global namespace. ** Deprecated typedef: scm_sizet It is of questionable utility now that Guile requires ANSI C, and is oddly named. ** Deprecated typedefs: scm_port_rw_active, scm_port, scm_ptob_descriptor, scm_debug_info, scm_debug_frame, scm_fport, scm_option, scm_rstate, scm_rng, scm_array, scm_array_dim. Made more compliant with the naming policy by adding a _t at the end. ** Deprecated functions: scm_mkbig, scm_big2num, scm_adjbig, scm_normbig, scm_copybig, scm_2ulong2big, scm_dbl2big, scm_big2dbl With the exception of the mysterious scm_2ulong2big, they are still available under new names (scm_i_mkbig etc). These functions are not intended to be used in user code. You should avoid dealing with bignums directly, and should deal with numbers in general (which can be bignums). ** Change in behavior: scm_num2long, scm_num2ulong The scm_num2[u]long functions don't any longer accept an inexact argument. This change in behavior is motivated by concordance with R5RS: It is more common that a primitive doesn't want to accept an inexact for an exact. ** New functions: scm_short2num, scm_ushort2num, scm_int2num, scm_uint2num, scm_size2num, scm_ptrdiff2num, scm_num2short, scm_num2ushort, scm_num2int, scm_num2uint, scm_num2ptrdiff, scm_num2size. These are conversion functions between the various ANSI C integral types and Scheme numbers. NOTE: The scm_num2xxx functions don't accept an inexact argument. ** New functions: scm_float2num, scm_double2num, scm_num2float, scm_num2double. These are conversion functions between the two ANSI C float types and Scheme numbers. ** New number validation macros: SCM_NUM2{SIZE,PTRDIFF,SHORT,USHORT,INT,UINT}[_DEF] See above. ** New functions: scm_gc_protect_object, scm_gc_unprotect_object These are just nicer-named old scm_protect_object and scm_unprotect_object. ** Deprecated functions: scm_protect_object, scm_unprotect_object ** New functions: scm_gc_[un]register_root, scm_gc_[un]register_roots These functions can be used to register pointers to locations that hold SCM values. ** Deprecated function: scm_create_hook. Its sins are: misleading name, non-modularity and lack of general usefulness. Changes since Guile 1.3.4: * Changes to the distribution ** Trees from nightly snapshots and CVS now require you to run autogen.sh. We've changed the way we handle generated files in the Guile source repository. As a result, the procedure for building trees obtained from the nightly FTP snapshots or via CVS has changed: - You must have appropriate versions of autoconf, automake, and libtool installed on your system. See README for info on how to obtain these programs. - Before configuring the tree, you must first run the script `autogen.sh' at the top of the source tree. The Guile repository used to contain not only source files, written by humans, but also some generated files, like configure scripts and Makefile.in files. Even though the contents of these files could be derived mechanically from other files present, we thought it would make the tree easier to build if we checked them into CVS. However, this approach means that minor differences between developer's installed tools and habits affected the whole team. So we have removed the generated files from the repository, and added the autogen.sh script, which will reconstruct them appropriately. ** configure now has experimental options to remove support for certain features: --disable-arrays omit array and uniform array support --disable-posix omit posix interfaces --disable-networking omit networking interfaces --disable-regex omit regular expression interfaces These are likely to become separate modules some day. ** New configure option --enable-debug-freelist This enables a debugging version of SCM_NEWCELL(), and also registers an extra primitive, the setter `gc-set-debug-check-freelist!'. Configure with the --enable-debug-freelist option to enable the gc-set-debug-check-freelist! primitive, and then use: (gc-set-debug-check-freelist! #t) # turn on checking of the freelist (gc-set-debug-check-freelist! #f) # turn off checking Checking of the freelist forces a traversal of the freelist and a garbage collection before each allocation of a cell. This can slow down the interpreter dramatically, so the setter should be used to turn on this extra processing only when necessary. ** New configure option --enable-debug-malloc Include code for debugging of calls to scm_must_malloc/realloc/free. Checks that 1. objects freed by scm_must_free has been mallocated by scm_must_malloc 2. objects reallocated by scm_must_realloc has been allocated by scm_must_malloc 3. reallocated objects are reallocated with the same what string But, most importantly, it records the number of allocated objects of each kind. This is useful when searching for memory leaks. A Guile compiled with this option provides the primitive `malloc-stats' which returns an alist with pairs of kind and the number of objects of that kind. ** All includes are now referenced relative to the root directory Since some users have had problems with mixups between Guile and system headers, we have decided to always refer to Guile headers via their parent directories. This essentially creates a "private name space" for Guile headers. This means that the compiler only is given -I options for the root build and root source directory. ** Header files kw.h and genio.h have been removed. ** The module (ice-9 getopt-gnu-style) has been removed. ** New module (ice-9 documentation) Implements the interface to documentation strings associated with objects. ** New module (ice-9 time) Provides a macro `time', which displays execution time of a given form. ** New module (ice-9 history) Loading this module enables value history in the repl. * Changes to the stand-alone interpreter ** New command line option --debug Start Guile with debugging evaluator and backtraces enabled. This is useful when debugging your .guile init file or scripts. ** New help facility Usage: (help NAME) gives documentation about objects named NAME (a symbol) (help REGEXP) ditto for objects with names matching REGEXP (a string) (help 'NAME) gives documentation for NAME, even if it is not an object (help ,EXPR) gives documentation for object returned by EXPR (help (my module)) gives module commentary for `(my module)' (help) gives this text `help' searches among bindings exported from loaded modules, while `apropos' searches among bindings visible from the "current" module. Examples: (help help) (help cons) (help "output-string") ** `help' and `apropos' now prints full module names ** Dynamic linking now uses libltdl from the libtool package. The old system dependent code for doing dynamic linking has been replaced with calls to the libltdl functions which do all the hairy details for us. The major improvement is that you can now directly pass libtool library names like "libfoo.la" to `dynamic-link' and `dynamic-link' will be able to do the best shared library job you can get, via libltdl. The way dynamic libraries are found has changed and is not really portable across platforms, probably. It is therefore recommended to use absolute filenames when possible. If you pass a filename without an extension to `dynamic-link', it will try a few appropriate ones. Thus, the most platform ignorant way is to specify a name like "libfoo", without any directories and extensions. ** Guile COOP threads are now compatible with LinuxThreads Previously, COOP threading wasn't possible in applications linked with Linux POSIX threads due to their use of the stack pointer to find the thread context. This has now been fixed with a workaround which uses the pthreads to allocate the stack. ** New primitives: `pkgdata-dir', `site-dir', `library-dir' ** Positions of erring expression in scripts With version 1.3.4, the location of the erring expression in Guile scipts is no longer automatically reported. (This should have been documented before the 1.3.4 release.) You can get this information by enabling recording of positions of source expressions and running the debugging evaluator. Put this at the top of your script (or in your "site" file): (read-enable 'positions) (debug-enable 'debug) ** Backtraces in scripts It is now possible to get backtraces in scripts. Put (debug-enable 'debug 'backtrace) at the top of the script. (The first options enables the debugging evaluator. The second enables backtraces.) ** Part of module system symbol lookup now implemented in C The eval closure of most modules is now implemented in C. Since this was one of the bottlenecks for loading speed, Guile now loads code substantially faster than before. ** Attempting to get the value of an unbound variable now produces an exception with a key of 'unbound-variable instead of 'misc-error. ** The initial default output port is now unbuffered if it's using a tty device. Previously in this situation it was line-buffered. ** New hook: after-gc-hook after-gc-hook takes over the role of gc-thunk. This hook is run at the first SCM_TICK after a GC. (Thus, the code is run at the same point during evaluation as signal handlers.) Note that this hook should be used only for diagnostic and debugging purposes. It is not certain that it will continue to be well-defined when this hook is run in the future. C programmers: Note the new C level hooks scm_before_gc_c_hook, scm_before_sweep_c_hook, scm_after_gc_c_hook. ** Improvements to garbage collector Guile 1.4 has a new policy for triggering heap allocation and determining the sizes of heap segments. It fixes a number of problems in the old GC. 1. The new policy can handle two separate pools of cells (2-word/4-word) better. (The old policy would run wild, allocating more and more memory for certain programs.) 2. The old code would sometimes allocate far too much heap so that the Guile process became gigantic. The new code avoids this. 3. The old code would sometimes allocate too little so that few cells were freed at GC so that, in turn, too much time was spent in GC. 4. The old code would often trigger heap allocation several times in a row. (The new scheme predicts how large the segments needs to be in order not to need further allocation.) All in all, the new GC policy will make larger applications more efficient. The new GC scheme also is prepared for POSIX threading. Threads can allocate private pools of cells ("clusters") with just a single function call. Allocation of single cells from such a cluster can then proceed without any need of inter-thread synchronization. ** New environment variables controlling GC parameters GUILE_MAX_SEGMENT_SIZE Maximal segment size (default = 2097000) Allocation of 2-word cell heaps: GUILE_INIT_SEGMENT_SIZE_1 Size of initial heap segment in bytes (default = 360000) GUILE_MIN_YIELD_1 Minimum number of freed cells at each GC in percent of total heap size (default = 40) Allocation of 4-word cell heaps (used for real numbers and misc other objects): GUILE_INIT_SEGMENT_SIZE_2, GUILE_MIN_YIELD_2 (See entry "Way for application to customize GC parameters" under section "Changes to the scm_ interface" below.) ** Guile now implements reals using 4-word cells This speeds up computation with reals. (They were earlier allocated with `malloc'.) There is still some room for optimizations, however. ** Some further steps toward POSIX thread support have been taken *** Guile's critical sections (SCM_DEFER/ALLOW_INTS) don't have much effect any longer, and many of them will be removed in next release. *** Signals are only handled at the top of the evaluator loop, immediately after I/O, and in scm_equalp. *** The GC can allocate thread private pools of pairs. * Changes to Scheme functions and syntax ** close-input-port and close-output-port are now R5RS These procedures have been turned into primitives and have R5RS behaviour. ** New procedure: simple-format PORT MESSAGE ARG1 ... (ice-9 boot) makes `format' an alias for `simple-format' until possibly extended by the more sophisticated version in (ice-9 format) (simple-format port message . args) Write MESSAGE to DESTINATION, defaulting to `current-output-port'. MESSAGE can contain ~A (was %s) and ~S (was %S) escapes. When printed, the escapes are replaced with corresponding members of ARGS: ~A formats using `display' and ~S formats using `write'. If DESTINATION is #t, then use the `current-output-port', if DESTINATION is #f, then return a string containing the formatted text. Does not add a trailing newline." ** string-ref: the second argument is no longer optional. ** string, list->string: no longer accept strings in their arguments, only characters, for compatibility with R5RS. ** New procedure: port-closed? PORT Returns #t if PORT is closed or #f if it is open. ** Deprecated: list* The list* functionality is now provided by cons* (SRFI-1 compliant) ** New procedure: cons* ARG1 ARG2 ... ARGn Like `list', but the last arg provides the tail of the constructed list, returning (cons ARG1 (cons ARG2 (cons ... ARGn))). Requires at least one argument. If given one argument, that argument is returned as result. This function is called `list*' in some other Schemes and in Common LISP. ** Removed deprecated: serial-map, serial-array-copy!, serial-array-map! ** New procedure: object-documentation OBJECT Returns the documentation string associated with OBJECT. The procedure uses a caching mechanism so that subsequent lookups are faster. Exported by (ice-9 documentation). ** module-name now returns full names of modules Previously, only the last part of the name was returned (`session' for `(ice-9 session)'). Ex: `(ice-9 session)'. * Changes to the gh_ interface ** Deprecated: gh_int2scmb Use gh_bool2scm instead. * Changes to the scm_ interface ** Guile primitives now carry docstrings! Thanks to Greg Badros! ** Guile primitives are defined in a new way: SCM_DEFINE/SCM_DEFINE1/SCM_PROC Now Guile primitives are defined using the SCM_DEFINE/SCM_DEFINE1/SCM_PROC macros and must contain a docstring that is extracted into foo.doc using a new guile-doc-snarf script (that uses guile-doc-snarf.awk). However, a major overhaul of these macros is scheduled for the next release of guile. ** Guile primitives use a new technique for validation of arguments SCM_VALIDATE_* macros are defined to ease the redundancy and improve the readability of argument checking. ** All (nearly?) K&R prototypes for functions replaced with ANSI C equivalents. ** New macros: SCM_PACK, SCM_UNPACK Compose/decompose an SCM value. The SCM type is now treated as an abstract data type and may be defined as a long, a void* or as a struct, depending on the architecture and compile time options. This makes it easier to find several types of bugs, for example when SCM values are treated as integers without conversion. Values of the SCM type should be treated as "atomic" values. These macros are used when composing/decomposing an SCM value, either because you want to access individual bits, or because you want to treat it as an integer value. E.g., in order to set bit 7 in an SCM value x, use the expression SCM_PACK (SCM_UNPACK (x) | 0x80) ** The name property of hooks is deprecated. Thus, the use of SCM_HOOK_NAME and scm_make_hook_with_name is deprecated. You can emulate this feature by using object properties. ** Deprecated macros: SCM_INPORTP, SCM_OUTPORTP, SCM_CRDY, SCM_ICHRP, SCM_ICHR, SCM_MAKICHR, SCM_SETJMPBUF, SCM_NSTRINGP, SCM_NRWSTRINGP, SCM_NVECTORP These macros will be removed in a future release of Guile. ** The following types, functions and macros from numbers.h are deprecated: scm_dblproc, SCM_UNEGFIXABLE, SCM_FLOBUFLEN, SCM_INEXP, SCM_CPLXP, SCM_REAL, SCM_IMAG, SCM_REALPART, scm_makdbl, SCM_SINGP, SCM_NUM2DBL, SCM_NO_BIGDIG ** Port internals: the rw_random variable in the scm_port structure must be set to non-zero in any random access port. In recent Guile releases it was only set for bidirectional random-access ports. ** Port internals: the seek ptob procedure is now responsible for resetting the buffers if required. The change was made so that in the special case of reading the current position (i.e., seek p 0 SEEK_CUR) the fport and strport ptobs can avoid resetting the buffers, in particular to avoid discarding unread chars. An existing port type can be fixed by adding something like the following to the beginning of the ptob seek procedure: if (pt->rw_active == SCM_PORT_READ) scm_end_input (object); else if (pt->rw_active == SCM_PORT_WRITE) ptob->flush (object); although to actually avoid resetting the buffers and discard unread chars requires further hacking that depends on the characteristics of the ptob. ** Deprecated functions: scm_fseek, scm_tag These functions are no longer used and will be removed in a future version. ** The scm_sysmissing procedure is no longer used in libguile. Unless it turns out to be unexpectedly useful to somebody, it will be removed in a future version. ** The format of error message strings has changed The two C procedures: scm_display_error and scm_error, as well as the primitive `scm-error', now use scm_simple_format to do their work. This means that the message strings of all code must be updated to use ~A where %s was used before, and ~S where %S was used before. During the period when there still are a lot of old Guiles out there, you might want to support both old and new versions of Guile. There are basically two methods to achieve this. Both methods use autoconf. Put AC_CHECK_FUNCS(scm_simple_format) in your configure.in. Method 1: Use the string concatenation features of ANSI C's preprocessor. In C: #ifdef HAVE_SCM_SIMPLE_FORMAT #define FMT_S "~S" #else #define FMT_S "%S" #endif Then represent each of your error messages using a preprocessor macro: #define E_SPIDER_ERROR "There's a spider in your " ## FMT_S ## "!!!" In Scheme: (define fmt-s (if (defined? 'simple-format) "~S" "%S")) (define make-message string-append) (define e-spider-error (make-message "There's a spider in your " fmt-s "!!!")) Method 2: Use the oldfmt function found in doc/oldfmt.c. In C: scm_misc_error ("picnic", scm_c_oldfmt0 ("There's a spider in your ~S!!!"), ...); In Scheme: (scm-error 'misc-error "picnic" (oldfmt "There's a spider in your ~S!!!") ...) ** Deprecated: coop_mutex_init, coop_condition_variable_init Don't use the functions coop_mutex_init and coop_condition_variable_init. They will change. Use scm_mutex_init and scm_cond_init instead. ** New function: int scm_cond_timedwait (scm_cond_t *COND, scm_mutex_t *MUTEX, const struct timespec *ABSTIME) `scm_cond_timedwait' atomically unlocks MUTEX and waits on COND, as `scm_cond_wait' does, but it also bounds the duration of the wait. If COND has not been signaled before time ABSTIME, the mutex MUTEX is re-acquired and `scm_cond_timedwait' returns the error code `ETIMEDOUT'. The ABSTIME parameter specifies an absolute time, with the same origin as `time' and `gettimeofday': an ABSTIME of 0 corresponds to 00:00:00 GMT, January 1, 1970. ** New function: scm_cond_broadcast (scm_cond_t *COND) `scm_cond_broadcast' restarts all the threads that are waiting on the condition variable COND. Nothing happens if no threads are waiting on COND. ** New function: scm_key_create (scm_key_t *KEY, void (*destr_function) (void *)) `scm_key_create' allocates a new TSD key. The key is stored in the location pointed to by KEY. There is no limit on the number of keys allocated at a given time. The value initially associated with the returned key is `NULL' in all currently executing threads. The DESTR_FUNCTION argument, if not `NULL', specifies a destructor function associated with the key. When a thread terminates, DESTR_FUNCTION is called on the value associated with the key in that thread. The DESTR_FUNCTION is not called if a key is deleted with `scm_key_delete' or a value is changed with `scm_setspecific'. The order in which destructor functions are called at thread termination time is unspecified. Destructors are not yet implemented. ** New function: scm_setspecific (scm_key_t KEY, const void *POINTER) `scm_setspecific' changes the value associated with KEY in the calling thread, storing the given POINTER instead. ** New function: scm_getspecific (scm_key_t KEY) `scm_getspecific' returns the value currently associated with KEY in the calling thread. ** New function: scm_key_delete (scm_key_t KEY) `scm_key_delete' deallocates a TSD key. It does not check whether non-`NULL' values are associated with that key in the currently executing threads, nor call the destructor function associated with the key. ** New function: scm_c_hook_init (scm_c_hook_t *HOOK, void *HOOK_DATA, scm_c_hook_type_t TYPE) Initialize a C level hook HOOK with associated HOOK_DATA and type TYPE. (See scm_c_hook_run ().) ** New function: scm_c_hook_add (scm_c_hook_t *HOOK, scm_c_hook_function_t FUNC, void *FUNC_DATA, int APPENDP) Add hook function FUNC with associated FUNC_DATA to HOOK. If APPENDP is true, add it last, otherwise first. The same FUNC can be added multiple times if FUNC_DATA differ and vice versa. ** New function: scm_c_hook_remove (scm_c_hook_t *HOOK, scm_c_hook_function_t FUNC, void *FUNC_DATA) Remove hook function FUNC with associated FUNC_DATA from HOOK. A function is only removed if both FUNC and FUNC_DATA matches. ** New function: void *scm_c_hook_run (scm_c_hook_t *HOOK, void *DATA) Run hook HOOK passing DATA to the hook functions. If TYPE is SCM_C_HOOK_NORMAL, all hook functions are run. The value returned is undefined. If TYPE is SCM_C_HOOK_OR, hook functions are run until a function returns a non-NULL value. This value is returned as the result of scm_c_hook_run. If all functions return NULL, NULL is returned. If TYPE is SCM_C_HOOK_AND, hook functions are run until a function returns a NULL value, and NULL is