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diff --git a/pod/perl595delta.pod b/pod/perl595delta.pod deleted file mode 100644 index 097b6b4dc7..0000000000 --- a/pod/perl595delta.pod +++ /dev/null @@ -1,587 +0,0 @@ -=head1 NAME - -perl595delta - what is new for perl v5.9.5 - -=head1 DESCRIPTION - -This document describes differences between the 5.9.4 and the 5.9.5 -development releases. See L<perl590delta>, L<perl591delta>, -L<perl592delta>, L<perl593delta> and L<perl594delta> for the differences -between 5.8.0 and 5.9.4. - -=head1 Incompatible Changes - -=head2 Tainting and printf - -When perl is run under taint mode, C<printf()> and C<sprintf()> will now -reject any tainted format argument. (Rafael Garcia-Suarez) - -=head2 undef and signal handlers - -Undefining or deleting a signal handler via C<undef $SIG{FOO}> is now -equivalent to setting it to C<'DEFAULT'>. (Rafael) - -=head2 strictures and array/hash dereferencing in defined() - -C<defined @$foo> and C<defined %$bar> are now subject to C<strict 'refs'> -(that is, C<$foo> and C<$bar> shall be proper references there.) -(Nicholas Clark) - -(However, C<defined(@foo)> and C<defined(%bar)> are discouraged constructs -anyway.) - -=head2 C<(?p{})> has been removed - -The regular expression construct C<(?p{})>, which was deprecated in perl -5.8, has been removed. Use C<(??{})> instead. (Rafael) - -=head2 Pseudo-hashes have been removed - -Support for pseudo-hashes has been removed from Perl 5.9. (The C<fields> -pragma remains here, but uses an alternate implementation.) - -=head2 Removal of the bytecode compiler and of perlcc - -C<perlcc>, the byteloader and the supporting modules (B::C, B::CC, -B::Bytecode, etc.) are no longer distributed with the perl sources. Those -experimental tools have never worked reliably, and, due to the lack of -volunteers to keep them in line with the perl interpreter developments, it -was decided to remove them instead of shipping a broken version of those. -The last version of those modules can be found with perl 5.9.4. - -However the B compiler framework stays supported in the perl core, as with -the more useful modules it has permitted (among others, B::Deparse and -B::Concise). - -=head2 Removal of the JPL - -The JPL (Java-Perl Linguo) has been removed from the perl sources tarball. - -=head2 Recursive inheritance detected earlier - -Perl will now immediately throw an exception if you modify any package's -C<@ISA> in such a way that it would cause recursive inheritance. - -Previously, the exception would not occur until Perl attempted to make -use of the recursive inheritance while resolving a method or doing a -C<$foo-E<gt>isa($bar)> lookup. - -=head1 Core Enhancements - -=head2 Regular expressions - -=over 4 - -=item Recursive Patterns - -It is now possible to write recursive patterns without using the C<(??{})> -construct. This new way is more efficient, and in many cases easier to -read. - -Each capturing parenthesis can now be treated as an independent pattern -that can be entered by using the C<(?PARNO)> syntax (C<PARNO> standing for -"parenthesis number"). For example, the following pattern will match -nested balanced angle brackets: - - / - ^ # start of line - ( # start capture buffer 1 - < # match an opening angle bracket - (?: # match one of: - (?> # don't backtrack over the inside of this group - [^<>]+ # one or more non angle brackets - ) # end non backtracking group - | # ... or ... - (?1) # recurse to bracket 1 and try it again - )* # 0 or more times. - > # match a closing angle bracket - ) # end capture buffer one - $ # end of line - /x - -Note, users experienced with PCRE will find that the Perl implementation -of this feature differs from the PCRE one in that it is possible to -backtrack into a recursed pattern, whereas in PCRE the recursion is -atomic or "possessive" in nature. (Yves Orton) - -=item Named Capture Buffers - -It is now possible to name capturing parenthesis in a pattern and refer to -the captured contents by name. The naming syntax is C<< (?<NAME>....) >>. -It's possible to backreference to a named buffer with the C<< \k<NAME> >> -syntax. In code, the new magical hashes C<%+> and C<%-> can be used to -access the contents of the capture buffers. - -Thus, to replace all doubled chars, one could write - - s/(?<letter>.)\k<letter>/$+{letter}/g - -Only buffers with defined contents will be "visible" in the C<%+> hash, so -it's possible to do something like - - foreach my $name (keys %+) { - print "content of buffer '$name' is $+{$name}\n"; - } - -The C<%-> hash is a bit more complete, since it will contain array refs -holding values from all capture buffers similarly named, if there should -be many of them. - -C<%+> and C<%-> are implemented as tied hashes through the new module -C<Tie::Hash::NamedCapture>. - -Users exposed to the .NET regex engine will find that the perl -implementation differs in that the numerical ordering of the buffers -is sequential, and not "unnamed first, then named". Thus in the pattern - - /(A)(?