returned. If all functions returns a non-NULL value, the last value is returned. ** New C level GC hooks Five new C level hooks has been added to the garbage collector. scm_before_gc_c_hook scm_after_gc_c_hook are run before locking and after unlocking the heap. The system is thus in a mode where evaluation can take place. (Except that scm_before_gc_c_hook must not allocate new cells.) scm_before_mark_c_hook scm_before_sweep_c_hook scm_after_sweep_c_hook are run when the heap is locked. These are intended for extension of the GC in a modular fashion. Examples are the weaks and guardians modules. ** Way for application to customize GC parameters The application can set up other default values for the GC heap allocation parameters GUILE_INIT_HEAP_SIZE_1, GUILE_MIN_YIELD_1, GUILE_INIT_HEAP_SIZE_2, GUILE_MIN_YIELD_2, GUILE_MAX_SEGMENT_SIZE, by setting scm_default_init_heap_size_1, scm_default_min_yield_1, scm_default_init_heap_size_2, scm_default_min_yield_2, scm_default_max_segment_size respectively before callong scm_boot_guile. (See entry "New environment variables ..." in section "Changes to the stand-alone interpreter" above.) ** scm_protect_object/scm_unprotect_object now nest This means that you can call scm_protect_object multiple times on an object and count on the object being protected until scm_unprotect_object has been call the same number of times. The functions also have better time complexity. Still, it is usually possible to structure the application in a way that you don't need to use these functions. For example, if you use a protected standard Guile list to keep track of live objects rather than some custom data type, objects will die a natural death when they are no longer needed. ** Deprecated type tags: scm_tc16_flo, scm_tc_flo, scm_tc_dblr, scm_tc_dblc Guile does not provide the float representation for inexact real numbers any more. Now, only doubles are used to represent inexact real numbers. Further, the tag names scm_tc_dblr and scm_tc_dblc have been changed to scm_tc16_real and scm_tc16_complex, respectively. ** Removed deprecated type scm_smobfuns ** Removed deprecated function scm_newsmob ** Warning: scm_make_smob_type_mfpe might become deprecated in a future release There is an ongoing discussion among the developers whether to deprecate `scm_make_smob_type_mfpe' or not. Please use the current standard interface (scm_make_smob_type, scm_set_smob_XXX) in new code until this issue has been settled. ** Removed deprecated type tag scm_tc16_kw ** Added type tag scm_tc16_keyword (This was introduced already in release 1.3.4 but was not documented until now.) ** gdb_print now prints "*** Guile not initialized ***" until Guile initialized * Changes to system call interfaces: ** The "select" procedure now tests port buffers for the ability to provide input or accept output. Previously only the underlying file descriptors were checked. ** New variable PIPE_BUF: the maximum number of bytes that can be atomically written to a pipe. ** If a facility is not available on the system when Guile is compiled, the corresponding primitive procedure will not be defined. Previously it would have been defined but would throw a system-error exception if called. Exception handlers which catch this case may need minor modification: an error will be thrown with key 'unbound-variable instead of 'system-error. Alternatively it's now possible to use `defined?' to check whether the facility is available. ** Procedures which depend on the timezone should now give the correct result on systems which cache the TZ environment variable, even if TZ is changed without calling tzset. * Changes to the networking interfaces: ** New functions: htons, ntohs, htonl, ntohl: for converting short and long integers between network and host format. For now, it's not particularly convenient to do this kind of thing, but consider: (define write-network-long (lambda (value port) (let ((v (make-uniform-vector 1 1 0))) (uniform-vector-set! v 0 (htonl value)) (uniform-vector-write v port)))) (define read-network-long (lambda (port) (let ((v (make-uniform-vector 1 1 0))) (uniform-vector-read! v port) (ntohl (uniform-vector-ref v 0))))) ** If inet-aton fails, it now throws an error with key 'misc-error instead of 'system-error, since errno is not relevant. ** Certain gethostbyname/gethostbyaddr failures now throw errors with specific keys instead of 'system-error. The latter is inappropriate since errno will not have been set. The keys are: 'host-not-found, 'try-again, 'no-recovery and 'no-data. ** sethostent, setnetent, setprotoent, setservent: now take an optional argument STAYOPEN, which specifies whether the database remains open after a database entry is accessed randomly (e.g., using gethostbyname for the hosts database.) The default is #f. Previously #t was always used. Changes since Guile 1.3.2: * Changes to the stand-alone interpreter ** Debugger An initial version of the Guile debugger written by Chris Hanson has been added. The debugger is still under development but is included in the distribution anyway since it is already quite useful. Type (debug) after an error to enter the debugger. Type `help' inside the debugger for a description of available commands. If you prefer to have stack frames numbered and printed in anti-chronological order and prefer up in the stack to be down on the screen as is the case in gdb, you can put (debug-enable 'backwards) in your .guile startup file. (However, this means that Guile can't use indentation to indicate stack level.) The debugger is autoloaded into Guile at the first use. ** Further enhancements to backtraces There is a new debug option `width' which controls the maximum width on the screen of printed stack frames. Fancy printing parameters ("level" and "length" as in Common LISP) are adaptively adjusted for each stack frame to give maximum information while still fitting within the bounds. If the stack frame can't be made to fit by adjusting parameters, it is simply cut off at the end. This is marked with a `$'. ** Some modules are now only loaded when the repl is started The modules (ice-9 debug), (ice-9 session), (ice-9 threads) and (ice-9 regex) are now loaded into (guile-user) only if the repl has been started. The effect is that the startup time for scripts has been reduced to 30% of what it was previously. Correctly written scripts load the modules they require at the top of the file and should not be affected by this change. ** Hooks are now represented as smobs * Changes to Scheme functions and syntax ** Readline support has changed again. The old (readline-activator) module is gone. Use (ice-9 readline) instead, which now contains all readline functionality. So the code to activate readline is now (use-modules (ice-9 readline)) (activate-readline) This should work at any time, including from the guile prompt. To avoid confusion about the terms of Guile's license, please only enable readline for your personal use; please don't make it the default for others. Here is why we make this rather odd-sounding request: Guile is normally licensed under a weakened form of the GNU General Public License, which allows you to link code with Guile without placing that code under the GPL. This exception is important to some people. However, since readline is distributed under the GNU General Public License, when you link Guile with readline, either statically or dynamically, you effectively change Guile's license to the strict GPL. Whenever you link any strictly GPL'd code into Guile, uses of Guile which are normally permitted become forbidden. This is a rather non-obvious consequence of the licensing terms. So, to make sure things remain clear, please let people choose for themselves whether to link GPL'd libraries like readline with Guile. ** regexp-substitute/global has changed slightly, but incompatibly. If you include a function in the item list, the string of the match object it receives is the same string passed to regexp-substitute/global, not some suffix of that string. Correspondingly, the match's positions are relative to the entire string, not the suffix. If the regexp can match the empty string, the way matches are chosen from the string has changed. regexp-substitute/global recognizes the same set of matches that list-matches does; see below. ** New function: list-matches REGEXP STRING [FLAGS] Return a list of match objects, one for every non-overlapping, maximal match of REGEXP in STRING. The matches appear in left-to-right order. list-matches only reports matches of the empty string if there are no other matches which begin on, end at, or include the empty match's position. If present, FLAGS is passed as the FLAGS argument to regexp-exec. ** New function: fold-matches REGEXP STRING INIT PROC [FLAGS] For each match of REGEXP in STRING, apply PROC to the match object, and the last value PROC returned, or INIT for the first call. Return the last value returned by PROC. We apply PROC to the matches as they appear from left to right. This function recognizes matches according to the same criteria as list-matches. Thus, you could define list-matches like this: (define (list-matches regexp string . flags) (reverse! (apply fold-matches regexp string '() cons flags))) If present, FLAGS is passed as the FLAGS argument to regexp-exec. ** Hooks *** New function: hook? OBJ Return #t if OBJ is a hook, otherwise #f. *** New function: make-hook-with-name NAME [ARITY] Return a hook with name NAME and arity ARITY. The default value for ARITY is 0. The only effect of NAME is that it will appear when the hook object is printed to ease debugging. *** New function: hook-empty? HOOK Return #t if HOOK doesn't contain any procedures, otherwise #f. *** New function: hook->list HOOK Return a list of the procedures that are called when run-hook is applied to HOOK. ** `map' signals an error if its argument lists are not all the same length. This is the behavior required by R5RS, so this change is really a bug fix. But it seems to affect a lot of people's code, so we're mentioning it here anyway. ** Print-state handling has been made more transparent Under certain circumstances, ports are represented as a port with an associated print state. Earlier, this pair was represented as a pair (see "Some magic has been added to the printer" below). It is now indistinguishable (almost; see `get-print-state') from a port on the user level. *** New function: port-with-print-state OUTPUT-PORT PRINT-STATE Return a new port with the associated print state PRINT-STATE. *** New function: get-print-state OUTPUT-PORT Return the print state associated with this port if it exists, otherwise return #f. *** New function: directory-stream? OBJECT Returns true iff OBJECT is a directory stream --- the sort of object returned by `opendir'. ** New function: using-readline? Return #t if readline is in use in the current repl. ** structs will be removed in 1.4 Structs will be replaced in Guile 1.4. We will merge GOOPS into Guile and use GOOPS objects as the fundamental record type. * Changes to the scm_ interface ** structs will be removed in 1.4 The entire current struct interface (struct.c, struct.h) will be replaced in Guile 1.4. We will merge GOOPS into libguile and use GOOPS objects as the fundamental record type. ** The internal representation of subr's has changed Instead of giving a hint to the subr name, the CAR field of the subr now contains an index to a subr entry in scm_subr_table. *** New variable: scm_subr_table An array of subr entries. A subr entry contains the name, properties and documentation associated with the subr. The properties and documentation slots are not yet used. ** A new scheme for "forwarding" calls to a builtin to a generic function It is now possible to extend the functionality of some Guile primitives by letting them defer a call to a GOOPS generic function on argument mismatch. This means that there is no loss of efficiency in normal evaluation. Example: (use-modules (oop goops)) ; Must be GOOPS version 0.2. (define-method + ((x ) (y )) (string-append x y)) + will still be as efficient as usual in numerical calculations, but can also be used for concatenating strings. Who will be the first one to extend Guile's numerical tower to rationals? :) [OK, there a few other things to fix before this can be made in a clean way.] *** New snarf macros for defining primitives: SCM_GPROC, SCM_GPROC1 New macro: SCM_GPROC (CNAME, SNAME, REQ, OPT, VAR, CFUNC, GENERIC) New macro: SCM_GPROC1 (CNAME, SNAME, TYPE, CFUNC, GENERIC) These do the same job as SCM_PROC and SCM_PROC1, but they also define a variable GENERIC which can be used by the dispatch macros below. [This is experimental code which may change soon.] *** New macros for forwarding control to a generic on arg type error New macro: SCM_WTA_DISPATCH_1 (GENERIC, ARG1, POS, SUBR) New macro: SCM_WTA_DISPATCH_2 (GENERIC, ARG1, ARG2, POS, SUBR) These correspond to the scm_wta function call, and have the same behaviour until the user has called the GOOPS primitive `enable-primitive-generic!'. After that, these macros will apply the generic function GENERIC to the argument(s) instead of calling scm_wta. [This is experimental code which may change soon.] *** New macros for argument testing with generic dispatch New macro: SCM_GASSERT1 (COND, GENERIC, ARG1, POS, SUBR) New macro: SCM_GASSERT2 (COND, GENERIC, ARG1, ARG2, POS, SUBR) These correspond to the SCM_ASSERT macro, but will defer control to GENERIC on error after `enable-primitive-generic!' has been called. [This is experimental code which may change soon.] ** New function: SCM scm_eval_body (SCM body, SCM env) Evaluates the body of a special form. ** The internal representation of struct's has changed Previously, four slots were allocated for the procedure(s) of entities and operators. The motivation for this representation had to do with the structure of the evaluator, the wish to support tail-recursive generic functions, and efficiency. Since the generic function dispatch mechanism has changed, there is no longer a need for such an expensive representation, and the representation has been simplified. This should not make any difference for most users. ** GOOPS support has been cleaned up. Some code has been moved from eval.c to objects.c and code in both of these compilation units has been cleaned up and better structured. *** New functions for applying generic functions New function: SCM scm_apply_generic (GENERIC, ARGS) New function: SCM scm_call_generic_0 (GENERIC) New function: SCM scm_call_generic_1 (GENERIC, ARG1) New function: SCM scm_call_generic_2 (GENERIC, ARG1, ARG2) New function: SCM scm_call_generic_3 (GENERIC, ARG1, ARG2, ARG3) ** Deprecated function: scm_make_named_hook It is now replaced by: ** New function: SCM scm_create_hook (const char *name, int arity) Creates a hook in the same way as make-hook above but also binds a variable named NAME to it. This is the typical way of creating a hook from C code. Currently, the variable is created in the "current" module. This might change when we get the new module system. [The behaviour is identical to scm_make_named_hook.] Changes since Guile 1.3: * Changes to mailing lists ** Some of the Guile mailing lists have moved to sourceware.cygnus.com. See the README file to find current addresses for all the Guile mailing lists. * Changes to the distribution ** Readline support is no longer included with Guile by default. Based on the different license terms of Guile and Readline, we concluded that Guile should not *by default* cause the linking of Readline into an application program. Readline support is now offered as a separate module, which is linked into an application only when you explicitly specify it. Although Guile is GNU software, its distribution terms add a special exception to the usual GNU General Public License (GPL). Guile's license includes a clause that allows you to link Guile with non-free programs. We add this exception so as not to put Guile at a disadvantage vis-a-vis other extensibility packages that support other languages. In contrast, the GNU Readline library is distributed under the GNU General Public License pure and simple. This means that you may not link Readline, even dynamically, into an application unless it is distributed under a free software license that is compatible the GPL. Because of this difference in distribution terms, an application that can use Guile may not be able to use Readline. Now users will be explicitly offered two independent decisions about the use of these two packages. You can activate the readline support by issuing (use-modules (readline-activator)) (activate-readline) from your ".guile" file, for example. * Changes to the stand-alone interpreter ** All builtins now print as primitives. Previously builtin procedures not belonging to the fundamental subr types printed as #>. Now, they print as #. ** Backtraces slightly more intelligible. gsubr-apply and macro transformer application frames no longer appear in backtraces. * Changes to Scheme functions and syntax ** Guile now correctly handles internal defines by rewriting them into their equivalent letrec. Previously, internal defines would incrementally add to the innermost environment, without checking whether the restrictions specified in RnRS were met. This lead to the correct behaviour when these restriction actually were met, but didn't catch all illegal uses. Such an illegal use could lead to crashes of the Guile interpreter or or other unwanted results. An example of incorrect internal defines that made Guile behave erratically: (let () (define a 1) (define (b) a) (define c (1+ (b))) (define d 3) (b)) => 2 The problem with this example is that the definition of `c' uses the value of `b' directly. This confuses the meoization machine of Guile so that the second call of `b' (this time in a larger environment that also contains bindings for `c' and `d') refers to the binding of `c' instead of `a'. You could also make Guile crash with a variation on this theme: (define (foo flag) (define a 1) (define (b flag) (if flag a 1)) (define c (1+ (b flag))) (define d 3) (b #t)) (foo #f) (foo #t) From now on, Guile will issue an `Unbound variable: b' error message for both examples. ** Hooks A hook contains a list of functions which should be called on particular occasions in an existing program. Hooks are used for customization. A window manager might have a hook before-window-map-hook. The window manager uses the function run-hooks to call all functions stored in before-window-map-hook each time a window is mapped. The user can store functions in the hook using add-hook!. In Guile, hooks are first class objects. *** New function: make-hook [N_ARGS] Return a hook for hook functions which can take N_ARGS arguments. The default value for N_ARGS is 0. (See also scm_make_named_hook below.) *** New function: add-hook! HOOK PROC [APPEND_P] Put PROC at the beginning of the list of functions stored in HOOK. If APPEND_P is supplied, and non-false, put PROC at the end instead. PROC must be able to take the number of arguments specified when the hook was created. If PROC already exists in HOOK, then remove it first. *** New function: remove-hook! HOOK PROC Remove PROC from the list of functions in HOOK. *** New function: reset-hook! HOOK Clear the list of hook functions stored in HOOK. *** New function: run-hook HOOK ARG1 ... Run all hook functions stored in HOOK with arguments ARG1 ... . The number of arguments supplied must correspond to the number given when the hook was created. ** The function `dynamic-link' now takes optional keyword arguments. The only keyword argument that is currently defined is `:global BOOL'. With it, you can control whether the shared library will be linked in global mode or not. In global mode, the symbols from the linked library can be used to resolve references from other dynamically linked libraries. In non-global mode, the linked library is essentially invisible and can only be accessed via `dynamic-func', etc. The default is now to link in global mode. Previously, the default has been non-global mode. The `#:global' keyword is only effective on platforms that support the dlopen family of functions. ** New function `provided?' - Function: provided? FEATURE Return true iff FEATURE is supported by this installation of Guile. FEATURE must be a symbol naming a feature; the global variable `*features*' is a list of available features. ** Changes to the module (ice-9 expect): *** The expect-strings macro now matches `$' in a regular expression only at a line-break or end-of-file by default. Previously it would match the end of the string accumulated so far. The old behaviour can be obtained by setting the variable `expect-strings-exec-flags' to 0. *** The expect-strings macro now uses a variable `expect-strings-exec-flags' for the regexp-exec flags. If `regexp/noteol' is included, then `$' in a regular expression will still match before a line-break or end-of-file. The default is `regexp/noteol'. *** The expect-strings macro now uses a variable `expect-strings-compile-flags' for the flags to be supplied to `make-regexp'. The default is `regexp/newline', which was previously hard-coded. *** The expect macro now supplies two arguments to a match procedure: the current accumulated string and a flag to indicate whether end-of-file has been reached. Previously only the string was supplied. If end-of-file is reached, the match procedure will be called an additional time with the same accumulated string as the previous call but with the flag set. ** New module (ice-9 format), implementing the Common Lisp `format' function. This code, and the documentation for it that appears here, was borrowed from SLIB, with minor adaptations for Guile. - Function: format DESTINATION FORMAT-STRING . ARGUMENTS An almost complete implementation of Common LISP format description according to the CL reference book `Common LISP' from Guy L. Steele, Digital Press. Backward compatible to most of the available Scheme format implementations. Returns `#t', `#f' or a string; has side effect of printing according to FORMAT-STRING. If DESTINATION is `#t', the output is to the current output port and `#t' is returned. If DESTINATION is `#f', a formatted string is returned as the result of the call. NEW: If DESTINATION is a string, DESTINATION is regarded as the format string; FORMAT-STRING is then the first argument and the output is returned as a string. If DESTINATION is a number, the output is to the current error port if available by the implementation. Otherwise DESTINATION must be an output port and `#t' is returned. FORMAT-STRING must be a string. In case of a formatting error format returns `#f' and prints a message on the current output or error port. Characters are output as if the string were output by the `display' function with the exception of those prefixed by a tilde (~). For a detailed description of the FORMAT-STRING syntax please consult a Common LISP format reference manual. For a test suite to verify this format implementation load `formatst.scm'. Please send bug reports to `lutzeb@cs.tu-berlin.de'. Note: `format' is not reentrant, i.e. only one `format'-call may be executed at a time. *** Format Specification (Format version 3.0) Please consult a Common LISP format reference manual for a detailed description of the format string syntax. For a demonstration of the implemented directives see `formatst.scm'. This implementation supports directive parameters and modifiers (`:' and `@' characters). Multiple parameters must be separated by a comma (`,'). Parameters can be numerical parameters (positive or negative), character parameters (prefixed by a quote character (`''), variable parameters (`v'), number of rest arguments parameter (`#'), empty and default parameters. Directive characters are case independent. The general form of a directive is: DIRECTIVE ::= ~{DIRECTIVE-PARAMETER,}[:][@]DIRECTIVE-CHARACTER DIRECTIVE-PARAMETER ::= [ [-|+]{0-9}+ | 'CHARACTER | v | # ] *** Implemented CL Format Control Directives Documentation syntax: Uppercase characters represent the corresponding control directive characters. Lowercase characters represent control directive parameter descriptions. `~A' Any (print as `display' does). `~@A' left pad. `~MINCOL,COLINC,MINPAD,PADCHARA' full padding. `~S' S-expression (print as `write' does). `~@S' left pad. `~MINCOL,COLINC,MINPAD,PADCHARS' full padding. `~D' Decimal. `~@D' print number sign always. `~:D' print comma separated. `~MINCOL,PADCHAR,COMMACHARD' padding. `~X' Hexadecimal. `~@X' print number sign always. `~:X' print comma separated. `~MINCOL,PADCHAR,COMMACHARX' padding. `~O' Octal. `~@O' print number sign always. `~:O' print comma separated. `~MINCOL,PADCHAR,COMMACHARO' padding. `~B' Binary. `~@B' print number sign always. `~:B' print comma separated. `~MINCOL,PADCHAR,COMMACHARB' padding. `~NR' Radix N. `~N,MINCOL,PADCHAR,COMMACHARR' padding. `~@R' print a number as a Roman numeral. `~:@R' print a number as an "old fashioned" Roman numeral. `~:R' print a number as an ordinal English number. `~:@R' print a number as a cardinal English number. `~P' Plural. `~@P' prints `y' and `ies'. `~:P' as `~P but jumps 1 argument backward.' `~:@P' as `~@P but jumps 1 argument backward.' `~C' Character. `~@C' prints a character as the reader can understand it (i.e. `#\' prefixing). `~:C' prints a character as emacs does (eg. `^C' for ASCII 03). `~F' Fixed-format floating-point (prints a flonum like MMM.NNN). `~WIDTH,DIGITS,SCALE,OVERFLOWCHAR,PADCHARF' `~@F' If the number is positive a plus sign is printed. `~E' Exponential floating-point (prints a flonum like MMM.NNN`E'EE). `~WIDTH,DIGITS,EXPONENTDIGITS,SCALE,OVERFLOWCHAR,PADCHAR,EXPONENTCHARE' `~@E' If the number is positive a plus sign is printed. `~G' General floating-point (prints a flonum either fixed or exponential). `~WIDTH,DIGITS,EXPONENTDIGITS,SCALE,OVERFLOWCHAR,PADCHAR,EXPONENTCHARG' `~@G' If the number is positive a plus sign is printed. `~$' Dollars floating-point (prints a flonum in fixed with signs separated). `~DIGITS,SCALE,WIDTH,PADCHAR$' `~@$' If the number is positive a plus sign is printed. `~:@$' A sign is always printed and appears before the padding. `~:$' The sign appears before the padding. `~%' Newline. `~N%' print N newlines. `~&' print newline if not at the beginning of the output line. `~N&' prints `~&' and then N-1 newlines. `~|' Page Separator. `~N|' print N page separators. `~~' Tilde. `~N~' print N tildes. `~' Continuation Line. `~:' newline is ignored, white space left. `~@' newline is left, white space ignored. `~T' Tabulation. `~@T' relative tabulation. `~COLNUM,COLINCT' full tabulation. `~?' Indirection (expects indirect arguments as a list). `~@?' extracts indirect arguments from format arguments. `~(STR~)' Case conversion (converts by `string-downcase'). `~:(STR~)' converts by `string-capitalize'. `~@(STR~)' converts by `string-capitalize-first'. `~:@(STR~)' converts by `string-upcase'. `~*' Argument Jumping (jumps 1 argument forward). `~N*' jumps N arguments forward. `~:*' jumps 1 argument backward. `~N:*' jumps N arguments backward. `~@*' jumps to the 0th argument. `~N@*' jumps to the Nth argument (beginning from 0) `~[STR0~;STR1~;...~;STRN~]' Conditional Expression (numerical clause conditional). `~N[' take argument from N. `~@[' true test conditional. `~:[' if-else-then conditional. `~;' clause separator. `~:;' default clause follows. `~{STR~}' Iteration (args come from the next argument (a list)). `~N{' at most N iterations. `~:{' args from next arg (a list of lists). `~@{' args from the rest of arguments. `~:@{' args from the rest args (lists). `~^' Up and out. `~N^' aborts if N = 0 `~N,M^' aborts if N = M `~N,M,K^' aborts if N <= M <= K *** Not Implemented CL Format Control Directives `~:A' print `#f' as an empty list (see below). `~:S' print `#f' as an empty list (see below). `~<~>' Justification. `~:^' (sorry I don't understand its semantics completely) *** Extended, Replaced and Additional Control Directives `~MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHD' `~MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHX' `~MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHO' `~MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHB' `~N,MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHR' COMMAWIDTH is the number of characters between two comma characters. `~I' print a R4RS complex number as `~F~@Fi' with passed parameters for `~F'. `~Y' Pretty print formatting of an argument for scheme code lists. `~K' Same as `~?.' `~!' Flushes the output if format DESTINATION is a port. `~_' Print a `#\space' character `~N_' print N `#\space' characters. `~/' Print a `#\tab' character `~N/' print N `#\tab' characters. `~NC' Takes N as an integer representation for a character. No arguments are consumed. N is converted to a character by `integer->char'. N must be a positive decimal number. `~:S' Print out readproof. Prints out internal objects represented as `#<...>' as strings `"#<...>"' so that the format output can always be processed by `read'. `~:A' Print out readproof. Prints out internal objects represented as `#<...>' as strings `"#<...>"' so that the format output can always be processed by `read'. `~Q' Prints information and a copyright notice on the format implementation. `~:Q' prints format version. `~F, ~E, ~G, ~$' may also print number strings, i.e. passing a number as a string and format it accordingly. *** Configuration Variables The format module exports some configuration variables to suit the systems and users needs. There should be no modification necessary for the configuration that comes with Guile. Format detects automatically if the running scheme system implements floating point numbers and complex numbers. format:symbol-case-conv Symbols are converted by `symbol->string' so the case type of the printed symbols is implementation dependent. `format:symbol-case-conv' is a one arg closure which is either `#f' (no conversion), `string-upcase', `string-downcase' or `string-capitalize'. (default `#f') format:iobj-case-conv As FORMAT:SYMBOL-CASE-CONV but applies for the representation of implementation internal objects. (default `#f') format:expch The character prefixing the exponent value in `~E' printing. (default `#\E') *** Compatibility With Other Format Implementations SLIB format 2.x: See `format.doc'. SLIB format 1.4: Downward compatible except for padding support and `~A', `~S', `~P', `~X' uppercase printing. SLIB format 1.4 uses C-style `printf' padding support which is completely replaced by the CL `format' padding style. MIT C-Scheme 7.1: Downward compatible except for `~', which is not documented (ignores all characters inside the format string up to a newline character). (7.1 implements `~a', `~s', ~NEWLINE, `~~', `~%', numerical and variable parameters and `:/@' modifiers in the CL sense). Elk 1.5/2.0: Downward compatible except for `~A' and `~S' which print in uppercase. (Elk implements `~a', `~s', `~~', and `~%' (no directive parameters or modifiers)). Scheme->C 01nov91: Downward compatible except for an optional destination parameter: S2C accepts a format call without a destination which returns a formatted string. This is equivalent to a #f destination in S2C. (S2C implements `~a', `~s', `~c', `~%', and `~~' (no directive parameters or modifiers)). ** Changes to string-handling functions. These functions were added to support the (ice-9 format) module, above. *** New function: string-upcase STRING *** New function: string-downcase STRING These are non-destructive versions of the existing string-upcase! and string-downcase! functions. *** New function: string-capitalize! STRING *** New function: string-capitalize STRING These functions convert the first letter of each word in the string to upper case. Thus: (string-capitalize "howdy there") => "Howdy There" As with the other functions, string-capitalize! modifies the string in place, while string-capitalize returns a modified copy of its argument. *** New function: string-ci->symbol STRING Return a symbol whose name is STRING, but having the same case as if the symbol had be read by `read'. Guile can be configured to be sensitive or insensitive to case differences in Scheme identifiers. If Guile is case-insensitive, all symbols are converted to lower case on input. The `string-ci->symbol' function returns a symbol whose name in STRING, transformed as Guile would if STRING were input. *** New function: substring-move! STRING1 START END STRING2 START Copy the substring of STRING1 from START (inclusive) to END (exclusive) to STRING2 at START. STRING1 and STRING2 may be the same string, and the source and destination areas may overlap; in all cases, the function behaves as if all the characters were copied simultanously. *** Extended functions: substring-move-left! substring-move-right! These functions now correctly copy arbitrarily overlapping substrings; they are both synonyms for substring-move!. ** New module (ice-9 getopt-long), with the function `getopt-long'. getopt-long is a function for parsing command-line arguments in a manner consistent with other GNU programs. (getopt-long ARGS GRAMMAR) Parse the arguments ARGS according to the argument list grammar GRAMMAR. ARGS should be a list of strings. Its first element should be the name of the program; subsequent elements should be the arguments that were passed to the program on the command line. The `program-arguments' procedure returns a list of this form. GRAMMAR is a list of the form: ((OPTION (PROPERTY VALUE) ...) ...) Each OPTION should be a symbol. `getopt-long' will accept a command-line option named `--OPTION'. Each option can have the following (PROPERTY VALUE) pairs: (single-char CHAR) --- Accept `-CHAR' as a single-character equivalent to `--OPTION'. This is how to specify traditional Unix-style flags. (required? BOOL) --- If BOOL is true, the option is required. getopt-long will raise an error if it is not found in ARGS. (value BOOL) --- If BOOL is #t, the option accepts a value; if it is #f, it does not; and if it is the symbol `optional', the option may appear in ARGS with or without a value. (predicate FUNC) --- If the option accepts a value (i.e. you specified `(value #t)' for this option), then getopt will apply FUNC to the value, and throw an exception if it returns #f. FUNC should be a procedure which accepts a string and returns a boolean value; you may need to use quasiquotes to get it into GRAMMAR. The (PROPERTY VALUE) pairs may occur in any order, but each property may occur only once. By default, options do not have single-character equivalents, are not required, and do not take values. In ARGS, single-character options may be combined, in the usual Unix fashion: ("-x" "-y") is equivalent to ("-xy"). If an option accepts values, then it must be the last option in the combination; the value is the next argument. So, for example, using the following grammar: ((apples (single-char #\a)) (blimps (single-char #\b) (value #t)) (catalexis (single-char #\c) (value #t))) the following argument lists would be acceptable: ("-a" "-b" "bang" "-c" "couth") ("bang" and "couth" are the values for "blimps" and "catalexis") ("-ab" "bang" "-c" "couth") (same) ("-ac" "couth" "-b" "bang") (same) ("-abc" "couth" "bang") (an error, since `-b' is not the last option in its combination) If an option's value is optional, then `getopt-long' decides whether it has a value by looking at what follows it in ARGS. If the next element is a string, and it does not appear to be an option itself, then that string is the option's value. The value of a long option can appear as the next element in ARGS, or it can follow the option name, separated by an `=' character. Thus, using the same grammar as above, the following argument lists are equivalent: ("--apples" "Braeburn" "--blimps" "Goodyear") ("--apples=Braeburn" "--blimps" "Goodyear") ("--blimps" "Goodyear" "--apples=Braeburn") If the option "--" appears in ARGS, argument parsing stops there; subsequent arguments are returned as ordinary arguments, even if they resemble options. So, in the argument list: ("--apples" "Granny Smith" "--" "--blimp" "Goodyear") `getopt-long' will recognize the `apples' option as having the value "Granny Smith", but it will not recognize the `blimp' option; it will return the strings "--blimp" and "Goodyear" as ordinary argument strings. The `getopt-long' function returns the parsed argument list as an assocation list, mapping option names --- the symbols from GRAMMAR --- onto their values, or #t if the option does not accept a value. Unused options do not appear in the alist. All arguments that are not the value of any option are returned as a list, associated with the empty list. `getopt-long' throws an exception if: - it finds an unrecognized option in ARGS - a required option is omitted - an option that requires an argument doesn't get one - an option that doesn't accept an argument does get one (this can only happen using the long option `--opt=value' syntax) - an option predicate fails So, for example: (define grammar `((lockfile-dir (required? #t) (value #t) (single-char #\k) (predicate ,file-is-directory?)) (verbose (required? #f) (single-char #\v) (value #f)) (x-includes (single-char #\x)) (rnet-server (single-char #\y) (predicate ,string?)))) (getopt-long '("my-prog" "-vk" "/tmp" "foo1" "--x-includes=/usr/include" "--rnet-server=lamprod" "--" "-fred" "foo2" "foo3") grammar) => ((() "foo1" "-fred" "foo2" "foo3") (rnet-server . "lamprod") (x-includes . "/usr/include") (lockfile-dir . "/tmp") (verbose . #t)) ** The (ice-9 getopt-gnu-style) module is obsolete; use (ice-9 getopt-long). It will be removed in a few releases. ** New syntax: lambda* ** New syntax: define* ** New syntax: define*-public ** New syntax: defmacro* ** New syntax: defmacro*-public Guile now supports optional arguments. `lambda*', `define*', `define*-public', `defmacro*' and `defmacro*-public' are identical to the non-* versions except that they use an extended type of parameter list that has the following BNF syntax (parentheses are literal, square brackets indicate grouping, and `*', `+' and `?' have the usual meaning): ext-param-list ::= ( [identifier]* [#&optional [ext-var-decl]+]? [#&key [ext-var-decl]+ [#&allow-other-keys]?]? [[#&rest identifier]|[. identifier]]? ) | [identifier] ext-var-decl ::= identifier | ( identifier expression ) The semantics are best illustrated with the following documentation and examples for `lambda*': lambda* args . body lambda extended for optional and keyword arguments lambda* creates a procedure that takes optional arguments. These are specified by putting them inside brackets at the end of the paramater list, but before any dotted rest argument. For example, (lambda* (a b #&optional c d . e) '()) creates a procedure with fixed arguments a and b, optional arguments c and d, and rest argument e. If the optional arguments are omitted in a call, the variables for them are unbound in the procedure. This can be checked with the bound? macro. lambda* can also take keyword arguments. For example, a procedure defined like this: (lambda* (#&key xyzzy larch) '()) can be called with any of the argument lists (#:xyzzy 11) (#:larch 13) (#:larch 42 #:xyzzy 19) (). Whichever arguments are given as keywords are bound to values. Optional and keyword arguments can also be given default values which they take on when they are not present in a call, by giving a two-item list in place of an optional argument, for example in: (lambda* (foo #&optional (bar 42) #&key (baz 73)) (list foo bar baz)) foo is a fixed argument, bar is an optional argument with default value 42, and baz is a keyword argument with default value 73. Default value expressions are not evaluated unless they are needed and until the procedure is called. lambda* now supports two more special parameter list keywords. lambda*-defined procedures now throw an error by default if a keyword other than one of those specified is found in the actual passed arguments. However, specifying #&allow-other-keys immediately after the kyword argument declarations restores the previous behavior of ignoring unknown keywords. lambda* also now guarantees that if the same keyword is passed more than once, the last one passed is the one that takes effect. For example, ((lambda* (#&key (heads 0) (tails 0)) (display (list heads tails))) #:heads 37 #:tails 42 #:heads 99) would result in (99 47) being displayed. #&rest is also now provided as a synonym for the dotted syntax rest argument. The argument lists (a . b) and (a #&rest b) are equivalent in all respects to lambda*. This is provided for more similarity to DSSSL, MIT-Scheme and Kawa among others, as well as for refugees from other Lisp dialects. Further documentation may be found in the optargs.scm file itself. The optional argument module also exports the macros `let-optional', `let-optional*', `let-keywords', `let-keywords*' and `bound?'. These are not documented here because they may be removed in the future, but full documentation is still available in optargs.scm. ** New syntax: and-let* Guile now supports the `and-let*' form, described in the draft SRFI-2. Syntax: (land* ( ...) ...) Each should have one of the following forms: ( ) () Each or should be an identifier. Each should be a valid expression. The should be a possibly empty sequence of expressions, like the of a lambda form. Semantics: A LAND* expression is evaluated by evaluating the or of each of the s from left to right. The value of the first or that evaluates to a false value is returned; the remaining s and s are not evaluated. The forms are evaluated iff all the s and s evaluate to true values. The s and the are evaluated in an environment binding each of the preceding ( ) clauses to the value of the . Later bindings shadow earlier bindings. Guile's and-let* macro was contributed by Michael Livshin. ** New sorting functions *** New function: sorted? SEQUENCE LESS? Returns `#t' when the sequence argument is in non-decreasing order according to LESS? (that is, there is no adjacent pair `... x y ...' for which `(less? y x)'). Returns `#f' when the sequence contains at least one out-of-order pair. It is an error if the sequence is neither a list nor a vector. *** New function: merge LIST1 LIST2 LESS? LIST1 and LIST2 are sorted lists. Returns the sorted list of all elements in LIST1 and LIST2. Assume that the elements a and b1 in LIST1 and b2 in LIST2 are "equal" in the sense that (LESS? x y) --> #f for x, y in {a, b1, b2}, and that a < b1 in LIST1. Then a < b1 < b2 in the result. (Here "<" should read "comes before".) *** New procedure: merge! LIST1 LIST2 LESS? Merges two lists, re-using the pairs of LIST1 and LIST2 to build the result. If the code is compiled, and LESS? constructs no new pairs, no pairs at all will be allocated. The first pair of the result will be either the first pair of LIST1 or the first pair of LIST2. *** New function: sort SEQUENCE LESS? Accepts either a list or a vector, and returns a new sequence which is sorted. The new sequence is the same type as the input. Always `(sorted? (sort sequence less?) less?)'