<B>B)(C)(?<D>D)/ - -$1 will be 'A', $2 will be 'B', $3 will be 'C' and $4 will be 'D' and not -$1 is 'A', $2 is 'C' and $3 is 'B' and $4 is 'D' that a .NET programmer -would expect. This is considered a feature. :-) (Yves Orton) - -=item Possessive Quantifiers - -Perl now supports the "possessive quantifier" syntax of the "atomic match" -pattern. Basically a possessive quantifier matches as much as it can and never -gives any back. Thus it can be used to control backtracking. The syntax is -similar to non-greedy matching, except instead of using a '?' as the modifier -the '+' is used. Thus C<?+>, C<*+>, C<++>, C<{min,max}+> are now legal -quantifiers. (Yves Orton) - -=item Backtracking control verbs - -The regex engine now supports a number of special-purpose backtrack -control verbs: (*THEN), (*PRUNE), (*MARK), (*SKIP), (*COMMIT), (*FAIL) -and (*ACCEPT). See L<perlre> for their descriptions. (Yves Orton) - -=item Relative backreferences - -A new syntax C<\g{N}> or C<\gN> where "N" is a decimal integer allows a -safer form of back-reference notation as well as allowing relative -backreferences. This should make it easier to generate and embed patterns -that contain backreferences. See L<perlre/"Capture buffers">. (Yves Orton) - -=item C<\K> escape - -The functionality of Jeff Pinyan's module Regexp::Keep has been added to -the core. You can now use in regular expressions the special escape C<\K> -as a way to do something like floating length positive lookbehind. It is -also useful in substitutions like: - - s/(foo)bar/$1/g - -that can now be converted to - - s/foo\Kbar//g - -which is much more efficient. (Yves Orton) - -=item Vertical and horizontal whitespace, and linebreak - -Regular expressions now recognize the C<\v> and C<\h> escapes, that match -vertical and horizontal whitespace, respectively. C<\V> and C<\H> -logically match their complements. - -C<\R> matches a generic linebreak, that is, vertical whitespace, plus -the multi-character sequence C<"\x0D\x0A">. - -=back - -=head2 The C<_> prototype - -A new prototype character has been added. C<_> is equivalent to C<$> (it -denotes a scalar), but defaults to C<$_> if the corresponding argument -isn't supplied. Due to the optional nature of the argument, you can only -use it at the end of a prototype, or before a semicolon. - -This has a small incompatible consequence: the prototype() function has -been adjusted to return C<_> for some built-ins in appropriate cases (for -example, C<prototype('CORE::rmdir')>). (Rafael) - -=head2 UNITCHECK blocks - -C<UNITCHECK>, a new special code block has been introduced, in addition to -C<BEGIN>, C<CHECK>, C<INIT> and C<END>. - -C<CHECK> and C<INIT> blocks, while useful for some specialized purposes, -are always executed at the transition between the compilation and the -execution of the main program, and thus are useless whenever code is -loaded at runtime. On the other hand, C<UNITCHECK> blocks are executed -just after the unit which defined them has been compiled. See L<perlmod> -for more information. (Alex Gough) - -=head2 readpipe() is now overridable - -The built-in function readpipe() is now overridable. Overriding it permits -also to override its operator counterpart, C<qx//> (a.k.a. C<``>). -Moreover, it now defaults to C<$_> if no argument is provided. (Rafael) - -=head2 default argument for readline() - -readline() now defaults to C<*ARGV> if no argument is provided. (Rafael) - -=head2 UCD 5.0.0 - -The copy of the Unicode Character Database included in Perl 5.9 has -been updated to version 5.0.0. - -=head2 Smart match - -The smart match operator (C<~~>) is now available by default (you don't -need to enable it with C<use feature> any longer). (Michael G Schwern) - -=head2 Implicit loading of C<feature> - -The C<feature> pragma is now implicitly loaded when you require a minimal -perl version (with the C<use VERSION> construct) greater than, or equal -to, 5.9.5. - -=head1 Modules and Pragmas - -=head2 New Pragma, C<mro> - -A new pragma, C<mro> (for Method Resolution Order) has been added. It -permits to switch, on a per-class basis, the algorithm that perl uses to -find inherited methods in case of a multiple inheritance hierarchy. The -default MRO hasn't changed (DFS, for Depth First Search). Another MRO is -available: the C3 algorithm. See L<mro> for more information. -(Brandon Black) - -Note that, due to changes in the implementation of class hierarchy search, -code that used to undef the C<*ISA> glob will most probably break. Anyway, -undef'ing C<*ISA> had the side-effect of removing the magic on the @ISA -array and should not have been done in the first place. - -=head2 bignum, bigint, bigrat - -The three numeric pragmas C<bignum>, C<bigint> and C<bigrat> are now -lexically scoped. (Tels) - -=head2 Math::BigInt/Math::BigFloat - -Many bugs have been fixed; noteworthy are comparisons with NaN, which -no longer warn about undef values. - -The following things are new: - -=over 4 - -=item config() - -The config() method now also supports the calling-style -C<< config('lib') >> in addition to C<< config()->{'lib'} >>. - -=item import() - -Upon import, using C<< lib => 'Foo' >> now warns if the low-level library -cannot be found. To suppress the warning, you can use C<< try => 'Foo' >> -instead. To convert the warning into a die, use C<< only => 'Foo' >> -instead. - -=item roundmode common - -A rounding mode of C<common> is now supported. - -=back - -Also, support for the following methods has been added: - -=over 4 - -=item bpi(), bcos(), bsin(), batan(), batan2() - -=item bmuladd() - -=item bexp(), bnok() - -=item from_hex(), from_oct(), and from_bin() - -=item as_oct() - -=back - -In addition, the default math-backend (Calc (Perl) and FastCalc (XS)) now -support storing numbers in parts with 9 digits instead of 7 on Perls with -either 64bit integer or long double support. This means math operations -scale better and are thus faster for really big numbers. - -=head2 New Core Modules - -=over 4 - -=item * - -C<Locale::Maketext::Simple>, needed by CPANPLUS, is a simple wrapper around -C<Locale::Maketext::Lexicon>. Note that C<Locale::Maketext::Lexicon> isn't -included in the perl core; the behaviour of C<Locale::Maketext::Simple> -gracefully degrades when the later isn't present. - -=item * - -C<Params::Check> implements a generic input parsing/checking mechanism. It -is used by CPANPLUS. - -=item * - -C<Term::UI> simplifies the task to ask questions at a terminal prompt. - -=item * - -C<Object::Accessor> provides an interface to create per-object accessors. - -=item * - -C<Module::Pluggable> is a simple framework to create modules that accept -pluggable sub-modules. - -=item * - -C<Module::Load::Conditional> provides simple ways to query and possibly -load installed modules. - -=item * - -C<Time::Piece> provides an object oriented interface to time functions, -overriding the built-ins localtime() and gmtime(). - -=item * - -C<IPC::Cmd> helps to find and run external commands, possibly -interactively. - -=item * - -C<File::Fetch> provide a simple generic file fetching mechanism. - -=item * - -C<Log::Message> and C<Log::Message::Simple> are used by the log facility -of C<CPANPLUS>. - -=item * - -C<Archive::Extract> is a generic archive extraction mechanism -for F<.tar> (plain, gzipped or bzipped) or F<.zip> files. - -=item * - -C<CPANPLUS> provides an API and a command-line tool to access the CPAN -mirrors. - -=back - -=head2 Module changes - -=over 4 - -=item C<assertions> - -The C<assertions> pragma, its submodules C<assertions::activate> and -C<assertions::compat> and the B<-A> command-line switch have been removed. -The interface was not judged mature enough for inclusion in a stable -release. - -=item C<base> - -The C<base> pragma now warns if a class tries to inherit from itself. -(Curtis "Ovid" Poe) - -=item C<strict> and C<warnings> - -C<strict> and C<warnings> will now complain loudly if they are loaded via -incorrect casing (as in C<use Strict;>). (Johan Vromans) - -=item C<warnings> - -The C<warnings> pragma doesn't load C<Carp> anymore. That means that code -that used C<Carp> routines without having loaded it at compile time might -need to be adjusted; typically, the following (faulty) code won't work -anymore, and will require parentheses to be added after the function name: - - use warnings; - require Carp; - Carp::confess "argh"; - -=item C<less> - -C<less> now does something useful (or at least it tries to). In fact, it -has been turned into a lexical pragma. So, in your modules, you can now -test whether your users have requested to use less CPU, or less memory, -less magic, or maybe even less fat. See L<less> for more. (Joshua ben -Jore) - -=item C<Attribute::Handlers> - -C<Attribute::Handlers> can now report the caller's file and line number. -(David Feldman) - -=item C<B::Lint> - -C<B::Lint> is now based on C<Module::Pluggable>, and so can be extended -with plugins. (Joshua ben Jore) - -=item C<B> - -It's now possible to access the lexical pragma hints (C<%^H>) by using the -method B::COP::hints_hash(). It returns a C<B::RHE> object, which in turn -can be used to get a hash reference via the method B::RHE::HASH(). (Joshua -ben Jore) - -=for p5p XXX document this in B.pm too - -=item C<Thread> - -As the old 5005thread threading model has been removed, in favor of the -ithreads scheme, the C<Thread> module is now a compatibility wrapper, to -be used in old code only. It has been removed from the default list of -dynamic extensions. - -=back - -=head1 Utility Changes - -=head2 C<cpanp> - -C<cpanp>, the CPANPLUS shell, has been added. (C<cpanp-run-perl>, an -helper for CPANPLUS operation, has been added too, but isn't intended for -direct use). - -=head2 C<cpan2dist> - -C<cpan2dist> is a new utility, that comes with CPANPLUS. It's a tool to -create distributions (or packages) from CPAN modules. - -=head2 C<pod2html> - -The output of C<pod2html> has been enhanced to be more customizable via -CSS. Some formatting problems were also corrected. (Jari Aalto) - -=head1 Documentation - -=head2 New manpage, perlunifaq - -A new manual page, L<perlunifaq> (the Perl Unicode FAQ), has been added -(Juerd Waalboer). - -=head1 Installation and Configuration Improvements - -=head2 C++ compatibility - -Efforts have been made to make perl and the core XS modules compilable -with various C++ compilers (although the situation is not perfect with -some of the compilers on some of the platforms tested.) - -=head2 Visual C++ - -Perl now can be compiled with Microsoft Visual C++ 2005. - -=head2 Static build on Win32 - -It's now possible to build a C<perl-static.exe> that doesn't depend -on C<perl59.dll> on Win32. See the Win32 makefiles for details. -(Vadim Konovalov) - -=head2 win32 builds - -All win32 builds (MS-Win, WinCE) have been merged and cleaned up. - -=head2 C<d_pseudofork> and C<d_printf_format_null> - -A new configuration variable, available as C<$Config{d_pseudofork}> in -the L<Config> module, has been added, to distinguish real fork() support -from fake pseudofork used on Windows platforms. - -A new configuration variable, C<d_printf_format_null>, has been added, -to see if printf-like formats are allowed to be NULL. - -=head2 Help - -C<Configure -h> has been extended with the most used option. - -Much less 'Whoa there' messages. - -=head2 64bit systems - -Better detection of 64bit(only) systems, and setting all the (library) -paths accordingly. - -=head2 Ports - -Perl has been reported to work on MidnightBSD. - -Support for Cray XT4 Catamount/Qk has been added. - -Vendor patches have been merged for RedHat and GenToo. - -=head1 Selected Bug Fixes - -PerlIO::scalar will now prevent writing to read-only scalars. Moreover, -seek() is now supported with PerlIO::scalar-based filehandles, the -underlying string being zero-filled as needed. (Rafael, Jarkko Hietaniemi) - -study() never worked for UTF-8 strings, but could lead to false results. -It's now a no-op on UTF-8 data. (Yves Orton) - -The signals SIGILL, SIGBUS and SIGSEGV are now always delivered in an -"unsafe" manner (contrary to other signals, that are deferred until the -perl interpreter reaches a reasonably stable state; see -L<perlipc/"Deferred Signals (Safe Signals)">). (Rafael) - -When a module or a file is loaded through an @INC-hook, and when this hook -has set a filename entry in %INC, __FILE__ is now set for this module -accordingly to the contents of that %INC entry. (Rafael) - -The C<-w> and C<-t> switches can now be used together without messing -up what categories of warnings are activated or not. (Rafael) - -Duping a filehandle which has the C<:utf8> PerlIO layer set will now -properly carry that layer on the duped filehandle. (Rafael) - -Localizing an hash element whose key was given as a variable didn't work -correctly if the variable was changed while the local() was in effect (as -in C<local $h{$x}; ++$x>). (Bo Lindbergh) - -=head1 New or Changed Diagnostics - -=head2 Deprecations - -Two deprecation warnings have been added: (Rafael) - - Opening dirhandle %s also as a file - Opening filehandle %s also as a directory - -=head1 Changed Internals - -The anonymous hash and array constructors now take 1 op in the optree -instead of 3, now that pp_anonhash and pp_anonlist return a reference to -an hash/array when the op is flagged with OPf_SPECIAL (Nicholas Clark). - -=for p5p XXX have we some docs on how to create regexp engine plugins, since that's now possible ? (perlreguts) - -=for p5p XXX new BIND SV type, #29544, #29642 - -=head1 Reporting Bugs - -If you find what you think is a bug, you might check the articles -recently posted to the comp.lang.perl.misc newsgroup and the perl -bug database at http://rt.perl.org/rt3/ . There may also be -information at http://www.perl.org/ , the Perl Home Page. - -If you believe you have an unreported bug, please run the B<perlbug> -program included with your release. Be sure to trim your bug down -to a tiny but sufficient test case. Your bug report, along with the -output of C<perl -V>, will be sent off to perlbug@perl.org to be -analysed by the Perl porting team. - -=head1 SEE ALSO - -The F<Changes> file for exhaustive details on what changed. - -The F<INSTALL> file for how to build Perl. - -The F<README> file for general stuff. - -The F<Artistic> and F<Copying> files for copyright information. - -=cut |