. The original sequence is not altered in any way. The new sequence shares its elements with the old one; no elements are copied. *** New procedure: sort! SEQUENCE LESS Returns its sorted result in the original boxes. No new storage is allocated at all. Proper usage: (set! slist (sort! slist <)) *** New function: stable-sort SEQUENCE LESS? Similar to `sort' but stable. That is, if "equal" elements are ordered a < b in the original sequence, they will have the same order in the result. *** New function: stable-sort! SEQUENCE LESS? Similar to `sort!' but stable. Uses temporary storage when sorting vectors. *** New functions: sort-list, sort-list! Added for compatibility with scsh. ** New built-in random number support *** New function: random N [STATE] Accepts a positive integer or real N and returns a number of the same type between zero (inclusive) and N (exclusive). The values returned have a uniform distribution. The optional argument STATE must be of the type produced by `copy-random-state' or `seed->random-state'. It defaults to the value of the variable `*random-state*'. This object is used to maintain the state of the pseudo-random-number generator and is altered as a side effect of the `random' operation. *** New variable: *random-state* Holds a data structure that encodes the internal state of the random-number generator that `random' uses by default. The nature of this data structure is implementation-dependent. It may be printed out and successfully read back in, but may or may not function correctly as a random-number state object in another implementation. *** New function: copy-random-state [STATE] Returns a new object of type suitable for use as the value of the variable `*random-state*' and as a second argument to `random'. If argument STATE is given, a copy of it is returned. Otherwise a copy of `*random-state*' is returned. *** New function: seed->random-state SEED Returns a new object of type suitable for use as the value of the variable `*random-state*' and as a second argument to `random'. SEED is a string or a number. A new state is generated and initialized using SEED. *** New function: random:uniform [STATE] Returns an uniformly distributed inexact real random number in the range between 0 and 1. *** New procedure: random:solid-sphere! VECT [STATE] Fills VECT with inexact real random numbers the sum of whose squares is less than 1.0. Thinking of VECT as coordinates in space of dimension N = `(vector-length VECT)', the coordinates are uniformly distributed within the unit N-shere. The sum of the squares of the numbers is returned. VECT can be either a vector or a uniform vector of doubles. *** New procedure: random:hollow-sphere! VECT [STATE] Fills VECT with inexact real random numbers the sum of whose squares is equal to 1.0. Thinking of VECT as coordinates in space of dimension n = `(vector-length VECT)', the coordinates are uniformly distributed over the surface of the unit n-shere. VECT can be either a vector or a uniform vector of doubles. *** New function: random:normal [STATE] Returns an inexact real in a normal distribution with mean 0 and standard deviation 1. For a normal distribution with mean M and standard deviation D use `(+ M (* D (random:normal)))'. *** New procedure: random:normal-vector! VECT [STATE] Fills VECT with inexact real random numbers which are independent and standard normally distributed (i.e., with mean 0 and variance 1). VECT can be either a vector or a uniform vector of doubles. *** New function: random:exp STATE Returns an inexact real in an exponential distribution with mean 1. For an exponential distribution with mean U use (* U (random:exp)). ** The range of logand, logior, logxor, logtest, and logbit? have changed. These functions now operate on numbers in the range of a C unsigned long. These functions used to operate on numbers in the range of a C signed long; however, this seems inappropriate, because Guile integers don't overflow. ** New function: make-guardian This is an implementation of guardians as described in R. Kent Dybvig, Carl Bruggeman, and David Eby (1993) "Guardians in a Generation-Based Garbage Collector" ACM SIGPLAN Conference on Programming Language Design and Implementation, June 1993 ftp://ftp.cs.indiana.edu/pub/scheme-repository/doc/pubs/guardians.ps.gz ** New functions: delq1!, delv1!, delete1! These procedures behave similar to delq! and friends but delete only one object if at all. ** New function: unread-string STRING PORT Unread STRING to PORT, that is, push it back onto the port so that next read operation will work on the pushed back characters. ** unread-char can now be called multiple times If unread-char is called multiple times, the unread characters will be read again in last-in first-out order. ** the procedures uniform-array-read! and uniform-array-write! now work on any kind of port, not just ports which are open on a file. ** Now 'l' in a port mode requests line buffering. ** The procedure truncate-file now works on string ports as well as file ports. If the size argument is omitted, the current file position is used. ** new procedure: seek PORT/FDES OFFSET WHENCE The arguments are the same as for the old fseek procedure, but it works on string ports as well as random-access file ports. ** the fseek procedure now works on string ports, since it has been redefined using seek. ** the setvbuf procedure now uses a default size if mode is _IOFBF and size is not supplied. ** the newline procedure no longer flushes the port if it's not line-buffered: previously it did if it was the current output port. ** open-pipe and close-pipe are no longer primitive procedures, but an emulation can be obtained using `(use-modules (ice-9 popen))'. ** the freopen procedure has been removed. ** new procedure: drain-input PORT Drains PORT's read buffers (including any pushed-back characters) and returns the contents as a single string. ** New function: map-in-order PROC LIST1 LIST2 ... Version of `map' which guarantees that the procedure is applied to the lists in serial order. ** Renamed `serial-array-copy!' and `serial-array-map!' to `array-copy-in-order!' and `array-map-in-order!'. The old names are now obsolete and will go away in release 1.5. ** New syntax: collect BODY1 ... Version of `begin' which returns a list of the results of the body forms instead of the result of the last body form. In contrast to `begin', `collect' allows an empty body. ** New functions: read-history FILENAME, write-history FILENAME Read/write command line history from/to file. Returns #t on success and #f if an error occured. ** `ls' and `lls' in module (ice-9 ls) now handle no arguments. These procedures return a list of definitions available in the specified argument, a relative module reference. In the case of no argument, `(current-module)' is now consulted for definitions to return, instead of simply returning #f, the former behavior. ** The #/ syntax for lists is no longer supported. Earlier versions of Scheme accepted this syntax, but printed a warning. ** Guile no longer consults the SCHEME_LOAD_PATH environment variable. Instead, you should set GUILE_LOAD_PATH to tell Guile where to find modules. * Changes to the gh_ interface ** gh_scm2doubles Now takes a second argument which is the result array. If this pointer is NULL, a new array is malloced (the old behaviour). ** gh_chars2byvect, gh_shorts2svect, gh_floats2fvect, gh_scm2chars, gh_scm2shorts, gh_scm2longs, gh_scm2floats New functions. * Changes to the scm_ interface ** Function: scm_make_named_hook (char* name, int n_args) Creates a hook in the same way as make-hook above but also binds a variable named NAME to it. This is the typical way of creating a hook from C code. Currently, the variable is created in the "current" module. This might change when we get the new module system. ** The smob interface The interface for creating smobs has changed. For documentation, see data-rep.info (made from guile-core/doc/data-rep.texi). *** Deprecated function: SCM scm_newsmob (scm_smobfuns *) >>> This function will be removed in 1.3.4. <<< It is replaced by: *** Function: SCM scm_make_smob_type (const char *name, scm_sizet size) This function adds a new smob type, named NAME, with instance size SIZE to the system. The return value is a tag that is used in creating instances of the type. If SIZE is 0, then no memory will be allocated when instances of the smob are created, and nothing will be freed by the default free function. *** Function: void scm_set_smob_mark (long tc, SCM (*mark) (SCM)) This function sets the smob marking procedure for the smob type specified by the tag TC. TC is the tag returned by `scm_make_smob_type'. *** Function: void scm_set_smob_free (long tc, SCM (*mark) (SCM)) This function sets the smob freeing procedure for the smob type specified by the tag TC. TC is the tag returned by `scm_make_smob_type'. *** Function: void scm_set_smob_print (tc, print) - Function: void scm_set_smob_print (long tc, scm_sizet (*print) (SCM, SCM, scm_print_state *)) This function sets the smob printing procedure for the smob type specified by the tag TC. TC is the tag returned by `scm_make_smob_type'. *** Function: void scm_set_smob_equalp (long tc, SCM (*equalp) (SCM, SCM)) This function sets the smob equality-testing predicate for the smob type specified by the tag TC. TC is the tag returned by `scm_make_smob_type'. *** Macro: void SCM_NEWSMOB (SCM var, long tc, void *data) Make VALUE contain a smob instance of the type with type code TC and smob data DATA. VALUE must be previously declared as C type `SCM'. *** Macro: fn_returns SCM_RETURN_NEWSMOB (long tc, void *data) This macro expands to a block of code that creates a smob instance of the type with type code TC and smob data DATA, and returns that `SCM' value. It should be the last piece of code in a block. ** The interfaces for using I/O ports and implementing port types (ptobs) have changed significantly. The new interface is based on shared access to buffers and a new set of ptob procedures. *** scm_newptob has been removed It is replaced by: *** Function: SCM scm_make_port_type (type_name, fill_buffer, write_flush) - Function: SCM scm_make_port_type (char *type_name, int (*fill_buffer) (SCM port), void (*write_flush) (SCM port)); Similarly to the new smob interface, there is a set of function setters by which the user can customize the behaviour of his port type. See ports.h (scm_set_port_XXX). ** scm_strport_to_string: New function: creates a new string from a string port's buffer. ** Plug in interface for random number generators The variable `scm_the_rng' in random.c contains a value and three function pointers which together define the current random number generator being used by the Scheme level interface and the random number library functions. The user is free to replace the default generator with the generator of his own choice. *** Variable: size_t scm_the_rng.rstate_size The size of the random state type used by the current RNG measured in chars. *** Function: unsigned long scm_the_rng.random_bits (scm_rstate *STATE) Given the random STATE, return 32 random bits. *** Function: void scm_the_rng.init_rstate (scm_rstate *STATE, chars *S, int N) Seed random state STATE using string S of length N. *** Function: scm_rstate *scm_the_rng.copy_rstate (scm_rstate *STATE) Given random state STATE, return a malloced copy. ** Default RNG The default RNG is the MWC (Multiply With Carry) random number generator described by George Marsaglia at the Department of Statistics and Supercomputer Computations Research Institute, The Florida State University (http://stat.fsu.edu/~geo). It uses 64 bits, has a period of 4578426017172946943 (4.6e18), and passes all tests in the DIEHARD test suite (http://stat.fsu.edu/~geo/diehard.html). The generation of 32 bits costs one multiply and one add on platforms which either supports long longs (gcc does this on most systems) or have 64 bit longs. The cost is four multiply on other systems but this can be optimized by writing scm_i_uniform32 in assembler. These functions are provided through the scm_the_rng interface for use by libguile and the application. *** Function: unsigned long scm_i_uniform32 (scm_i_rstate *STATE) Given the random STATE, return 32 random bits. Don't use this function directly. Instead go through the plugin interface (see "Plug in interface" above). *** Function: void scm_i_init_rstate (scm_i_rstate *STATE, char *SEED, int N) Initialize STATE using SEED of length N. *** Function: scm_i_rstate *scm_i_copy_rstate (scm_i_rstate *STATE) Return a malloc:ed copy of STATE. This function can easily be re-used in the interfaces to other RNGs. ** Random number library functions These functions use the current RNG through the scm_the_rng interface. It might be a good idea to use these functions from your C code so that only one random generator is used by all code in your program. The default random state is stored in: *** Variable: SCM scm_var_random_state Contains the vcell of the Scheme variable "*random-state*" which is used as default state by all random number functions in the Scheme level interface. Example: double x = scm_c_uniform01 (SCM_RSTATE (SCM_CDR (scm_var_random_state))); *** Function: scm_rstate *scm_c_default_rstate (void) This is a convenience function which returns the value of scm_var_random_state. An error message is generated if this value isn't a random state. *** Function: scm_rstate *scm_c_make_rstate (char *SEED, int LENGTH) Make a new random state from the string SEED of length LENGTH. It is generally not a good idea to use multiple random states in a program. While subsequent random numbers generated from one random state are guaranteed to be reasonably independent, there is no such guarantee for numbers generated from different random states. *** Macro: unsigned long scm_c_uniform32 (scm_rstate *STATE) Return 32 random bits. *** Function: double scm_c_uniform01 (scm_rstate *STATE) Return a sample from the uniform(0,1) distribution. *** Function: double scm_c_normal01 (scm_rstate *STATE) Return a sample from the normal(0,1) distribution. *** Function: double scm_c_exp1 (scm_rstate *STATE) Return a sample from the exp(1) distribution. *** Function: unsigned long scm_c_random (scm_rstate *STATE, unsigned long M) Return a sample from the discrete uniform(0,M) distribution. *** Function: SCM scm_c_random_bignum (scm_rstate *STATE, SCM M) Return a sample from the discrete uniform(0,M) distribution. M must be a bignum object. The returned value may be an INUM. Changes in Guile 1.3 (released Monday, October 19, 1998): * Changes to the distribution ** We renamed the SCHEME_LOAD_PATH environment variable to GUILE_LOAD_PATH. To avoid conflicts, programs should name environment variables after themselves, except when there's a common practice establishing some other convention. For now, Guile supports both GUILE_LOAD_PATH and SCHEME_LOAD_PATH, giving the former precedence, and printing a warning message if the latter is set. Guile 1.4 will not recognize SCHEME_LOAD_PATH at all. ** The header files related to multi-byte characters have been removed. They were: libguile/extchrs.h and libguile/mbstrings.h. Any C code which referred to these explicitly will probably need to be rewritten, since the support for the variant string types has been removed; see below. ** The header files append.h and sequences.h have been removed. These files implemented non-R4RS operations which would encourage non-portable programming style and less easy-to-read code. * Changes to the stand-alone interpreter ** New procedures have been added to implement a "batch mode": *** Function: batch-mode? Returns a boolean indicating whether the interpreter is in batch mode. *** Function: set-batch-mode?! ARG If ARG is true, switches the interpreter to batch mode. The `#f' case has not been implemented. ** Guile now provides full command-line editing, when run interactively. To use this feature, you must have the readline library installed. The Guile build process will notice it, and automatically include support for it. The readline library is available via anonymous FTP from any GNU mirror site; the canonical location is "ftp://prep.ai.mit.edu/pub/gnu". ** the-last-stack is now a fluid. * Changes to the procedure for linking libguile with your programs ** You can now use the `guile-config' utility to build programs that use Guile. Guile now includes a command-line utility called `guile-config', which can provide information about how to compile and link programs that use Guile. *** `guile-config compile' prints any C compiler flags needed to use Guile. You should include this command's output on the command line you use to compile C or C++ code that #includes the Guile header files. It's usually just a `-I' flag to help the compiler find the Guile headers. *** `guile-config link' prints any linker flags necessary to link with Guile. This command writes to its standard output a list of flags which you must pass to the linker to link your code against the Guile library. The flags include '-lguile' itself, any other libraries the Guile library depends upon, and any `-L' flags needed to help the linker find those libraries. For example, here is a Makefile rule that builds a program named 'foo' from the object files ${FOO_OBJECTS}, and links them against Guile: foo: ${FOO_OBJECTS} ${CC} ${CFLAGS} ${FOO_OBJECTS} `guile-config link` -o foo Previous Guile releases recommended that you use autoconf to detect which of a predefined set of libraries were present on your system. It is more robust to use `guile-config', since it records exactly which libraries the installed Guile library requires. This was originally called `build-guile', but was renamed to `guile-config' before Guile 1.3 was released, to be consistent with the analogous script for the GTK+ GUI toolkit, which is called `gtk-config'. ** Use the GUILE_FLAGS macro in your configure.in file to find Guile. If you are using the GNU autoconf package to configure your program, you can use the GUILE_FLAGS autoconf macro to call `guile-config' (described above) and gather the necessary values for use in your Makefiles. The GUILE_FLAGS macro expands to configure script code which runs the `guile-config' script, to find out where Guile's header files and libraries are installed. It sets two variables, marked for substitution, as by AC_SUBST. GUILE_CFLAGS --- flags to pass to a C or C++ compiler to build code that uses Guile header files. This is almost always just a -I flag. GUILE_LDFLAGS --- flags to pass to the linker to link a program against Guile. This includes `-lguile' for the Guile library itself, any libraries that Guile itself requires (like -lqthreads), and so on. It may also include a -L flag to tell the compiler where to find the libraries. GUILE_FLAGS is defined in the file guile.m4, in the top-level directory of the Guile distribution. You can copy it into your package's aclocal.m4 file, and then use it in your configure.in file. If you are using the `aclocal' program, distributed with GNU automake, to maintain your aclocal.m4 file, the Guile installation process installs guile.m4 where aclocal will find it. All you need to do is use GUILE_FLAGS in your configure.in file, and then run `aclocal'; this will copy the definition of GUILE_FLAGS into your aclocal.m4 file. * Changes to Scheme functions and syntax ** Multi-byte strings have been removed, as have multi-byte and wide ports. We felt that these were the wrong approach to internationalization support. ** New function: readline [PROMPT] Read a line from the terminal, and allow the user to edit it, prompting with PROMPT. READLINE provides a large set of Emacs-like editing commands, lets the user recall previously typed lines, and works on almost every kind of terminal, including dumb terminals. READLINE assumes that the cursor is at the beginning of the line when it is invoked. Thus, you can't print a prompt yourself, and then call READLINE; you need to package up your prompt as a string, pass it to the function, and let READLINE print the prompt itself. This is because READLINE needs to know the prompt's screen width. For Guile to provide this function, you must have the readline library, version 2.1 or later, installed on your system. Readline is available via anonymous FTP from prep.ai.mit.edu in pub/gnu, or from any GNU mirror site. See also ADD-HISTORY function. ** New function: add-history STRING Add STRING as the most recent line in the history used by the READLINE command. READLINE does not add lines to the history itself; you must call ADD-HISTORY to make previous input available to the user. ** The behavior of the read-line function has changed. This function now uses standard C library functions to read the line, for speed. This means that it doesn not respect the value of scm-line-incrementors; it assumes that lines are delimited with #\newline. (Note that this is read-line, the function that reads a line of text from a port, not readline, the function that reads a line from a terminal, providing full editing capabilities.) ** New module (ice-9 getopt-gnu-style): Parse command-line arguments. This module provides some simple argument parsing. It exports one function: Function: getopt-gnu-style ARG-LS Parse a list of program arguments into an alist of option descriptions. Each item in the list of program arguments is examined to see if it meets the syntax of a GNU long-named option. An argument like `--MUMBLE' produces an element of the form (MUMBLE . #t) in the returned alist, where MUMBLE is a keyword object with the same name as the argument. An argument like `--MUMBLE=FROB' produces an element of the form (MUMBLE . FROB), where FROB is a string. As a special case, the returned alist also contains a pair whose car is the symbol `rest'. The cdr of this pair is a list containing all the items in the argument list that are not options of the form mentioned above. The argument `--' is treated specially: all items in the argument list appearing after such an argument are not examined, and are returned in the special `rest' list. This function does not parse normal single-character switches. You will need to parse them out of the `rest' list yourself. ** The read syntax for byte vectors and short vectors has changed. Instead of #bytes(...), write #y(...). Instead of #short(...), write #h(...). This may seem nutty, but, like the other uniform vectors, byte vectors and short vectors want to have the same print and read syntax (and, more basic, want to have read syntax!). Changing the read syntax to use multiple characters after the hash sign breaks with the conventions used in R5RS and the conventions used for the other uniform vectors. It also introduces complexity in the current reader, both on the C and Scheme levels. (The Right solution is probably to change the syntax and prototypes for uniform vectors entirely.) ** The new module (ice-9 session) provides useful interactive functions. *** New procedure: (apropos REGEXP OPTION ...) Display a list of top-level variables whose names match REGEXP, and the modules they are imported from. Each OPTION should be one of the following symbols: value --- Show the value of each matching variable. shadow --- Show bindings shadowed by subsequently imported modules. full --- Same as both `shadow' and `value'. For example: guile> (apropos "trace" 'full) debug: trace # debug: untrace # the-scm-module: display-backtrace #> the-scm-module: before-backtrace-hook () the-scm-module: backtrace # the-scm-module: after-backtrace-hook () the-scm-module: has-shown-backtrace-hint? #f guile> ** There are new functions and syntax for working with macros. Guile implements macros as a special object type. Any variable whose top-level binding is a macro object acts as a macro. The macro object specifies how the expression should be transformed before evaluation. *** Macro objects now print in a reasonable way, resembling procedures. *** New function: (macro? OBJ) True iff OBJ is a macro object. *** New function: (primitive-macro? OBJ) Like (macro? OBJ), but true only if OBJ is one of the Guile primitive macro transformers, implemented in eval.c rather than Scheme code. Why do we have this function? - For symmetry with procedure? and primitive-procedure?, - to allow custom print procedures to tell whether a macro is primitive, and display it differently, and - to allow compilers and user-written evaluators to distinguish builtin special forms from user-defined ones, which could be compiled. *** New function: (macro-type OBJ) Return a value indicating what kind of macro OBJ is. Possible return values are: The symbol `syntax' --- a macro created by procedure->syntax. The symbol `macro' --- a macro created by procedure->macro. The symbol `macro!' --- a macro created by procedure->memoizing-macro. The boolean #f --- if OBJ is not a macro object. *** New function: (macro-name MACRO) Return the name of the macro object MACRO's procedure, as returned by procedure-name. *** New function: (macro-transformer MACRO) Return the transformer procedure for MACRO. *** New syntax: (use-syntax MODULE ... TRANSFORMER) Specify a new macro expander to use in the current module. Each MODULE is a module name, with the same meaning as in the `use-modules' form; each named module's exported bindings are added to the current top-level environment. TRANSFORMER is an expression evaluated in the resulting environment which must yield a procedure to use as the module's eval transformer: every expression evaluated in this module is passed to this function, and the result passed to the Guile interpreter. *** macro-eval! is removed. Use local-eval instead. ** Some magic has been added to the printer to better handle user written printing routines (like record printers, closure printers). The problem is that these user written routines must have access to the current `print-state' to be able to handle fancy things like detection of circular references. These print-states have to be passed to the builtin printing routines (display, write, etc) to properly continue the print chain. We didn't want to change all existing print code so that it explicitly passes thru a print state in addition to a port. Instead, we extented the possible values that the builtin printing routines accept as a `port'. In addition to a normal port, they now also take a pair of a normal port and a print-state. Printing will go to the port and the print-state will be used to control the detection of circular references, etc. If the builtin function does not care for a print-state, it is simply ignored. User written callbacks are now called with such a pair as their `port', but because every function now accepts this pair as a PORT argument, you don't have to worry about that. In fact, it is probably safest to not check for these pairs. However, it is sometimes necessary to continue a print chain on a different port, for example to get a intermediate string representation of the printed value, mangle that string somehow, and then to finally print the mangled string. Use the new function inherit-print-state OLD-PORT NEW-PORT for this. It constructs a new `port' that prints to NEW-PORT but inherits the print-state of OLD-PORT. ** struct-vtable-offset renamed to vtable-offset-user ** New constants: vtable-index-layout, vtable-index-vtable, vtable-index-printer ** There is now a third optional argument to make-vtable-vtable (and fourth to make-struct) when constructing new types (vtables). This argument initializes field vtable-index-printer of the vtable. ** The detection of circular references has been extended to structs. That is, a structure that -- in the process of being printed -- prints itself does not lead to infinite recursion. ** There is now some basic support for fluids. Please read "libguile/fluid.h" to find out more. It is accessible from Scheme with the following functions and macros: Function: make-fluid Create a new fluid object. Fluids are not special variables or some other extension to the semantics of Scheme, but rather ordinary Scheme objects. You can store them into variables (that are still lexically scoped, of course) or into any other place you like. Every fluid has a initial value of `#f'. Function: fluid? OBJ Test whether OBJ is a fluid. Function: fluid-ref FLUID Function: fluid-set! FLUID VAL Access/modify the fluid FLUID. Modifications are only visible within the current dynamic root (that includes threads). Function: with-fluids* FLUIDS VALUES THUNK FLUIDS is a list of fluids and VALUES a corresponding list of values for these fluids. Before THUNK gets called the values are installed in the fluids and the old values of the fluids are saved in the VALUES list. When the flow of control leaves THUNK or reenters it, the values get swapped again. You might think of this as a `safe-fluid-excursion'. Note that the VALUES list is modified by `with-fluids*'. Macro: with-fluids ((FLUID VALUE) ...) FORM ... The same as `with-fluids*' but with a different syntax. It looks just like `let', but both FLUID and VALUE are evaluated. Remember, fluids are not special variables but ordinary objects. FLUID should evaluate to a fluid. ** Changes to system call interfaces: *** close-port, close-input-port and close-output-port now return a boolean instead of an `unspecified' object. #t means that the port was successfully closed, while #f means it was already closed. It is also now possible for these procedures to raise an exception if an error occurs (some errors from write can be delayed until close.) *** the first argument to chmod, fcntl, ftell and fseek can now be a file descriptor. *** the third argument to fcntl is now optional. *** the first argument to chown can now be a file descriptor or a port. *** the argument to stat can now be a port. *** The following new procedures have been added (most use scsh interfaces): *** procedure: close PORT/FD Similar to close-port (*note close-port: Closing Ports.), but also works on file descriptors. A side effect of closing a file descriptor is that any ports using that file descriptor are moved to a different file descriptor and have their revealed counts set to zero. *** procedure: port->fdes PORT Returns the integer file descriptor underlying PORT. As a side effect the revealed count of PORT is incremented. *** procedure: fdes->ports FDES Returns a list of existing ports which have FDES as an underlying file descriptor, without changing their revealed counts. *** procedure: fdes->inport FDES Returns an existing input port which has FDES as its underlying file descriptor, if one exists, and increments its revealed count. Otherwise, returns a new input port with a revealed count of 1. *** procedure: fdes->outport FDES Returns an existing output port which has FDES as its underlying file descriptor, if one exists, and increments its revealed count. Otherwise, returns a new output port with a revealed count of 1. The next group of procedures perform a `dup2' system call, if NEWFD (an integer) is supplied, otherwise a `dup'. The file descriptor to be duplicated can be supplied as an integer or contained in a port. The type of value returned varies depending on which procedure is used. All procedures also have the side effect when performing `dup2' that any ports using NEWFD are moved to a different file descriptor and have their revealed counts set to zero. *** procedure: dup->fdes PORT/FD [NEWFD] Returns an integer file descriptor. *** procedure: dup->inport PORT/FD [NEWFD] Returns a new input port using the new file descriptor. *** procedure: dup->outport PORT/FD [NEWFD] Returns a new output port using the new file descriptor. *** procedure: dup PORT/FD [NEWFD] Returns a new port if PORT/FD is a port, with the same mode as the supplied port, otherwise returns an integer file descriptor. *** procedure: dup->port PORT/FD MODE [NEWFD] Returns a new port using the new file descriptor. MODE supplies a mode string for the port (*note open-file: File Ports.). *** procedure: setenv NAME VALUE Modifies the environment of the current process, which is also the default environment inherited by child processes. If VALUE is `#f', then NAME is removed from the environment. Otherwise, the string NAME=VALUE is added to the environment, replacing any existing string with name matching NAME. The return value is unspecified. *** procedure: truncate-file OBJ SIZE Truncates the file referred to by OBJ to at most SIZE bytes. OBJ can be a string containing a file name or an integer file descriptor or port open for output on the file. The underlying system calls are `truncate' and `ftruncate'. The return value is unspecified. *** procedure: setvbuf PORT MODE [SIZE] Set the buffering mode for PORT. MODE can be: `_IONBF' non-buffered `_IOLBF' line buffered `_IOFBF' block buffered, using a newly allocated buffer of SIZE bytes. However if SIZE is zero or unspecified, the port will be made non-buffered. This procedure should not be used after I/O has been performed with the port. Ports are usually block buffered by default, with a default buffer size. Procedures e.g., *Note open-file: File Ports, which accept a mode string allow `0' to be added to request an unbuffered port. *** procedure: fsync PORT/FD Copies any unwritten data for the specified output file descriptor to disk. If PORT/FD is a port, its buffer is flushed before the underlying file descriptor is fsync'd. The return value is unspecified. *** procedure: open-fdes PATH FLAGS [MODES] Similar to `open' but returns a file descriptor instead of a port. *** procedure: execle PATH ENV [ARG] ... Similar to `execl', but the environment of the new process is specified by ENV, which must be a list of strings as returned by the `environ' procedure. This procedure is currently implemented using the `execve' system call, but we call it `execle' because of its Scheme calling interface. *** procedure: strerror ERRNO Returns the Unix error message corresponding to ERRNO, an integer. *** procedure: primitive-exit [STATUS] Terminate the current process without unwinding the Scheme stack. This is would typically be useful after a fork. The exit status is STATUS if supplied, otherwise zero. *** procedure: times Returns an object with information about real and processor time. The following procedures accept such an object as an argument and return a selected component: `tms:clock' The current real time, expressed as time units relative to an arbitrary base. `tms:utime' The CPU time units used by the calling process. `tms:stime' The CPU time units used by the system on behalf of the calling process. `tms:cutime' The CPU time units used by terminated child processes of the calling process, whose status has been collected (e.g., using `waitpid'). `tms:cstime' Similarly, the CPU times units used by the system on behalf of terminated child processes. ** Removed: list-length ** Removed: list-append, list-append! ** Removed: list-reverse, list-reverse! ** array-map renamed to array-map! ** serial-array-map renamed to serial-array-map! ** catch doesn't take #f as first argument any longer Previously, it was possible to pass #f instead of a key to `catch'. That would cause `catch' to pass a jump buffer object to the procedure passed as second argument. The procedure could then use this jump buffer objekt as an argument to throw. This mechanism has been removed since its utility doesn't motivate the extra complexity it introduces. ** The `#/' notation for lists now provokes a warning message from Guile. This syntax will be removed from Guile in the near future. To disable the warning message, set the GUILE_HUSH environment variable to any non-empty value. ** The newline character now prints as `#\newline', following the normal Scheme notation, not `#\nl'. * Changes to the gh_ interface ** The gh_enter function now takes care of loading the Guile startup files. gh_enter works by calling scm_boot_guile; see the remarks below. ** Function: void gh_write (SCM x) Write the printed representation of the scheme object x to the current output port. Corresponds to the scheme level `write'. ** gh_list_length renamed to gh_length. ** vector handling routines Several major changes. In particular, gh_vector() now resembles (vector ...) (with a caveat -- see manual), and gh_make_vector() now exists and behaves like (make-vector ...). gh_vset() and gh_vref() have been renamed gh_vector_set_x() and gh_vector_ref(). Some missing vector-related gh_ functions have been implemented. ** pair and list routines Implemented several of the R4RS pair and list functions that were missing. ** gh_scm2doubles, gh_doubles2scm, gh_doubles2dvect New function. Converts double arrays back and forth between Scheme and C. * Changes to the scm_ interface ** The function scm_boot_guile now takes care of loading the startup files. Guile's primary initialization function, scm_boot_guile, now takes care of loading `boot-9.scm', in the `ice-9' module, to initialize Guile, define the module system, and put together some standard bindings. It also loads `init.scm', which is intended to hold site-specific initialization code. Since Guile cannot operate properly until boot-9.scm is loaded, there is no reason to separate loading boot-9.scm from Guile's other initialization processes. This job used to be done by scm_compile_shell_switches, which didn't make much sense; in particular, it meant that people using Guile for non-shell-like applications had to jump through hoops to get Guile initialized properly. ** The function scm_compile_shell_switches no longer loads the startup files. Now, Guile always loads the startup files, whenever it is initialized; see the notes above for scm_boot_guile and scm_load_startup_files. ** Function: scm_load_startup_files This new function takes care of loading Guile's initialization file (`boot-9.scm'), and the site initialization file, `init.scm'. Since this is always called by the Guile initialization process, it's probably not too useful to call this yourself, but it's there anyway. ** The semantics of smob marking have changed slightly. The smob marking function (the `mark' member of the scm_smobfuns structure) is no longer responsible for setting the mark bit on the smob. The generic smob handling code in the garbage collector will set this bit. The mark function need only ensure that any other objects the smob refers to get marked. Note that this change means that the smob's GC8MARK bit is typically already set upon entry to the mark function. Thus, marking functions which look like this: { if (SCM_GC8MARKP (ptr)) return SCM_BOOL_F; SCM_SETGC8MARK (ptr); ... mark objects to which the smob refers ... } are now incorrect, since they will return early, and fail to mark any other objects the smob refers to. Some code in the Guile library used to work this way. ** The semantics of the I/O port functions in scm_ptobfuns have changed. If you have implemented your own I/O port type, by writing the functions required by the scm_ptobfuns and then calling scm_newptob, you will need to change your functions slightly. The functions in a scm_ptobfuns structure now expect the port itself as their argument; they used to expect the `stream' member of the port's scm_port_table structure. This allows functions in an scm_ptobfuns structure to easily access the port's cell (and any flags it its CAR), and the port's scm_port_table structure. Guile now passes the I/O port itself as the `port' argument in the following scm_ptobfuns functions: int (*free) (SCM port); int (*fputc) (int, SCM port); int (*fputs) (char *, SCM port); scm_sizet (*fwrite) SCM_P ((char *ptr, scm_sizet size, scm_sizet nitems, SCM port)); int (*fflush) (SCM port); int (*fgetc) (SCM port); int (*fclose) (SCM port); The interfaces to the `mark', `print', `equalp', and `fgets' methods are unchanged. If you have existing code which defines its own port types, it is easy to convert your code to the new interface; simply apply SCM_STREAM to the port argument to yield the value you code used to expect. Note that since both the port and the stream have the same type in the C code --- they are both SCM values --- the C compiler will not remind you if you forget to update your scm_ptobfuns functions. ** Function: int scm_internal_select (int fds, SELECT_TYPE *rfds, SELECT_TYPE *wfds, SELECT_TYPE *efds, struct timeval *timeout); This is a replacement for the `select' function provided by the OS. It enables I/O blocking and sleeping to happen for one cooperative thread without blocking other threads. It also avoids busy-loops in these situations. It is intended that all I/O blocking and sleeping will finally go through this function. Currently, this function is only available on systems providing `gettimeofday' and `select'. ** Function: SCM scm_internal_stack_catch (SCM tag, scm_catch_body_t body, void *body_data, scm_catch_handler_t handler, void *handler_data) A new sibling to the other two C level `catch' functions scm_internal_catch and scm_internal_lazy_catch. Use it if you want the stack to be saved automatically into the variable `the-last-stack' (scm_the_last_stack_var) on error. This is necessary if you want to use advanced error reporting, such as calling scm_display_error and scm_display_backtrace. (They both take a stack object as argument.) ** Function: SCM scm_spawn_thread (scm_catch_body_t body, void *body_data, scm_catch_handler_t handler, void *handler_data) Spawns a new thread. It does a job similar to scm_call_with_new_thread but takes arguments more suitable when spawning threads from application C code. ** The hook scm_error_callback has been removed. It was originally intended as a way for the user to install his own error handler. But that method works badly since it intervenes between throw and catch, thereby changing the semantics of expressions like (catch #t ...). The correct way to do it is to use one of the C level catch functions in throw.c: scm_internal_catch/lazy_catch/stack_catch. ** Removed functions: scm_obj_length, scm_list_length, scm_list_append, scm_list_append_x, scm_list_reverse, scm_list_reverse_x ** New macros: SCM_LISTn where n is one of the integers 0-9. These can be used for pretty list creation from C. The idea is taken from Erick Gallesio's STk. ** scm_array_map renamed to scm_array_map_x ** mbstrings are now removed This means that the type codes scm_tc7_mb_string and scm_tc7_mb_substring has been removed. ** scm_gen_putc, scm_gen_puts, scm_gen_write, and scm_gen_getc have changed. Since we no longer support multi-byte strings, these I/O functions have been simplified, and renamed. Here are their old names, and their new names and arguments: scm_gen_putc -> void scm_putc (int c, SCM port); scm_gen_puts -> void scm_puts (char *s, SCM port); scm_gen_write -> void scm_lfwrite (char *ptr, scm_sizet size, SCM port); scm_gen_getc -> void scm_getc (SCM port); ** The macros SCM_TYP7D and SCM_TYP7SD has been removed. ** The macro SCM_TYP7S has taken the role of the old SCM_TYP7D SCM_TYP7S now masks away the bit which distinguishes substrings from strings. ** scm_catch_body_t: Backward incompatible change! Body functions to scm_internal_catch and friends do not any longer take a second argument. This is because it is no longer possible to pass a #f arg to catch. ** Calls to scm_protect_object and scm_unprotect now nest properly. The function scm_protect_object protects its argument from being freed by the garbage collector. scm_unprotect_object removes that protection. These functions now nest properly. That is, for every object O, there is a counter which scm_protect_object(O) increments and scm_unprotect_object(O) decrements, if the counter is greater than zero. Every object's counter is zero when it is first created. If an object's counter is greater than zero, the garbage collector will not reclaim its storage. This allows you to use scm_protect_object in your code without worrying that some other function you call will call scm_unprotect_object, and allow it to be freed. Assuming that the functions you call are well-behaved, and unprotect only those objects they protect, you can follow the same rule and have confidence that objects will be freed only at appropriate times. Changes in Guile 1.2 (released Tuesday, June 24 1997): * Changes to the distribution ** Nightly snapshots are now available from ftp.red-bean.com. The old server, ftp.cyclic.com, has been relinquished to its rightful owner. Nightly snapshots of the Guile development sources are now available via anonymous FTP from ftp.red-bean.com, as /pub/guile/guile-snap.tar.gz. Via the web, that's: ftp://ftp.red-bean.com/pub/guile/guile-snap.tar.gz For getit, that's: ftp.red-bean.com:/pub/guile/guile-snap.tar.gz ** To run Guile without installing it, the procedure has changed a bit. If you used a separate build directory to compile Guile, you'll need to include the build directory in SCHEME_LOAD_PATH, as well as the source directory. See the `INSTALL' file for examples. * Changes to the procedure for linking libguile with your programs ** The standard Guile load path for Scheme code now includes $(datadir)/guile (usually /usr/local/share/guile). This means that you can install your own Scheme files there, and Guile will find them. (Previous versions of Guile only checked a directory whose name contained the Guile version number, so you had to re-install or move your Scheme sources each time you installed a fresh version of Guile.) The load path also includes $(datadir)/guile/site; we recommend putting individual Scheme files there. If you want to install a package with multiple source files, create a directory for them under $(datadir)/guile. ** Guile 1.2 will now use the Rx regular expression library, if it is installed on your system. When you are linking libguile into your own programs, this means you will have to link against -lguile, -lqt (if you configured Guile with thread support), and -lrx. If you are using autoconf to generate configuration scripts for your application, the following lines should suffice to add the appropriate libraries to your link command: ### Find Rx, quickthreads and libguile. AC_CHECK_LIB(rx, main) AC_CHECK_LIB(qt, main) AC_CHECK_LIB(guile, scm_shell) The Guile 1.2 distribution does not contain sources for the Rx library, as Guile 1.0 did. If you want to use Rx, you'll need to retrieve it from a GNU FTP site and install it separately. * Changes to Scheme functions and syntax ** The dynamic linking features of Guile are now enabled by default. You can disable them by giving the `--disable-dynamic-linking' option to configure. (dynamic-link FILENAME) Find the object file denoted by FILENAME (a string) and link it into the running Guile application. When everything works out, return a Scheme object suitable for representing the linked object file. Otherwise an error is thrown. How object files are searched is system dependent. (dynamic-object? VAL) Determine whether VAL represents a dynamically linked object file. (dynamic-unlink DYNOBJ) Unlink the indicated object file from the application. DYNOBJ should be one of the values returned by `dynamic-link'. (dynamic-func FUNCTION DYNOBJ) Search the C function indicated by FUNCTION (a string or symbol) in DYNOBJ and return some Scheme object that can later be used with `dynamic-call' to actually call this function. Right now, these Scheme objects are formed by casting the address of the function to `long' and converting this number to its Scheme representation. (dynamic-call FUNCTION DYNOBJ) Call the C function indicated by FUNCTION and DYNOBJ. The function is passed no arguments and its return value is ignored. When FUNCTION is something returned by `dynamic-func', call that function and ignore DYNOBJ. When FUNCTION is a string (or symbol, etc.), look it up in DYNOBJ; this is equivalent to (dynamic-call (dynamic-func FUNCTION DYNOBJ) #f) Interrupts are deferred while the C function is executing (with SCM_DEFER_INTS/SCM_ALLOW_INTS). (dynamic-args-call FUNCTION DYNOBJ ARGS) Call the C function indicated by FUNCTION and DYNOBJ, but pass it some arguments and return its return value. The C function is expected to take two arguments and return an `int', just like `main': int c_func (int argc, char **argv); ARGS must be a list of strings and is converted into an array of `char *'. The array is passed in ARGV and its size in ARGC. The return value is converted to a Scheme number and returned from the call to `dynamic-args-call'. When dynamic linking is disabled or not supported on your system, the above functions throw errors, but they are still available. Here is a small example that works on GNU/Linux: (define libc-obj (dynamic-link "libc.so")) (dynamic-args-call 'rand libc-obj '()) See the file `libguile/DYNAMIC-LINKING' for additional comments. ** The #/ syntax for module names is depreciated, and will be removed in a future version of Guile. Instead of #/foo/bar/baz instead write (foo bar baz) The latter syntax is more consistent with existing Lisp practice. ** Guile now does fancier printing of structures. Structures are the underlying implementation for records, which in turn are used to implement modules, so all of these object now print differently and in a more informative way. The Scheme printer will examine the builtin variable *struct-printer* whenever it needs to print a structure object. When this variable is not `#f' it is deemed to be a procedure and will be applied to the structure object and the output port. When *struct-printer* is `#f' or the procedure return `#f' the structure object will be printed in the boring # form. This hook is used by some routines in ice-9/boot-9.scm to implement type specific printing routines. Please read the comments there about "printing structs". One of the more specific uses of structs are records. The printing procedure that could be passed to MAKE-RECORD-TYPE is now actually called. It should behave like a *struct-printer* procedure (described above). ** Guile now supports a new R4RS-compliant syntax for keywords. A token of the form #:NAME, where NAME has the same syntax as a Scheme symbol, is the external representation of the keyword named NAME. Keyword objects print using this syntax as well, so values containing keyword objects can be read back into Guile. When used in an expression, keywords are self-quoting objects. Guile suports this read syntax, and uses this print syntax, regardless of the current setting of the `keyword' read option. The `keyword' read option only controls whether Guile recognizes the `:NAME' syntax, which is incompatible with R4RS. (R4RS says such token represent symbols.) ** Guile has regular expression support again. Guile 1.0 included functions for matching regular expressions, based on the Rx library. In Guile 1.1, the Guile/Rx interface was removed to simplify the distribution, and thus Guile had no regular expression support. Guile 1.2 again supports the most commonly used functions, and supports all of SCSH's regular expression functions. If your system does not include a POSIX regular expression library, and you have not linked Guile with a third-party regexp library such as Rx, these functions will not be available. You can tell whether your Guile installation includes regular expression support by checking whether the `*features*' list includes the `regex' symbol. *** regexp functions By default, Guile supports POSIX extended regular expressions. That means that the characters `(', `)', `+' and `?' are special, and must be escaped if you wish to match the literal characters. This regular expression interface was modeled after that implemented by SCSH, the Scheme Shell. It is intended to be upwardly compatible with SCSH regular expressions. **** Function: string-match PATTERN STR [START] Compile the string PATTERN into a regular expression and compare it with STR. The optional numeric argument START specifies the position of STR at which to begin matching. `string-match' returns a "match structure" which describes what, if anything, was matched by the regular expression. *Note Match Structures::. If STR does not match PATTERN at all, `string-match' returns `#f'. Each time `string-match' is called, it must compile its PATTERN argument into a regular expression structure. This operation is expensive, which makes `string-match' inefficient if the same regular expression is used several times (for example, in a loop). For better performance, you can compile a regular expression in advance and then match strings against the compiled regexp. **** Function: make-regexp STR [FLAGS] Compile the regular expression described by STR, and return the compiled regexp structure. If STR does not describe a legal regular expression, `make-regexp' throws a `regular-expression-syntax' error. FLAGS may be the bitwise-or of one or more of the following: **** Constant: regexp/extended Use POSIX Extended Regular Expression syntax when interpreting STR. If not set, POSIX Basic Regular Expression syntax is used. If the FLAGS argument is omitted, we assume regexp/extended. **** Constant: regexp/icase Do not differentiate case. Subsequent searches using the returned regular expression will be case insensitive. **** Constant: regexp/newline Match-any-character operators don't match a newline. A non-matching list ([^...]) not containing a newline matches a newline. Match-beginning-of-line operator (^) matches the empty string immediately after a newline, regardless of whether the FLAGS passed to regexp-exec contain regexp/notbol. Match-end-of-line operator ($) matches the empty string immediately before a newline, regardless of whether the FLAGS passed to regexp-exec contain regexp/noteol. **** Function: regexp-exec REGEXP STR [START [FLAGS]] Match the compiled regular expression REGEXP against `str'. If the optional integer START argument is provided, begin matching from that position in the string. Return a match structure describing the results of the match, or `#f' if no match could be found. FLAGS may be the bitwise-or of one or more of the following: **** Constant: regexp/notbol The match-beginning-of-line operator always fails to match (but see the compilation flag regexp/newline above) This flag may be used when different portions of a string are passed to regexp-exec and the beginning of the string should not be interpreted as the beginning of the line. **** Constant: regexp/noteol The match-end-of-line operator always fails to match (but see the compilation flag regexp/newline above) **** Function: regexp? OBJ Return `#t' if OBJ is a compiled regular expression, or `#f' otherwise. Regular expressions are commonly used to find patterns in one string and replace them with the contents of another string. **** Function: regexp-substitute PORT MATCH [ITEM...] Write to the output port PORT selected contents of the match structure MATCH. Each ITEM specifies what should be written, and may be one of the following arguments: * A string. String arguments are written out verbatim. * An integer. The submatch with that number is written. * The symbol `pre'. The portion of the matched string preceding the regexp match is written. * The symbol `post'. The portion of the matched string following the regexp match is written. PORT may be `#f', in which case nothing is written; instead, `regexp-substitute' constructs a string from the specified ITEMs and returns that. **** Function: regexp-substitute/global PORT REGEXP TARGET [ITEM...] Similar to `regexp-substitute', but can be used to perform global substitutions on STR. Instead of taking a match structure as an argument, `regexp-substitute/global' takes two string arguments: a REGEXP string describing a regular expression, and a TARGET string which should be matched against this regular expression. Each ITEM behaves as in REGEXP-SUBSTITUTE, with the following exceptions: * A function may be supplied. When this function is called, it will be passed one argument: a match structure for a given regular expression match. It should return a string to be written out to PORT. * The `post' symbol causes `regexp-substitute/global' to recurse on the unmatched portion of STR. This *must* be supplied in order to perform global search-and-replace on STR; if it is not present among the ITEMs, then `regexp-substitute/global' will return after processing a single match. *** Match Structures A "match structure" is the object returned by `string-match' and `regexp-exec'. It describes which portion of a string, if any, matched the given regular expression. Match structures include: a reference to the string that was checked for matches; the starting and ending positions of the regexp match; and, if the regexp included any parenthesized subexpressions, the starting and ending positions of each submatch. In each of the regexp match functions described below, the `match' argument must be a match structure returned by a previous call to `string-match' or `regexp-exec'. Most of these functions return some information about the original target string that was matched against a regular expression; we will call that string TARGET for easy reference. **** Function: regexp-match? OBJ Return `#t' if OBJ is a match structure returned by a previous call to `regexp-exec', or `#f' otherwise. **** Function: match:substring MATCH [N] Return the portion of TARGET matched by subexpression number N. Submatch 0 (the default) represents the entire regexp match. If the regular expression as a whole matched, but the subexpression number N did not match, return `#f'. **** Function: match:start MATCH [N] Return the starting position of submatch number N. **** Function: match:end MATCH [N] Return the ending position of submatch number N. **** Function: match:prefix MATCH Return the unmatched portion of TARGET preceding the regexp match. **** Function: match:suffix MATCH Return the unmatched portion of TARGET following the regexp match. **** Function: match:count MATCH Return the number of parenthesized subexpressions from MATCH. Note that the entire regular expression match itself counts as a subexpression, and failed submatches are included in the count. **** Function: match:string MATCH Return the original TARGET string. *** Backslash Escapes Sometimes you will want a regexp to match characters like `*' or `$' exactly. For example, to check whether a particular string represents a menu entry from an Info node, it would be useful to match it against a regexp like `^* [^:]*::'. However, this won't work; because the asterisk is a metacharacter, it won't match the `*' at the beginning of the string. In this case, we want to make the first asterisk un-magic. You can do this by preceding the metacharacter with a backslash character `\'. (This is also called "quoting" the metacharacter, and is known as a "backslash escape".) When Guile sees a backslash in a regular expression, it considers the following glyph to be an ordinary character, no matter what special meaning it would ordinarily have. Therefore, we can make the above example work by changing the regexp to `^\* [^:]*::'. The `\*' sequence tells the regular expression engine to match only a single asterisk in the target string. Since the backslash is itself a metacharacter, you may force a regexp to match a backslash in the target string by preceding the backslash with itself. For example, to find variable references in a TeX program, you might want to find occurrences of the string `\let\' followed by any number of alphabetic characters. The regular expression `\\let\\[A-Za-z]*' would do this: the double backslashes in the regexp each match a single backslash in the target string. **** Function: regexp-quote STR Quote each special character found in STR with a backslash, and return the resulting string. *Very important:* Using backslash escapes in Guile source code (as in Emacs Lisp or C) can be tricky, because the backslash character has special meaning for the Guile reader. For example, if Guile encounters the character sequence `\n' in the middle of a string while processing Scheme code, it replaces those characters with a newline character. Similarly, the character sequence `\t' is replaced by a horizontal tab. Several of these "escape sequences" are processed by the Guile reader before your code is executed. Unrecognized escape sequences are ignored: if the characters `\*' appear in a string, they will be translated to the single character `*'. This translation is obviously undesirable for regular expressions, since we want to be able to include backslashes in a string in order to escape regexp metacharacters. Therefore, to make sure that a backslash is preserved in a string in your Guile program, you must use *two* consecutive backslashes: (define Info-menu-entry-pattern (make-regexp "^\\* [^:]*")) The string in this example is preprocessed by the Guile reader before any code is executed. The resulting argument to `make-regexp' is the string `^\* [^:]*', which is what we really want. This also means that in order to write a regular expression that matches a single backslash character, the regular expression string in the source code must include *four* backslashes. Each consecutive pair of backslashes gets translated by the Guile reader to a single backslash, and the resulting double-backslash is interpreted by the regexp engine as matching a single backslash character. Hence: (define tex-variable-pattern (make-regexp "\\\\let\\\\=[A-Za-z]*")) The reason for the unwieldiness of this syntax is historical. Both regular expression pattern matchers and Unix string processing systems have traditionally used backslashes with the special meanings described above. The POSIX regular expression specification and ANSI C standard both require these semantics. Attempting to abandon either convention would cause other kinds of compatibility problems, possibly more severe ones. Therefore, without extending the Scheme reader to support strings with different quoting conventions (an ungainly and confusing extension when implemented in other languages), we must adhere to this cumbersome escape syntax. * Changes to the gh_ interface * Changes to the scm_ interface * Changes to system call interfaces: ** The value returned by `raise' is now unspecified. It throws an exception if an error occurs. *** A new procedure `sigaction' can be used to install signal handlers (sigaction signum [action] [flags]) signum is the signal number, which can be specified using the value of SIGINT etc. If action is omitted, sigaction returns a pair: the CAR is the current signal hander, which will be either an integer with the value SIG_DFL (default action) or SIG_IGN (ignore), or the Scheme procedure which handles the signal, or #f if a non-Scheme procedure handles the signal. The CDR contains the current sigaction flags for the handler. If action is provided, it is installed as the new handler for signum. action can be a Scheme procedure taking one argument, or the value of SIG_DFL (default action) or SIG_IGN (ignore), or #f to restore whatever signal handler was installed before sigaction was first used. Flags can optionally be specified for the new handler (SA_RESTART is always used if the system provides it, so need not be specified.) The return value is a pair with information about the old handler as described above. This interface does not provide access to the "signal blocking" facility. Maybe this is not needed, since the thread support may provide solutions to the problem of consistent access to data structures. *** A new procedure `flush-all-ports' is equivalent to running `force-output' on every port open for output. ** Guile now provides information on how it was built, via the new global variable, %guile-build-info. This variable records the values of the standard GNU makefile directory variables as an assocation list, mapping variable names (symbols) onto directory paths (strings). For example, to find out where the Guile link libraries were installed, you can say: guile -c "(display (assq-ref %guile-build-info 'libdir)) (newline)" * Changes to the scm_ interface ** The new function scm_handle_by_message_noexit is just like the existing scm_handle_by_message function, except that it doesn't call exit to terminate the process. Instead, it prints a message and just returns #f. This might be a more appropriate catch-all handler for new dynamic roots and threads. Changes in Guile 1.1 (released Friday, May 16 1997): * Changes to the distribution. The Guile 1.0 distribution has been split up into several smaller pieces: guile-core --- the Guile interpreter itself. guile-tcltk --- the interface between the Guile interpreter and Tcl/Tk; Tcl is an interpreter for a stringy language, and Tk is a toolkit for building graphical user interfaces. guile-rgx-ctax --- the interface between Guile and the Rx regular expression matcher, and the translator for the Ctax programming language. These are packaged together because the Ctax translator uses Rx to parse Ctax source code. This NEWS file describes the changes made to guile-core since the 1.0 release. We no longer distribute the documentation, since it was either out of date, or incomplete. As soon as we have current documentation, we will distribute it. * Changes to the stand-alone interpreter ** guile now accepts command-line arguments compatible with SCSH, Olin Shivers' Scheme Shell. In general, arguments are evaluated from left to right, but there are exceptions. The following switches stop argument processing, and stash all remaining command-line arguments as the value returned by the (command-line) function. -s SCRIPT load Scheme source code from FILE, and exit -c EXPR evalute Scheme expression EXPR, and exit -- stop scanning arguments; run interactively The switches below are processed as they are encountered. -l FILE load Scheme source code from FILE -e FUNCTION after reading script, apply FUNCTION to command line arguments -ds do -s script at this point --emacs enable Emacs protocol (experimental) -h, --help display this help and exit -v, --version display version information and exit \ read arguments from following script lines So, for example, here is a Guile script named `ekko' (thanks, Olin) which re-implements the traditional "echo" command: #!/usr/local/bin/guile -s !# (define (main args) (map (lambda (arg) (display arg) (display " ")) (cdr args)) (newline)) (main (command-line)) Suppose we invoke this script as follows: ekko a speckled gecko Through the magic of Unix script processing (triggered by the `#!' token at the top of the file), /usr/local/bin/guile receives the following list of command-line arguments: ("-s" "./ekko" "a" "speckled" "gecko") Unix inserts the name of the script after the argument specified on the first line of the file (in this case, "-s"), and then follows that with the arguments given to the script. Guile loads the script, which defines the `main' function, and then applies it to the list of remaining command-line arguments, ("a" "speckled" "gecko"). In Unix, the first line of a script file must take the following form: #!INTERPRETER ARGUMENT where INTERPRETER is the absolute filename of the interpreter executable, and ARGUMENT is a single command-line argument to pass to the interpreter. You may only pass one argument to the interpreter, and its length is limited. These restrictions can be annoying to work around, so Guile provides a general mechanism (borrowed from, and compatible with, SCSH) for circumventing them. If the ARGUMENT in a Guile script is a single backslash character, `\', Guile will open the script file, parse arguments from its second and subsequent lines, and replace the `\' with them. So, for example, here is another implementation of the `ekko' script: #!/usr/local/bin/guile \ -e main -s !# (define (main args) (for-each (lambda (arg) (display arg) (display " ")) (cdr args)) (newline)) If the user invokes this script as follows: ekko a speckled gecko Unix expands this into /usr/local/bin/guile \ ekko a speckled gecko When Guile sees the `\' argument, it replaces it with the arguments read from the second line of the script, producing: /usr/local/bin/guile -e main -s ekko a speckled gecko This tells Guile to load the `ekko' script, and apply the function `main' to the argument list ("a" "speckled" "gecko"). Here is how Guile parses the command-line arguments: - Each space character terminates an argument. This means that two spaces in a row introduce an empty-string argument. - The tab character is not permitted (unless you quote it with the backslash character, as described below), to avoid confusion. - The newline character terminates the sequence of arguments, and will also terminate a final non-empty argument. (However, a newline following a space will not introduce a final empty-string argument; it only terminates the argument list.) - The backslash character is the escape character. It escapes backslash, space, tab, and newline. The ANSI C escape sequences like \n and \t are also supported. These produce argument constituents; the two-character combination \n doesn't act like a terminating newline. The escape sequence \NNN for exactly three octal digits reads as the character whose ASCII code is NNN. As above, characters produced this way are argument constituents. Backslash followed by other characters is not allowed. * Changes to the procedure for linking libguile with your programs ** Guile now builds and installs a shared guile library, if your system support shared libraries. (It still builds a static library on all systems.) Guile automatically detects whether your system supports shared libraries. To prevent Guile from buildisg shared libraries, pass the `--disable-shared' flag to the configure script. Guile takes longer to compile when it builds shared libraries, because it must compile every file twice --- once to produce position- independent object code, and once to produce normal object code. ** The libthreads library has been merged into libguile. To link a program against Guile, you now need only link against -lguile and -lqt; -lthreads is no longer needed. If you are using autoconf to generate configuration scripts for your application, the following lines should suffice to add the appropriate libraries to your link command: ### Find quickthreads and libguile. AC_CHECK_LIB(qt, main) AC_CHECK_LIB(guile, scm_shell) * Changes to Scheme functions ** Guile Scheme's special syntax for keyword objects is now optional, and disabled by default. The syntax variation from R4RS made it difficult to port some interesting packages to Guile. The routines which accepted keyword arguments (mostly in the module system) have been modified to also accept symbols whose names begin with `:'. To change the keyword syntax, you must first import the (ice-9 debug) module: (use-modules (ice-9 debug)) Then you can enable the keyword syntax as follows: (read-set! keywords 'prefix) To disable keyword syntax, do this: (read-set! keywords #f) ** Many more primitive functions accept shared substrings as arguments. In the past, these functions required normal, mutable strings as arguments, although they never made use of this restriction. ** The uniform array functions now operate on byte vectors. These functions are `array-fill!', `serial-array-copy!', `array-copy!', `serial-array-map', `array-map', `array-for-each', and `array-index-map!'. ** The new functions `trace' and `untrace' implement simple debugging support for Scheme functions. The `trace' function accepts any number of procedures as arguments, and tells the Guile interpreter to display each procedure's name and arguments each time the procedure is invoked. When invoked with no arguments, `trace' returns the list of procedures currently being traced. The `untrace' function accepts any number of procedures as arguments, and tells the Guile interpreter not to trace them any more. When invoked with no arguments, `untrace' untraces all curretly traced procedures. The tracing in Guile has an advantage over most other systems: we don't create new procedure objects, but mark the procedure objects themselves. This means that anonymous and internal procedures can be traced. ** The function `assert-repl-prompt' has been renamed to `set-repl-prompt!'. It takes one argument, PROMPT. - If PROMPT is #f, the Guile read-eval-print loop will not prompt. - If PROMPT is a string, we use it as a prompt. - If PROMPT is a procedure accepting no arguments, we call it, and display the result as a prompt. - Otherwise, we display "> ". ** The new function `eval-string' reads Scheme expressions from a string and evaluates them, returning the value of the last expression in the string. If the string contains no expressions, it returns an unspecified value. ** The new function `thunk?' returns true iff its argument is a procedure of zero arguments. ** `defined?' is now a builtin function, instead of syntax. This means that its argument should be quoted. It returns #t iff its argument is bound in the current module. ** The new syntax `use-modules' allows you to add new modules to your environment without re-typing a complete `define-module' form. It accepts any number of module names as arguments, and imports their public bindings into the current module. ** The new function (module-defined? NAME MODULE) returns true iff NAME, a symbol, is defined in MODULE, a module object. ** The new function `builtin-bindings' creates and returns a hash table containing copies of all the root module's bindings. ** The new function `builtin-weak-bindings' does the same as `builtin-bindings', but creates a doubly-weak hash table. ** The `equal?' function now considers variable objects to be equivalent if they have the same name and the same value. ** The new function `command-line' returns the command-line arguments given to Guile, as a list of strings. When using guile as a script interpreter, `command-line' returns the script's arguments; those processed by the interpreter (like `-s' or `-c') are omitted. (In other words, you get the normal, expected behavior.) Any application that uses scm_shell to process its command-line arguments gets this behavior as well. ** The new function `load-user-init' looks for a file called `.guile' in the user's home directory, and loads it if it exists. This is mostly for use by the code generated by scm_compile_shell_switches, but we thought it might also be useful in other circumstances. ** The new function `log10' returns the base-10 logarithm of its argument. ** Changes to I/O functions *** The functions `read', `primitive-load', `read-and-eval!', and `primitive-load-path' no longer take optional arguments controlling case insensitivity and a `#' parser. Case sensitivity is now controlled by a read option called `case-insensitive'. The user can add new `#' syntaxes with the `read-hash-extend' function (see below). *** The new function `read-hash-extend' allows the user to change the syntax of Guile Scheme in a somewhat controlled way. (read-hash-extend CHAR PROC) When parsing S-expressions, if we read a `#' character followed by the character CHAR, use PROC to parse an object from the stream. If PROC is #f, remove any parsing procedure registered for CHAR. The reader applies PROC to two arguments: CHAR and an input port. *** The new functions read-delimited and read-delimited! provide a general mechanism for doing delimited input on streams. (read-delimited DELIMS [PORT HANDLE-DELIM]) Read until we encounter one of the characters in DELIMS (a string), or end-of-file. PORT is the input port to read from; it defaults to the current input port. The HANDLE-DELIM parameter determines how the terminating character is handled; it should be one of the following symbols: 'trim omit delimiter from result 'peek leave delimiter character in input stream 'concat append delimiter character to returned value 'split return a pair: (RESULT . TERMINATOR) HANDLE-DELIM defaults to 'peek. (read-delimited! DELIMS BUF [PORT HANDLE-DELIM START END]) A side-effecting variant of `read-delimited'. The data is written into the string BUF at the indices in the half-open interval [START, END); the default interval is the whole string: START = 0 and END = (string-length BUF). The values of START and END must specify a well-defined interval in BUF, i.e. 0 <= START <= END <= (string-length BUF). It returns NBYTES, the number of bytes read. If the buffer filled up without a delimiter character being found, it returns #f. If the port is at EOF when the read starts, it returns the EOF object. If an integer is returned (i.e., the read is successfully terminated by reading a delimiter character), then the HANDLE-DELIM parameter determines how to handle the terminating character. It is described above, and defaults to 'peek. (The descriptions of these functions were borrowed from the SCSH manual, by Olin Shivers and Brian Carlstrom.) *** The `%read-delimited!' function is the primitive used to implement `read-delimited' and `read-delimited!'. (%read-delimited! DELIMS BUF GOBBLE? [PORT START END]) This returns a pair of values: (TERMINATOR . NUM-READ). - TERMINATOR describes why the read was terminated. If it is a character or the eof object, then that is the value that terminated the read. If it is #f, the function filled the buffer without finding a delimiting character. - NUM-READ is the number of characters read into BUF. If the read is successfully terminated by reading a delimiter character, then the gobble? parameter determines what to do with the terminating character. If true, the character is removed from the input stream; if false, the character is left in the input stream where a subsequent read operation will retrieve it. In either case, the character is also the first value returned by the procedure call. (The descriptions of this function was borrowed from the SCSH manual, by Olin Shivers and Brian Carlstrom.) *** The `read-line' and `read-line!' functions have changed; they now trim the terminator by default; previously they appended it to the returned string. For the old behavior, use (read-line PORT 'concat). *** The functions `uniform-array-read!' and `uniform-array-write!' now take new optional START and END arguments, specifying the region of the array to read and write. *** The `ungetc-char-ready?' function has been removed. We feel it's inappropriate for an interface to expose implementation details this way. ** Changes to the Unix library and system call interface *** The new fcntl function provides access to the Unix `fcntl' system call. (fcntl PORT COMMAND VALUE) Apply COMMAND to PORT's file descriptor, with VALUE as an argument. Values for COMMAND are: F_DUPFD duplicate a file descriptor F_GETFD read the descriptor's close-on-exec flag F_SETFD set the descriptor's close-on-exec flag to VALUE F_GETFL read the descriptor's flags, as set on open F_SETFL set the descriptor's flags, as set on open to VALUE F_GETOWN return the process ID of a socket's owner, for SIGIO F_SETOWN set the process that owns a socket to VALUE, for SIGIO FD_CLOEXEC not sure what this is For details, see the documentation for the fcntl system call. *** The arguments to `select' have changed, for compatibility with SCSH. The TIMEOUT parameter may now be non-integral, yielding the expected behavior. The MILLISECONDS parameter has been changed to MICROSECONDS, to more closely resemble the underlying system call. The RVEC, WVEC, and EVEC arguments can now be vectors; the type of the corresponding return set will be the same. *** The arguments to the `mknod' system call have changed. They are now: (mknod PATH TYPE PERMS DEV) Create a new file (`node') in the file system. PATH is the name of the file to create. TYPE is the kind of file to create; it should be 'fifo, 'block-special, or 'char-special. PERMS specifies the permission bits to give the newly created file. If TYPE is 'block-special or 'char-special, DEV specifies which device the special file refers to; its interpretation depends on the kind of special file being created. *** The `fork' function has been renamed to `primitive-fork', to avoid clashing with various SCSH forks. *** The `recv' and `recvfrom' functions have been renamed to `recv!' and `recvfrom!'. They no longer accept a size for a second argument; you must pass a string to hold the received value. They no longer return the buffer. Instead, `recv' returns the length of the message received, and `recvfrom' returns a pair containing the packet's length and originating address. *** The file descriptor datatype has been removed, as have the `read-fd', `write-fd', `close', `lseek', and `dup' functions. We plan to replace these functions with a SCSH-compatible interface. *** The `create' function has been removed; it's just a special case of `open'. *** There are new functions to break down process termination status values. In the descriptions below, STATUS is a value returned by `waitpid'. (status:exit-val STATUS) If the child process exited normally, this function returns the exit code for the child process (i.e., the value passed to exit, or returned from main). If the child process did not exit normally, this function returns #f. (status:stop-sig STATUS) If the child process was suspended by a signal, this function returns the signal that suspended the child. Otherwise, it returns #f. (status:term-sig STATUS) If the child process terminated abnormally, this function returns the signal that terminated the child. Otherwise, this function returns false. POSIX promises that exactly one of these functions will return true on a valid STATUS value. These functions are compatible with SCSH. *** There are new accessors and setters for the broken-out time vectors returned by `localtime', `gmtime', and that ilk. They are: Component Accessor Setter ========================= ============ ============ seconds tm:sec set-tm:sec minutes tm:min set-tm:min hours tm:hour set-tm:hour day of the month tm:mday set-tm:mday month tm:mon set-tm:mon year tm:year set-tm:year day of the week tm:wday set-tm:wday day in the year tm:yday set-tm:yday daylight saving time tm:isdst set-tm:isdst GMT offset, seconds tm:gmtoff set-tm:gmtoff name of time zone tm:zone set-tm:zone *** There are new accessors for the vectors returned by `uname', describing the host system: Component Accessor ============================================== ================ name of the operating system implementation utsname:sysname network name of this machine utsname:nodename release level of the operating system utsname:release version level of the operating system utsname:version machine hardware platform utsname:machine *** There are new accessors for the vectors returned by `getpw', `getpwnam', `getpwuid', and `getpwent', describing entries from the system's user database: Component Accessor ====================== ================= user name passwd:name user password passwd:passwd user id passwd:uid group id passwd:gid real name passwd:gecos home directory passwd:dir shell program passwd:shell *** There are new accessors for the vectors returned by `getgr', `getgrnam', `getgrgid', and `getgrent', describing entries from the system's group database: Component Accessor ======================= ============ group name group:name group password group:passwd group id group:gid group members group:mem *** There are new accessors for the vectors returned by `gethost', `gethostbyaddr', `gethostbyname', and `gethostent', describing internet hosts: Component Accessor ========================= =============== official name of host hostent:name alias list hostent:aliases host address type hostent:addrtype length of address hostent:length list of addresses hostent:addr-list *** There are new accessors for the vectors returned by `getnet', `getnetbyaddr', `getnetbyname', and `getnetent', describing internet networks: Component Accessor ========================= =============== official name of net netent:name alias list netent:aliases net number type netent:addrtype net number netent:net *** There are new accessors for the vectors returned by `getproto', `getprotobyname', `getprotobynumber', and `getprotoent', describing internet protocols: Component Accessor ========================= =============== official protocol name protoent:name alias list protoent:aliases protocol number protoent:proto *** There are new accessors for the vectors returned by `getserv', `getservbyname', `getservbyport', and `getservent', describing internet protocols: Component Accessor ========================= =============== official service name servent:name alias list servent:aliases port number servent:port protocol to use servent:proto *** There are new accessors for the sockaddr structures returned by `accept', `getsockname', `getpeername', `recvfrom!': Component Accessor ======================================== =============== address format (`family') sockaddr:fam path, for file domain addresses sockaddr:path address, for internet domain addresses sockaddr:addr TCP or UDP port, for internet sockaddr:port *** The `getpwent', `getgrent', `gethostent', `getnetent', `getprotoent', and `getservent' functions now return #f at the end of the user database. (They used to throw an exception.) Note that calling MUMBLEent function is equivalent to calling the corresponding MUMBLE function with no arguments. *** The `setpwent', `setgrent', `sethostent', `setnetent', `setprotoent', and `setservent' routines now take no arguments. *** The `gethost', `getproto', `getnet', and `getserv' functions now provide more useful information when they throw an exception. *** The `lnaof' function has been renamed to `inet-lnaof'. *** Guile now claims to have the `current-time' feature. *** The `mktime' function now takes an optional second argument ZONE, giving the time zone to use for the conversion. ZONE should be a string, in the same format as expected for the "TZ" environment variable. *** The `strptime' function now returns a pair (TIME . COUNT), where TIME is the parsed time as a vector, and COUNT is the number of characters from the string left unparsed. This function used to return the remaining characters as a string. *** The `gettimeofday' function has replaced the old `time+ticks' function. The return value is now (SECONDS . MICROSECONDS); the fractional component is no longer expressed in "ticks". *** The `ticks/sec' constant has been removed, in light of the above change. * Changes to the gh_ interface ** gh_eval_str() now returns an SCM object which is the result of the evaluation ** gh_scm2str() now copies the Scheme data to a caller-provided C array ** gh_scm2newstr() now makes a C array, copies the Scheme data to it, and returns the array ** gh_scm2str0() is gone: there is no need to distinguish null-terminated from non-null-terminated, since gh_scm2newstr() allows the user to interpret the data both ways. * Changes to the scm_ interface ** The new function scm_symbol_value0 provides an easy way to get a symbol's value from C code: SCM scm_symbol_value0 (char *NAME) Return the value of the symbol named by the null-terminated string NAME in the current module. If the symbol named NAME is unbound in the current module, return SCM_UNDEFINED. ** The new function scm_sysintern0 creates new top-level variables, without assigning them a value. SCM scm_sysintern0 (char *NAME) Create a new Scheme top-level variable named NAME. NAME is a null-terminated string. Return the variable's value cell. ** The function scm_internal_catch is the guts of catch. It handles all the mechanics of setting up a catch target, invoking the catch body, and perhaps invoking the handler if the body does a throw. The function is designed to be usable from C code, but is general enough to implement all the semantics Guile Scheme expects from throw. TAG is the catch tag. Typically, this is a symbol, but this function doesn't actually care about that. BODY is a pointer to a C function which runs the body of the catch; this is the code you can throw from. We call it like this: BODY (BODY_DATA, JMPBUF) where: BODY_DATA is just the BODY_DATA argument we received; we pass it through to BODY as its first argument. The caller can make BODY_DATA point to anything useful that BODY might need. JMPBUF is the Scheme jmpbuf object corresponding to this catch, which we have just created and initialized. HANDLER is a pointer to a C function to deal with a throw to TAG, should one occur. We call it like this: HANDLER (HANDLER_DATA, THROWN_TAG, THROW_ARGS) where HANDLER_DATA is the HANDLER_DATA argument we recevied; it's the same idea as BODY_DATA above. THROWN_TAG is the tag that the user threw to; usually this is TAG, but it could be something else if TAG was #t (i.e., a catch-all), or the user threw to a jmpbuf. THROW_ARGS is the list of arguments the user passed to the THROW function. BODY_DATA is just a pointer we pass through to BODY. HANDLER_DATA is just a pointer we pass through to HANDLER. We don't actually use either of those pointers otherwise ourselves. The idea is that, if our caller wants to communicate something to BODY or HANDLER, it can pass a pointer to it as MUMBLE_DATA, which BODY and HANDLER can then use. Think of it as a way to make BODY and HANDLER closures, not just functions; MUMBLE_DATA points to the enclosed variables. Of course, it's up to the caller to make sure that any data a MUMBLE_DATA needs is protected from GC. A common way to do this is to make MUMBLE_DATA a pointer to data stored in an automatic structure variable; since the collector must scan the stack for references anyway, this assures that any references in MUMBLE_DATA will be found. ** The new function scm_internal_lazy_catch is exactly like scm_internal_catch, except: - It does not unwind the stack (this is the major difference). - If handler returns, its value is returned from the throw. - BODY always receives #f as its JMPBUF argument (since there's no jmpbuf associated with a lazy catch, because we don't unwind the stack.) ** scm_body_thunk is a new body function you can pass to scm_internal_catch if you want the body to be like Scheme's `catch' --- a thunk, or a function of one argument if the tag is #f. BODY_DATA is a pointer to a scm_body_thunk_data structure, which contains the Scheme procedure to invoke as the body, and the tag we're catching. If the tag is #f, then we pass JMPBUF (created by scm_internal_catch) to the body procedure; otherwise, the body gets no arguments. ** scm_handle_by_proc is a new handler function you can pass to scm_internal_catch if you want the handler to act like Scheme's catch --- call a procedure with the tag and the throw arguments. If the user does a throw to this catch, this function runs a handler procedure written in Scheme. HANDLER_DATA is a pointer to an SCM variable holding the Scheme procedure object to invoke. It ought to be a pointer to an automatic variable (i.e., one living on the stack), or the procedure object should be otherwise protected from GC. ** scm_handle_by_message is a new handler function to use with `scm_internal_catch' if you want Guile to print a message and die. It's useful for dealing with throws to uncaught keys at the top level. HANDLER_DATA, if non-zero, is assumed to be a char * pointing to a message header to print; if zero, we use "guile" instead. That text is followed by a colon, then the message described by ARGS. ** The return type of scm_boot_guile is now void; the function does not return a value, and indeed, never returns at all. ** The new function scm_shell makes it easy for user applications to process command-line arguments in a way that is compatible with the stand-alone guile interpreter (which is in turn compatible with SCSH, the Scheme shell). To use the scm_shell function, first initialize any guile modules linked into your application, and then call scm_shell with the values of ARGC and ARGV your `main' function received. scm_shell will add any SCSH-style meta-arguments from the top of the script file to the argument vector, and then process the command-line arguments. This generally means loading a script file or starting up an interactive command interpreter. For details, see "Changes to the stand-alone interpreter" above. ** The new functions scm_get_meta_args and scm_count_argv help you implement the SCSH-style meta-argument, `\'. char **scm_get_meta_args (int ARGC, char **ARGV) If the second element of ARGV is a string consisting of a single backslash character (i.e. "\\" in Scheme notation), open the file named by the following argument, parse arguments from it, and return the spliced command line. The returned array is terminated by a null pointer. For details of argument parsing, see above, under "guile now accepts command-line arguments compatible with SCSH..." int scm_count_argv (char **ARGV) Count the arguments in ARGV, assuming it is terminated by a null pointer. For an example of how these functions might be used, see the source code for the function scm_shell in libguile/script.c. You will usually want to use scm_shell instead of calling this function yourself. ** The new function scm_compile_shell_switches turns an array of command-line arguments into Scheme code to carry out the actions they describe. Given ARGC and ARGV, it returns a Scheme expression to evaluate, and calls scm_set_program_arguments to make any remaining command-line arguments available to the Scheme code. For example, given the following arguments: -e main -s ekko a speckled gecko scm_set_program_arguments will return the following expression: (begin (load "ekko") (main (command-line)) (quit)) You will usually want to use scm_shell instead of calling this function yourself. ** The function scm_shell_usage prints a usage message appropriate for an interpreter that uses scm_compile_shell_switches to handle its command-line arguments. void scm_shell_usage (int FATAL, char *MESSAGE) Print a usage message to the standard error output. If MESSAGE is non-zero, write it before the usage message, followed by a newline. If FATAL is non-zero, exit the process, using FATAL as the termination status. (If you want to be compatible with Guile, always use 1 as the exit status when terminating due to command-line usage problems.) You will usually want to use scm_shell instead of calling this function yourself. ** scm_eval_0str now returns SCM_UNSPECIFIED if the string contains no expressions. It used to return SCM_EOL. Earth-shattering. ** The macros for declaring scheme objects in C code have been rearranged slightly. They are now: SCM_SYMBOL (C_NAME, SCHEME_NAME) Declare a static SCM variable named C_NAME, and initialize it to point to the Scheme symbol whose name is SCHEME_NAME. C_NAME should be a C identifier, and SCHEME_NAME should be a C string. SCM_GLOBAL_SYMBOL (C_NAME, SCHEME_NAME) Just like SCM_SYMBOL, but make C_NAME globally visible. SCM_VCELL (C_NAME, SCHEME_NAME) Create a global variable at the Scheme level named SCHEME_NAME. Declare a static SCM variable named C_NAME, and initialize it to point to the Scheme variable's value cell. SCM_GLOBAL_VCELL (C_NAME, SCHEME_NAME) Just like SCM_VCELL, but make C_NAME globally visible. The `guile-snarf' script writes initialization code for these macros to its standard output, given C source code as input. The SCM_GLOBAL macro is gone. ** The scm_read_line and scm_read_line_x functions have been replaced by Scheme code based on the %read-delimited! procedure (known to C code as scm_read_delimited_x). See its description above for more information. ** The function scm_sys_open has been renamed to scm_open. It now returns a port instead of an FD object. * The dynamic linking support has changed. For more information, see libguile/DYNAMIC-LINKING. Guile 1.0b3 User-visible changes from Thursday, September 5, 1996 until Guile 1.0 (Sun 5 Jan 1997): * Changes to the 'guile' program: ** Guile now loads some new files when it starts up. Guile first searches the load path for init.scm, and loads it if found. Then, if Guile is not being used to execute a script, and the user's home directory contains a file named `.guile', Guile loads that. ** You can now use Guile as a shell script interpreter. To paraphrase the SCSH manual: When Unix tries to execute an executable file whose first two characters are the `#!', it treats the file not as machine code to be directly executed by the native processor, but as source code to be executed by some interpreter. The interpreter to use is specified immediately after the #! sequence on the first line of the source file. The kernel reads in the name of the interpreter, and executes that instead. It passes the interpreter the source filename as its first argument, with the original arguments following. Consult the Unix man page for the `exec' system call for more information. Now you can use Guile as an interpreter, using a mechanism which is a compatible subset of that provided by SCSH. Guile now recognizes a '-s' command line switch, whose argument is the name of a file of Scheme code to load. It also treats the two characters `#!' as the start of a comment, terminated by `!#'. Thus, to make a file of Scheme code directly executable by Unix, insert the following two lines at the top of the file: #!/usr/local/bin/guile -s !# Guile treats the argument of the `-s' command-line switch as the name of a file of Scheme code to load, and treats the sequence `#!' as the start of a block comment, terminated by `!#'. For example, here's a version of 'echo' written in Scheme: #!/usr/local/bin/guile -s !# (let loop ((args (cdr (program-arguments)))) (if (pair? args) (begin (display (car args)) (if (pair? (cdr args)) (display " ")) (loop (cdr args))))) (newline) Why does `#!' start a block comment terminated by `!#', instead of the end of the line? That is the notation SCSH uses, and although we don't yet support the other SCSH features that motivate that choice, we would like to be backward-compatible with any existing Guile scripts once we do. Furthermore, if the path to Guile on your system is too long for your kernel, you can start the script with this horrible hack: #!/bin/sh exec /really/long/path/to/guile -s "$0" ${1+"$@"} !# Note that some very old Unix systems don't support the `#!' syntax. ** You can now run Guile without installing it. Previous versions of the interactive Guile interpreter (`guile') couldn't start up unless Guile's Scheme library had been installed; they used the value of the environment variable `SCHEME_LOAD_PATH' later on in the startup process, but not to find the startup code itself. Now Guile uses `SCHEME_LOAD_PATH' in all searches for Scheme code. To run Guile without installing it, build it in the normal way, and then set the environment variable `SCHEME_LOAD_PATH' to a colon-separated list of directories, including the top-level directory of the Guile sources. For example, if you unpacked Guile so that the full filename of this NEWS file is /home/jimb/guile-1.0b3/NEWS, then you might say export SCHEME_LOAD_PATH=/home/jimb/my-scheme:/home/jimb/guile-1.0b3 ** Guile's read-eval-print loop no longer prints # results. If the user wants to see this, she can evaluate the expression (assert-repl-print-unspecified #t), perhaps in her startup file. ** Guile no longer shows backtraces by default when an error occurs; however, it does display a message saying how to get one, and how to request that they be displayed by default. After an error, evaluate (backtrace) to see a backtrace, and (debug-enable 'backtrace) to see them by default. * Changes to Guile Scheme: ** Guile now distinguishes between #f and the empty list. This is for compatibility with the IEEE standard, the (possibly) upcoming Revised^5 Report on Scheme, and many extant Scheme implementations. Guile used to have #f and '() denote the same object, to make Scheme's type system more compatible with Emacs Lisp's. However, the change caused too much trouble for Scheme programmers, and we found another way to reconcile Emacs Lisp with Scheme that didn't require this. ** Guile's delq, delv, delete functions, and their destructive counterparts, delq!, delv!, and delete!, now remove all matching elements from the list, not just the first. This matches the behavior of the corresponding Emacs Lisp functions, and (I believe) the Maclisp functions which inspired them. I recognize that this change may break code in subtle ways, but it seems best to make the change before the FSF's first Guile release, rather than after. ** The compiled-library-path function has been deleted from libguile. ** The facilities for loading Scheme source files have changed. *** The variable %load-path now tells Guile which directories to search for Scheme code. Its value is a list of strings, each of which names a directory. *** The variable %load-extensions now tells Guile which extensions to try appending to a filename when searching the load path. Its value is a list of strings. Its default value is ("" ".scm"). *** (%search-load-path FILENAME) searches the directories listed in the value of the %load-path variable for a Scheme file named FILENAME, with all the extensions listed in %load-extensions. If it finds a match, then it returns its full filename. If FILENAME is absolute, it returns it unchanged. Otherwise, it returns #f. %search-load-path will not return matches that refer to directories. *** (primitive-load FILENAME :optional CASE-INSENSITIVE-P SHARP) uses %seach-load-path to find a file named FILENAME, and loads it if it finds it. If it can't read FILENAME for any reason, it throws an error. The arguments CASE-INSENSITIVE-P and SHARP are interpreted as by the `read' function. *** load uses the same searching semantics as primitive-load. *** The functions %try-load, try-load-with-path, %load, load-with-path, basic-try-load-with-path, basic-load-with-path, try-load-module-with- path, and load-module-with-path have been deleted. The functions above should serve their purposes. *** If the value of the variable %load-hook is a procedure, `primitive-load' applies its value to the name of the file being loaded (without the load path directory name prepended). If its value is #f, it is ignored. Otherwise, an error occurs. This is mostly useful for printing load notification messages. ** The function `eval!' is no longer accessible from the scheme level. We can't allow operations which introduce glocs into the scheme level, because Guile's type system can't handle these as data. Use `eval' or `read-and-eval!' (see below) as replacement. ** The new function read-and-eval! reads an expression from PORT, evaluates it, and returns the result. This is more efficient than simply calling `read' and `eval', since it is not necessary to make a copy of the expression for the evaluator to munge. Its optional arguments CASE_INSENSITIVE_P and SHARP are interpreted as for the `read' function. ** The function `int?' has been removed; its definition was identical to that of `integer?'. ** The functions `?', and `>=?'. Code should use the R4RS names for these functions. ** The function object-properties no longer returns the hash handle; it simply returns the object's property list. ** Many functions have been changed to throw errors, instead of returning #f on failure. The point of providing exception handling in the language is to simplify the logic of user code, but this is less useful if Guile's primitives don't throw exceptions. ** The function `fileno' has been renamed from `%fileno'. ** The function primitive-mode->fdes returns #t or #f now, not 1 or 0. * Changes to Guile's C interface: ** The library's initialization procedure has been simplified. scm_boot_guile now has the prototype: void scm_boot_guile (int ARGC, char **ARGV, void (*main_func) (), void *closure); scm_boot_guile calls MAIN_FUNC, passing it CLOSURE, ARGC, and ARGV. MAIN_FUNC should do all the work of the program (initializing other packages, reading user input, etc.) before returning. When MAIN_FUNC returns, call exit (0); this function never returns. If you want some other exit value, MAIN_FUNC may call exit itself. scm_boot_guile arranges for program-arguments to return the strings given by ARGC and ARGV. If MAIN_FUNC modifies ARGC/ARGV, should call scm_set_program_arguments with the final list, so Scheme code will know which arguments have been processed. scm_boot_guile establishes a catch-all catch handler which prints an error message and exits the process. This means that Guile exits in a coherent way when system errors occur and the user isn't prepared to handle it. If the user doesn't like this behavior, they can establish their own universal catcher in MAIN_FUNC to shadow this one. Why must the caller do all the real work from MAIN_FUNC? The garbage collector assumes that all local variables of type SCM will be above scm_boot_guile's stack frame on the stack. If you try to manipulate SCM values after this function returns, it's the luck of the draw whether the GC will be able to find the objects you allocate. So, scm_boot_guile function exits, rather than returning, to discourage people from making that mistake. The IN, OUT, and ERR arguments were removed; there are other convenient ways to override these when desired. The RESULT argument was deleted; this function should never return. The BOOT_CMD argument was deleted; the MAIN_FUNC argument is more general. ** Guile's header files should no longer conflict with your system's header files. In order to compile code which #included , previous versions of Guile required you to add a directory containing all the Guile header files to your #include path. This was a problem, since Guile's header files have names which conflict with many systems' header files. Now only need appear in your #include path; you must refer to all Guile's other header files as . Guile's installation procedure puts libguile.h in $(includedir), and the rest in $(includedir)/libguile. ** Two new C functions, scm_protect_object and scm_unprotect_object, have been added to the Guile library. scm_protect_object (OBJ) protects OBJ from the garbage collector. OBJ will not be freed, even if all other references are dropped, until someone does scm_unprotect_object (OBJ). Both functions return OBJ. Note that calls to scm_protect_object do not nest. You can call scm_protect_object any number of times on a given object, and the next call to scm_unprotect_object will unprotect it completely. Basically, scm_protect_object and scm_unprotect_object just maintain a list of references to things. Since the GC knows about this list, all objects it mentions stay alive. scm_protect_object adds its argument to the list; scm_unprotect_object remove its argument from the list. ** scm_eval_0str now returns the value of the last expression evaluated. ** The new function scm_read_0str reads an s-expression from a null-terminated string, and returns it. ** The new function `scm_stdio_to_port' converts a STDIO file pointer to a Scheme port object. ** The new function `scm_set_program_arguments' allows C code to set the value returned by the Scheme `program-arguments' function. Older changes: * Guile no longer includes sophisticated Tcl/Tk support. The old Tcl/Tk support was unsatisfying to us, because it required the user to link against the Tcl library, as well as Tk and Guile. The interface was also un-lispy, in that it preserved Tcl/Tk's practice of referring to widgets by names, rather than exporting widgets to Scheme code as a special datatype. In the Usenix Tk Developer's Workshop held in July 1996, the Tcl/Tk maintainers described some very interesting changes in progress to the Tcl/Tk internals, which would facilitate clean interfaces between lone Tk and other interpreters --- even for garbage-collected languages like Scheme. They expected the new Tk to be publicly available in the fall of 1996. Since it seems that Guile might soon have a new, cleaner interface to lone Tk, and that the old Guile/Tk glue code would probably need to be completely rewritten, we (Jim Blandy and Richard Stallman) have decided not to support the old code. We'll spend the time instead on a good interface to the newer Tk, as soon as it is available. Until then, gtcltk-lib provides trivial, low-maintenance functionality. Copyright information: Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2006 Free Software Foundation, Inc. Permission is granted to anyone to make or distribute verbatim copies of this document as received, in any medium, provided that the copyright notice and this permission notice are preserved, thus giving the recipient permission to redistribute in turn. Permission is granted to distribute modified versions of this document, or of portions of it, under the above conditions, provided also that they carry prominent notices stating who last changed them. Local variables: mode: outline paragraph-separate: "[ ]*$" end: