/* Copyright (C) 1995,1996,1997,1998,1999,2000,2001 Free Software Foundation, Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this software; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307 USA * * As a special exception, the Free Software Foundation gives permission * for additional uses of the text contained in its release of GUILE. * * The exception is that, if you link the GUILE library with other files * to produce an executable, this does not by itself cause the * resulting executable to be covered by the GNU General Public License. * Your use of that executable is in no way restricted on account of * linking the GUILE library code into it. * * This exception does not however invalidate any other reasons why * the executable file might be covered by the GNU General Public License. * * This exception applies only to the code released by the * Free Software Foundation under the name GUILE. If you copy * code from other Free Software Foundation releases into a copy of * GUILE, as the General Public License permits, the exception does * not apply to the code that you add in this way. To avoid misleading * anyone as to the status of such modified files, you must delete * this exception notice from them. * * If you write modifications of your own for GUILE, it is your choice * whether to permit this exception to apply to your modifications. * If you do not wish that, delete this exception notice. */ /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999, gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */ /* This file is read twice in order to produce debugging versions of * scm_ceval and scm_apply. These functions, scm_deval and * scm_dapply, are produced when we define the preprocessor macro * DEVAL. The file is divided into sections which are treated * differently with respect to DEVAL. The heads of these sections are * marked with the string "SECTION:". */ /* SECTION: This code is compiled once. */ #ifndef DEVAL /* We need this to get the definitions for HAVE_ALLOCA_H, etc. */ #include "libguile/scmconfig.h" /* AIX requires this to be the first thing in the file. The #pragma directive is indented so pre-ANSI compilers will ignore it, rather than choke on it. */ #ifndef __GNUC__ # if HAVE_ALLOCA_H # include # else # ifdef _AIX #pragma alloca # else # ifndef alloca /* predefined by HP cc +Olibcalls */ char *alloca (); # endif # endif # endif #endif #include "libguile/_scm.h" #include "libguile/debug.h" #include "libguile/dynwind.h" #include "libguile/alist.h" #include "libguile/eq.h" #include "libguile/continuations.h" #include "libguile/throw.h" #include "libguile/smob.h" #include "libguile/macros.h" #include "libguile/procprop.h" #include "libguile/hashtab.h" #include "libguile/hash.h" #include "libguile/srcprop.h" #include "libguile/stackchk.h" #include "libguile/objects.h" #include "libguile/async.h" #include "libguile/feature.h" #include "libguile/modules.h" #include "libguile/ports.h" #include "libguile/root.h" #include "libguile/vectors.h" #include "libguile/fluids.h" #include "libguile/values.h" #include "libguile/validate.h" #include "libguile/eval.h" #define SCM_VALIDATE_NON_EMPTY_COMBINATION(x) \ do { \ if (SCM_EQ_P ((x), SCM_EOL)) \ scm_misc_error (NULL, scm_s_expression, SCM_EOL); \ } while (0) /* The evaluator contains a plethora of EVAL symbols. * This is an attempt at explanation. * * The following macros should be used in code which is read twice * (where the choice of evaluator is hard soldered): * * SCM_CEVAL is the symbol used within one evaluator to call itself. * Originally, it is defined to scm_ceval, but is redefined to * scm_deval during the second pass. * * SIDEVAL corresponds to SCM_CEVAL, but is used in situations where * only side effects of expressions matter. All immediates are * ignored. * * SCM_EVALIM is used when it is known that the expression is an * immediate. (This macro never calls an evaluator.) * * EVALCAR evaluates the car of an expression. * * EVALCELLCAR is like EVALCAR, but is used when it is known that the * car is a lisp cell. * * The following macros should be used in code which is read once * (where the choice of evaluator is dynamic): * * SCM_XEVAL takes care of immediates without calling an evaluator. It * then calls scm_ceval *or* scm_deval, depending on the debugging * mode. * * SCM_XEVALCAR corresponds to EVALCAR, but uses scm_ceval *or* scm_deval * depending on the debugging mode. * * The main motivation for keeping this plethora is efficiency * together with maintainability (=> locality of code). */ #define SCM_CEVAL scm_ceval #define SIDEVAL(x, env) if (SCM_NIMP (x)) SCM_CEVAL((x), (env)) #define EVALCELLCAR(x, env) (SCM_SYMBOLP (SCM_CAR (x)) \ ? *scm_lookupcar (x, env, 1) \ : SCM_CEVAL (SCM_CAR (x), env)) #define EVALCAR(x, env) (!SCM_CELLP (SCM_CAR (x)) \ ? (SCM_IMP (SCM_CAR (x)) \ ? SCM_EVALIM (SCM_CAR (x), env) \ : SCM_GLOC_VAL (SCM_CAR (x))) \ : EVALCELLCAR (x, env)) #define EXTEND_ENV SCM_EXTEND_ENV #ifdef MEMOIZE_LOCALS SCM * scm_ilookup (SCM iloc, SCM env) { register long ir = SCM_IFRAME (iloc); register SCM er = env; for (; 0 != ir; --ir) er = SCM_CDR (er); er = SCM_CAR (er); for (ir = SCM_IDIST (iloc); 0 != ir; --ir) er = SCM_CDR (er); if (SCM_ICDRP (iloc)) return SCM_CDRLOC (er); return SCM_CARLOC (SCM_CDR (er)); } #endif #ifdef USE_THREADS /* The Lookup Car Race - by Eva Luator Memoization of variables and special forms is done while executing the code for the first time. As long as there is only one thread everything is fine, but as soon as two threads execute the same code concurrently `for the first time' they can come into conflict. This memoization includes rewriting variable references into more efficient forms and expanding macros. Furthermore, macro expansion includes `compiling' special forms like `let', `cond', etc. into tree-code instructions. There shouldn't normally be a problem with memoizing local and global variable references (into ilocs and glocs), because all threads will mutate the code in *exactly* the same way and (if I read the C code correctly) it is not possible to observe a half-way mutated cons cell. The lookup procedure can handle this transparently without any critical sections. It is different with macro expansion, because macro expansion happens outside of the lookup procedure and can't be undone. Therefore it can't cope with it. It has to indicate failure when it detects a lost race and hope that the caller can handle it. Luckily, it turns out that this is the case. An example to illustrate this: Suppose that the follwing form will be memoized concurrently by two threads (let ((x 12)) x) Let's first examine the lookup of X in the body. The first thread decides that it has to find the symbol "x" in the environment and starts to scan it. Then the other thread takes over and actually overtakes the first. It looks up "x" and substitutes an appropriate iloc for it. Now the first thread continues and completes its lookup. It comes to exactly the same conclusions as the second one and could - without much ado - just overwrite the iloc with the same iloc. But let's see what will happen when the race occurs while looking up the symbol "let" at the start of the form. It could happen that the second thread interrupts the lookup of the first thread and not only substitutes a gloc for it but goes right ahead and replaces it with the compiled form (#@let* (x 12) x). Now, when the first thread completes its lookup, it would replace the #@let* with a gloc pointing to the "let" binding, effectively reverting the form to (let (x 12) x). This is wrong. It has to detect that it has lost the race and the evaluator has to reconsider the changed form completely. This race condition could be resolved with some kind of traffic light (like mutexes) around scm_lookupcar, but I think that it is best to avoid them in this case. They would serialize memoization completely and because lookup involves calling arbitrary Scheme code (via the lookup-thunk), threads could be blocked for an arbitrary amount of time or even deadlock. But with the current solution a lot of unnecessary work is potentially done. */ /* SCM_LOOKUPCAR1 is was SCM_LOOKUPCAR used to be but is allowed to return NULL to indicate a failed lookup due to some race conditions between threads. This only happens when VLOC is the first cell of a special form that will eventually be memoized (like `let', etc.) In that case the whole lookup is bogus and the caller has to reconsider the complete special form. SCM_LOOKUPCAR is still there, of course. It just calls SCM_LOOKUPCAR1 and aborts on recieving NULL. So SCM_LOOKUPCAR should only be called when it is known that VLOC is not the first pair of a special form. Otherwise, use SCM_LOOKUPCAR1 and check for NULL. I think I've found the only places where this applies. */ #endif /* USE_THREADS */ SCM_SYMBOL (scm_unbound_variable_key, "unbound-variable"); #ifdef USE_THREADS static SCM * scm_lookupcar1 (SCM vloc, SCM genv, int check) #else SCM * scm_lookupcar (SCM vloc, SCM genv, int check) #endif { SCM env = genv; register SCM *al, fl, var = SCM_CAR (vloc); #ifdef MEMOIZE_LOCALS register SCM iloc = SCM_ILOC00; #endif for (; SCM_NIMP (env); env = SCM_CDR (env)) { if (!SCM_CONSP (SCM_CAR (env))) break; al = SCM_CARLOC (env); for (fl = SCM_CAR (*al); SCM_NIMP (fl); fl = SCM_CDR (fl)) { if (SCM_NCONSP (fl)) { if (SCM_EQ_P (fl, var)) { #ifdef MEMOIZE_LOCALS #ifdef USE_THREADS if (! SCM_EQ_P (SCM_CAR (vloc), var)) goto race; #endif SCM_SET_CELL_WORD_0 (vloc, SCM_UNPACK (iloc) + SCM_ICDR); #endif return SCM_CDRLOC (*al); } else break; } al = SCM_CDRLOC (*al); if (SCM_EQ_P (SCM_CAR (fl), var)) { #ifdef MEMOIZE_LOCALS #ifndef SCM_RECKLESS /* letrec inits to SCM_UNDEFINED */ if (SCM_UNBNDP (SCM_CAR (*al))) { env = SCM_EOL; goto errout; } #endif #ifdef USE_THREADS if (!SCM_EQ_P (SCM_CAR (vloc), var)) goto race; #endif SCM_SETCAR (vloc, iloc); #endif return SCM_CARLOC (*al); } #ifdef MEMOIZE_LOCALS iloc = SCM_PACK (SCM_UNPACK (iloc) + SCM_IDINC); #endif } #ifdef MEMOIZE_LOCALS iloc = SCM_PACK ((~SCM_IDSTMSK) & (SCM_UNPACK(iloc) + SCM_IFRINC)); #endif } { SCM top_thunk, real_var; if (SCM_NIMP (env)) { top_thunk = SCM_CAR (env); /* env now refers to a top level env thunk */ env = SCM_CDR (env); } else top_thunk = SCM_BOOL_F; real_var = scm_sym2var (var, top_thunk, SCM_BOOL_F); if (SCM_FALSEP (real_var)) goto errout; #ifndef SCM_RECKLESS if (SCM_NNULLP (env) || SCM_UNBNDP (SCM_VARIABLE_REF (real_var))) { errout: /* scm_everr (vloc, genv,...) */ if (check) { if (SCM_NULLP (env)) scm_error (scm_unbound_variable_key, NULL, "Unbound variable: ~S", scm_cons (var, SCM_EOL), SCM_BOOL_F); else scm_misc_error (NULL, "Damaged environment: ~S", scm_cons (var, SCM_EOL)); } else { /* A variable could not be found, but we shall not throw an error. */ static SCM undef_object = SCM_UNDEFINED; return &undef_object; } } #endif #ifdef USE_THREADS if (!SCM_EQ_P (SCM_CAR (vloc), var)) { /* Some other thread has changed the very cell we are working on. In effect, it must have done our job or messed it up completely. */ race: var = SCM_CAR (vloc); if (SCM_ITAG3 (var) == scm_tc3_cons_gloc) return SCM_GLOC_VAL_LOC (var); #ifdef MEMOIZE_LOCALS if (SCM_ITAG7 (var) == SCM_ITAG7 (SCM_ILOC00)) return scm_ilookup (var, genv); #endif /* We can't cope with anything else than glocs and ilocs. When a special form has been memoized (i.e. `let' into `#@let') we return NULL and expect the calling function to do the right thing. For the evaluator, this means going back and redoing the dispatch on the car of the form. */ return NULL; } #endif /* USE_THREADS */ SCM_SET_CELL_WORD_0 (vloc, SCM_UNPACK (real_var) + scm_tc3_cons_gloc); return SCM_VARIABLE_LOC (real_var); } } #ifdef USE_THREADS SCM * scm_lookupcar (SCM vloc, SCM genv, int check) { SCM *loc = scm_lookupcar1 (vloc, genv, check); if (loc == NULL) abort (); return loc; } #endif #define unmemocar scm_unmemocar SCM_SYMBOL (sym_three_question_marks, "???"); SCM scm_unmemocar (SCM form, SCM env) { SCM c; if (SCM_IMP (form)) return form; c = SCM_CAR (form); if (SCM_ITAG3 (c) == scm_tc3_cons_gloc) { SCM sym = scm_module_reverse_lookup (scm_env_module (env), SCM_GLOC_VAR (c)); if (SCM_EQ_P (sym, SCM_BOOL_F)) sym = sym_three_question_marks; SCM_SETCAR (form, sym); } #ifdef MEMOIZE_LOCALS #ifdef DEBUG_EXTENSIONS else if (SCM_ILOCP (c)) { long ir; for (ir = SCM_IFRAME (c); ir != 0; --ir) env = SCM_CDR (env); env = SCM_CAR (SCM_CAR (env)); for (ir = SCM_IDIST (c); ir != 0; --ir) env = SCM_CDR (env); SCM_SETCAR (form, SCM_ICDRP (c) ? env : SCM_CAR (env)); } #endif #endif return form; } SCM scm_eval_car (SCM pair, SCM env) { return SCM_XEVALCAR (pair, env); } /* * The following rewrite expressions and * some memoized forms have different syntax */ const char scm_s_expression[] = "missing or extra expression"; const char scm_s_test[] = "bad test"; const char scm_s_body[] = "bad body"; const char scm_s_bindings[] = "bad bindings"; const char scm_s_duplicate_bindings[] = "duplicate bindings"; const char scm_s_variable[] = "bad variable"; const char scm_s_clauses[] = "bad or missing clauses"; const char scm_s_formals[] = "bad formals"; const char scm_s_duplicate_formals[] = "duplicate formals"; SCM_GLOBAL_SYMBOL (scm_sym_dot, "."); SCM_GLOBAL_SYMBOL (scm_sym_arrow, "=>"); SCM_GLOBAL_SYMBOL (scm_sym_else, "else"); SCM_GLOBAL_SYMBOL (scm_sym_unquote, "unquote"); SCM_GLOBAL_SYMBOL (scm_sym_uq_splicing, "unquote-splicing"); SCM scm_f_apply; #ifdef DEBUG_EXTENSIONS SCM_GLOBAL_SYMBOL (scm_sym_enter_frame, "enter-frame"); SCM_GLOBAL_SYMBOL (scm_sym_apply_frame, "apply-frame"); SCM_GLOBAL_SYMBOL (scm_sym_exit_frame, "exit-frame"); SCM_GLOBAL_SYMBOL (scm_sym_trace, "trace"); #endif /* Check that the body denoted by XORIG is valid and rewrite it into its internal form. The internal form of a body is just the body itself, but prefixed with an ISYM that denotes to what kind of outer construct this body belongs. A lambda body starts with SCM_IM_LAMBDA, for example, a body of a let starts with SCM_IM_LET, etc. The one exception is a body that belongs to a letrec that has been formed by rewriting internal defines: it starts with SCM_IM_DEFINE. */ /* XXX - Besides controlling the rewriting of internal defines, the additional ISYM could be used for improved error messages. This is not done yet. */ static SCM scm_m_body (SCM op, SCM xorig, const char *what) { SCM_ASSYNT (scm_ilength (xorig) >= 1, scm_s_expression, what); /* Don't add another ISYM if one is present already. */ if (SCM_ISYMP (SCM_CAR (xorig))) return xorig; /* Retain possible doc string. */ if (!SCM_CONSP (SCM_CAR (xorig))) { if (SCM_NNULLP (SCM_CDR(xorig))) return scm_cons (SCM_CAR (xorig), scm_m_body (op, SCM_CDR(xorig), what)); return xorig; } return scm_cons (op, xorig); } SCM_SYNTAX(s_quote,"quote", scm_makmmacro, scm_m_quote); SCM_GLOBAL_SYMBOL(scm_sym_quote, s_quote); SCM scm_m_quote (SCM xorig, SCM env SCM_UNUSED) { SCM x = scm_copy_tree (SCM_CDR (xorig)); SCM_ASSYNT (scm_ilength (SCM_CDR (xorig)) == 1, scm_s_expression, s_quote); return scm_cons (SCM_IM_QUOTE, x); } SCM_SYNTAX(s_begin, "begin", scm_makmmacro, scm_m_begin); SCM_GLOBAL_SYMBOL(scm_sym_begin, s_begin); SCM scm_m_begin (SCM xorig, SCM env SCM_UNUSED) { SCM_ASSYNT (scm_ilength (SCM_CDR (xorig)) >= 1, scm_s_expression, s_begin); return scm_cons (SCM_IM_BEGIN, SCM_CDR (xorig)); } SCM_SYNTAX(s_if, "if", scm_makmmacro, scm_m_if); SCM_GLOBAL_SYMBOL(scm_sym_if, s_if); SCM scm_m_if (SCM xorig, SCM env SCM_UNUSED) { long len = scm_ilength (SCM_CDR (xorig)); SCM_ASSYNT (len >= 2 && len <= 3, scm_s_expression, "if"); return scm_cons (SCM_IM_IF, SCM_CDR (xorig)); } /* Will go into the RnRS module when Guile is factorized. SCM_SYNTAX(scm_s_set_x,"set!", scm_makmmacro, scm_m_set_x); */ const char scm_s_set_x[] = "set!"; SCM_GLOBAL_SYMBOL(scm_sym_set_x, scm_s_set_x); SCM scm_m_set_x (SCM xorig, SCM env SCM_UNUSED) { SCM x = SCM_CDR (xorig); SCM_ASSYNT (2 == scm_ilength (x), scm_s_expression, scm_s_set_x); SCM_ASSYNT (SCM_SYMBOLP (SCM_CAR (x)), scm_s_variable, scm_s_set_x); return scm_cons (SCM_IM_SET_X, x); } SCM_SYNTAX(s_and, "and", scm_makmmacro, scm_m_and); SCM_GLOBAL_SYMBOL(scm_sym_and, s_and); SCM scm_m_and (SCM xorig, SCM env SCM_UNUSED) { long len = scm_ilength (SCM_CDR (xorig)); SCM_ASSYNT (len >= 0, scm_s_test, s_and); if (len >= 1) return scm_cons (SCM_IM_AND, SCM_CDR (xorig)); else return SCM_BOOL_T; } SCM_SYNTAX(s_or,"or", scm_makmmacro, scm_m_or); SCM_GLOBAL_SYMBOL(scm_sym_or,s_or); SCM scm_m_or (SCM xorig, SCM env SCM_UNUSED) { long len = scm_ilength (SCM_CDR (xorig)); SCM_ASSYNT (len >= 0, scm_s_test, s_or); if (len >= 1) return scm_cons (SCM_IM_OR, SCM_CDR (xorig)); else return SCM_BOOL_F; } SCM_SYNTAX(s_case, "case", scm_makmmacro, scm_m_case); SCM_GLOBAL_SYMBOL(scm_sym_case, s_case); SCM scm_m_case (SCM xorig, SCM env SCM_UNUSED) { SCM proc, cdrx = scm_list_copy (SCM_CDR (xorig)), x = cdrx; SCM_ASSYNT (scm_ilength (x) >= 2, scm_s_clauses, s_case); while (SCM_NIMP (x = SCM_CDR (x))) { proc = SCM_CAR (x); SCM_ASSYNT (scm_ilength (proc) >= 2, scm_s_clauses, s_case); SCM_ASSYNT (scm_ilength (SCM_CAR (proc)) >= 0 || (SCM_EQ_P (scm_sym_else, SCM_CAR (proc)) && SCM_NULLP (SCM_CDR (x))), scm_s_clauses, s_case); } return scm_cons (SCM_IM_CASE, cdrx); } SCM_SYNTAX(s_cond, "cond", scm_makmmacro, scm_m_cond); SCM_GLOBAL_SYMBOL(scm_sym_cond, s_cond); SCM scm_m_cond (SCM xorig, SCM env SCM_UNUSED) { SCM arg1, cdrx = scm_list_copy (SCM_CDR (xorig)), x = cdrx; long len = scm_ilength (x); SCM_ASSYNT (len >= 1, scm_s_clauses, s_cond); while (SCM_NIMP (x)) { arg1 = SCM_CAR (x); len = scm_ilength (arg1); SCM_ASSYNT (len >= 1, scm_s_clauses, s_cond); if (SCM_EQ_P (scm_sym_else, SCM_CAR (arg1))) { SCM_ASSYNT (SCM_NULLP (SCM_CDR (x)) && len >= 2, "bad ELSE clause", s_cond); SCM_SETCAR (arg1, SCM_BOOL_T); } if (len >= 2 && SCM_EQ_P (scm_sym_arrow, SCM_CAR (SCM_CDR (arg1)))) SCM_ASSYNT (3 == len && SCM_NIMP (SCM_CAR (SCM_CDR (SCM_CDR (arg1)))), "bad recipient", s_cond); x = SCM_CDR (x); } return scm_cons (SCM_IM_COND, cdrx); } SCM_SYNTAX(s_lambda, "lambda", scm_makmmacro, scm_m_lambda); SCM_GLOBAL_SYMBOL(scm_sym_lambda, s_lambda); /* Return true if OBJ is `eq?' to one of the elements of LIST or to the cdr of the last cons. (Thus, LIST is not required to be a proper list and when OBJ also found in the improper ending.) */ static int scm_c_improper_memq (SCM obj, SCM list) { for (; SCM_CONSP (list); list = SCM_CDR (list)) { if (SCM_EQ_P (SCM_CAR (list), obj)) return 1; } return SCM_EQ_P (list, obj); } SCM scm_m_lambda (SCM xorig, SCM env SCM_UNUSED) { SCM proc, x = SCM_CDR (xorig); if (scm_ilength (x) < 2) goto badforms; proc = SCM_CAR (x); if (SCM_NULLP (proc)) goto memlambda; if (SCM_EQ_P (SCM_IM_LET, proc)) /* named let */ goto memlambda; if (SCM_IMP (proc)) goto badforms; if (SCM_SYMBOLP (proc)) goto memlambda; if (SCM_NCONSP (proc)) goto badforms; while (SCM_NIMP (proc)) { if (SCM_NCONSP (proc)) { if (!SCM_SYMBOLP (proc)) goto badforms; else goto memlambda; } if (!SCM_SYMBOLP (SCM_CAR (proc))) goto badforms; else if (scm_c_improper_memq (SCM_CAR(proc), SCM_CDR(proc))) scm_misc_error (s_lambda, scm_s_duplicate_formals, SCM_EOL); proc = SCM_CDR (proc); } if (SCM_NNULLP (proc)) { badforms: scm_misc_error (s_lambda, scm_s_formals, SCM_EOL); } memlambda: return scm_cons2 (SCM_IM_LAMBDA, SCM_CAR (x), scm_m_body (SCM_IM_LAMBDA, SCM_CDR (x), s_lambda)); } SCM_SYNTAX(s_letstar,"let*", scm_makmmacro, scm_m_letstar); SCM_GLOBAL_SYMBOL(scm_sym_letstar,s_letstar); SCM scm_m_letstar (SCM xorig, SCM env SCM_UNUSED) { SCM x = SCM_CDR (xorig), arg1, proc, vars = SCM_EOL, *varloc = &vars; long len = scm_ilength (x); SCM_ASSYNT (len >= 2, scm_s_body, s_letstar); proc = SCM_CAR (x); SCM_ASSYNT (scm_ilength (proc) >= 0, scm_s_bindings, s_letstar); while (SCM_NIMP (proc)) { arg1 = SCM_CAR (proc); SCM_ASSYNT (2 == scm_ilength (arg1), scm_s_bindings, s_letstar); SCM_ASSYNT (SCM_SYMBOLP (SCM_CAR (arg1)), scm_s_variable, s_letstar); *varloc = scm_cons2 (SCM_CAR (arg1), SCM_CAR (SCM_CDR (arg1)), SCM_EOL); varloc = SCM_CDRLOC (SCM_CDR (*varloc)); proc = SCM_CDR (proc); } x = scm_cons (vars, SCM_CDR (x)); return scm_cons2 (SCM_IM_LETSTAR, SCM_CAR (x), scm_m_body (SCM_IM_LETSTAR, SCM_CDR (x), s_letstar)); } /* DO gets the most radically altered syntax (do (( ) ( ) ... ) ( ) ) ;; becomes (do_mem (varn ... var2 var1) ( ... ) ( ) () ... ) ;; missing steps replaced by var */ SCM_SYNTAX(s_do, "do", scm_makmmacro, scm_m_do); SCM_GLOBAL_SYMBOL(scm_sym_do, s_do); SCM scm_m_do (SCM xorig, SCM env SCM_UNUSED) { SCM x = SCM_CDR (xorig), arg1, proc; SCM vars = SCM_EOL, inits = SCM_EOL, steps = SCM_EOL; SCM *initloc = &inits, *steploc = &steps; long len = scm_ilength (x); SCM_ASSYNT (len >= 2, scm_s_test, "do"); proc = SCM_CAR (x); SCM_ASSYNT (scm_ilength (proc) >= 0, scm_s_bindings, "do"); while (SCM_NIMP(proc)) { arg1 = SCM_CAR (proc); len = scm_ilength (arg1); SCM_ASSYNT (2 == len || 3 == len, scm_s_bindings, "do"); SCM_ASSYNT (SCM_SYMBOLP (SCM_CAR (arg1)), scm_s_variable, "do"); /* vars reversed here, inits and steps reversed at evaluation */ vars = scm_cons (SCM_CAR (arg1), vars); /* variable */ arg1 = SCM_CDR (arg1); *initloc = scm_cons (SCM_CAR (arg1), SCM_EOL); /* init */ initloc = SCM_CDRLOC (*initloc); arg1 = SCM_CDR (arg1); *steploc = scm_cons (SCM_IMP (arg1) ? SCM_CAR (vars) : SCM_CAR (arg1), SCM_EOL); /* step */ steploc = SCM_CDRLOC (*steploc); proc = SCM_CDR (proc); } x = SCM_CDR (x); SCM_ASSYNT (scm_ilength (SCM_CAR (x)) >= 1, scm_s_test, "do"); x = scm_cons2 (SCM_CAR (x), SCM_CDR (x), steps); x = scm_cons2 (vars, inits, x); return scm_cons (SCM_IM_DO, x); } /* evalcar is small version of inline EVALCAR when we don't care about * speed */ #define evalcar scm_eval_car static SCM iqq (SCM form, SCM env, long depth); SCM_SYNTAX(s_quasiquote, "quasiquote", scm_makacro, scm_m_quasiquote); SCM_GLOBAL_SYMBOL(scm_sym_quasiquote, s_quasiquote); SCM scm_m_quasiquote (SCM xorig, SCM env) { SCM x = SCM_CDR (xorig); SCM_ASSYNT (scm_ilength (x) == 1, scm_s_expression, s_quasiquote); return iqq (SCM_CAR (x), env, 1); } static SCM iqq (SCM form, SCM env, long depth) { SCM tmp; long edepth = depth; if (SCM_IMP (form)) return form; if (SCM_VECTORP (form)) { long i = SCM_VECTOR_LENGTH (form); SCM *data = SCM_VELTS (form); tmp = SCM_EOL; for (; --i >= 0;) tmp = scm_cons (data[i], tmp); return scm_vector (iqq (tmp, env, depth)); } if (!SCM_CONSP (form)) return form; tmp = SCM_CAR (form); if (SCM_EQ_P (scm_sym_quasiquote, tmp)) { depth++; goto label; } if (SCM_EQ_P (scm_sym_unquote, tmp)) { --depth; label: form = SCM_CDR (form); SCM_ASSERT (SCM_ECONSP (form) && SCM_NULLP (SCM_CDR (form)), form, SCM_ARG1, s_quasiquote); if (0 == depth) return evalcar (form, env); return scm_cons2 (tmp, iqq (SCM_CAR (form), env, depth), SCM_EOL); } if (SCM_CONSP (tmp) && (SCM_EQ_P (scm_sym_uq_splicing, SCM_CAR (tmp)))) { tmp = SCM_CDR (tmp); if (0 == --edepth) return scm_append (scm_cons2 (evalcar (tmp, env), iqq (SCM_CDR (form), env, depth), SCM_EOL)); } return scm_cons (iqq (SCM_CAR (form), env, edepth), iqq (SCM_CDR (form), env, depth)); } /* Here are acros which return values rather than code. */ SCM_SYNTAX (s_delay, "delay", scm_makmmacro, scm_m_delay); SCM_GLOBAL_SYMBOL (scm_sym_delay, s_delay); SCM scm_m_delay (SCM xorig, SCM env SCM_UNUSED) { SCM_ASSYNT (scm_ilength (xorig) == 2, scm_s_expression, s_delay); return scm_cons2 (SCM_IM_DELAY, SCM_EOL, SCM_CDR (xorig)); } SCM_SYNTAX(s_define, "define", scm_makmmacro, scm_m_define); SCM_GLOBAL_SYMBOL(scm_sym_define, s_define); SCM scm_m_define (SCM x, SCM env) { SCM proc, arg1 = x; x = SCM_CDR (x); SCM_ASSYNT (scm_ilength (x) >= 2, scm_s_expression, s_define); proc = SCM_CAR (x); x = SCM_CDR (x); while (SCM_CONSP (proc)) { /* nested define syntax */ x = scm_cons (scm_cons2 (scm_sym_lambda, SCM_CDR (proc), x), SCM_EOL); proc = SCM_CAR (proc); } SCM_ASSYNT (SCM_SYMBOLP (proc), scm_s_variable, s_define); SCM_ASSYNT (1 == scm_ilength (x), scm_s_expression, s_define); if (SCM_TOP_LEVEL (env)) { x = evalcar (x, env); #ifdef DEBUG_EXTENSIONS if (SCM_REC_PROCNAMES_P && SCM_NIMP (x)) { arg1 = x; proc: if (SCM_CLOSUREP (arg1) /* Only the first definition determines the name. */ && SCM_FALSEP (scm_procedure_property (arg1, scm_sym_name))) scm_set_procedure_property_x (arg1, scm_sym_name, proc); else if (SCM_MACROP (arg1) /* Dirk::FIXME: Does the following test make sense? */ && !SCM_EQ_P (SCM_MACRO_CODE (arg1), arg1)) { arg1 = SCM_MACRO_CODE (arg1); goto proc; } } #endif arg1 = scm_sym2var (proc, scm_env_top_level (env), SCM_BOOL_T); SCM_VARIABLE_SET (arg1, x); #ifdef SICP return scm_cons2 (scm_sym_quote, proc, SCM_EOL); #else return SCM_UNSPECIFIED; #endif } return scm_cons2 (SCM_IM_DEFINE, proc, x); } /* end of acros */ static SCM scm_m_letrec1 (SCM op, SCM imm, SCM xorig, SCM env SCM_UNUSED) { SCM cdrx = SCM_CDR (xorig); /* locally mutable version of form */ char *what = SCM_SYMBOL_CHARS (SCM_CAR (xorig)); SCM x = cdrx, proc, arg1; /* structure traversers */ SCM vars = SCM_EOL, inits = SCM_EOL, *initloc = &inits; proc = SCM_CAR (x); SCM_ASSYNT (scm_ilength (proc) >= 1, scm_s_bindings, what); do { /* vars scm_list reversed here, inits reversed at evaluation */ arg1 = SCM_CAR (proc); SCM_ASSYNT (2 == scm_ilength (arg1), scm_s_bindings, what); SCM_ASSYNT (SCM_SYMBOLP (SCM_CAR (arg1)), scm_s_variable, what); if (scm_c_improper_memq (SCM_CAR (arg1), vars)) scm_misc_error (what, scm_s_duplicate_bindings, SCM_EOL); vars = scm_cons (SCM_CAR (arg1), vars); *initloc = scm_cons (SCM_CAR (SCM_CDR (arg1)), SCM_EOL); initloc = SCM_CDRLOC (*initloc); } while (SCM_NIMP (proc = SCM_CDR (proc))); return scm_cons2 (op, vars, scm_cons (inits, scm_m_body (imm, SCM_CDR (x), what))); } SCM_SYNTAX(s_letrec, "letrec", scm_makmmacro, scm_m_letrec); SCM_GLOBAL_SYMBOL(scm_sym_letrec, s_letrec); SCM scm_m_letrec (SCM xorig, SCM env) { SCM x = SCM_CDR (xorig); SCM_ASSYNT (scm_ilength (x) >= 2, scm_s_body, s_letrec); if (SCM_NULLP (SCM_CAR (x))) /* null binding, let* faster */ return scm_m_letstar (scm_cons2 (SCM_CAR (xorig), SCM_EOL, scm_m_body (SCM_IM_LETREC, SCM_CDR (x), s_letrec)), env); else return scm_m_letrec1 (SCM_IM_LETREC, SCM_IM_LETREC, xorig, env); } SCM_SYNTAX(s_let, "let", scm_makmmacro, scm_m_let); SCM_GLOBAL_SYMBOL(scm_sym_let, s_let); SCM scm_m_let (SCM xorig, SCM env) { SCM cdrx = SCM_CDR (xorig); /* locally mutable version of form */ SCM x = cdrx, proc, arg1, name; /* structure traversers */ SCM vars = SCM_EOL, inits = SCM_EOL, *varloc = &vars, *initloc = &inits; SCM_ASSYNT (scm_ilength (x) >= 2, scm_s_body, s_let); proc = SCM_CAR (x); if (SCM_NULLP (proc) || (SCM_CONSP (proc) && SCM_CONSP (SCM_CAR (proc)) && SCM_NULLP (SCM_CDR (proc)))) { /* null or single binding, let* is faster */ return scm_m_letstar (scm_cons2 (SCM_CAR (xorig), proc, scm_m_body (SCM_IM_LET, SCM_CDR (x), s_let)), env); } SCM_ASSYNT (SCM_NIMP (proc), scm_s_bindings, s_let); if (SCM_CONSP (proc)) { /* plain let, proc is */ return scm_m_letrec1 (SCM_IM_LET, SCM_IM_LET, xorig, env); } if (!SCM_SYMBOLP (proc)) scm_misc_error (s_let, scm_s_bindings, SCM_EOL); /* bad let */ name = proc; /* named let, build equiv letrec */ x = SCM_CDR (x); SCM_ASSYNT (scm_ilength (x) >= 2, scm_s_body, s_let); proc = SCM_CAR (x); /* bindings list */ SCM_ASSYNT (scm_ilength (proc) >= 0, scm_s_bindings, s_let); while (SCM_NIMP (proc)) { /* vars and inits both in order */ arg1 = SCM_CAR (proc); SCM_ASSYNT (2 == scm_ilength (arg1), scm_s_bindings, s_let); SCM_ASSYNT (SCM_SYMBOLP (SCM_CAR (arg1)), scm_s_variable, s_let); *varloc = scm_cons (SCM_CAR (arg1), SCM_EOL); varloc = SCM_CDRLOC (*varloc); *initloc = scm_cons (SCM_CAR (SCM_CDR (arg1)), SCM_EOL); initloc = SCM_CDRLOC (*initloc); proc = SCM_CDR (proc); } proc = scm_cons2 (scm_sym_lambda, vars, scm_m_body (SCM_IM_LET, SCM_CDR (x), "let")); proc = scm_cons2 (scm_sym_let, scm_cons (scm_cons2 (name, proc, SCM_EOL), SCM_EOL), scm_acons (name, inits, SCM_EOL)); return scm_m_letrec1 (SCM_IM_LETREC, SCM_IM_LET, proc, env); } SCM_SYNTAX (s_atapply,"@apply", scm_makmmacro, scm_m_apply); SCM_GLOBAL_SYMBOL (scm_sym_atapply, s_atapply); SCM_GLOBAL_SYMBOL (scm_sym_apply, s_atapply + 1); SCM scm_m_apply (SCM xorig, SCM env SCM_UNUSED) { SCM_ASSYNT (scm_ilength (SCM_CDR (xorig)) == 2, scm_s_expression, s_atapply); return scm_cons (SCM_IM_APPLY, SCM_CDR (xorig)); } SCM_SYNTAX(s_atcall_cc,"@call-with-current-continuation", scm_makmmacro, scm_m_cont); SCM_GLOBAL_SYMBOL(scm_sym_atcall_cc,s_atcall_cc); SCM scm_m_cont (SCM xorig, SCM env SCM_UNUSED) { SCM_ASSYNT (scm_ilength (SCM_CDR (xorig)) == 1, scm_s_expression, s_atcall_cc); return scm_cons (SCM_IM_CONT, SCM_CDR (xorig)); } /* Multi-language support */ SCM_GLOBAL_SYMBOL (scm_lisp_nil, "nil"); SCM_GLOBAL_SYMBOL (scm_t_lisp, "t"); SCM_SYNTAX (s_nil_cond, "nil-cond", scm_makmmacro, scm_m_nil_cond); SCM scm_m_nil_cond (SCM xorig, SCM env SCM_UNUSED) { long len = scm_ilength (SCM_CDR (xorig)); SCM_ASSYNT (len >= 1 && (len & 1) == 1, scm_s_expression, "nil-cond"); return scm_cons (SCM_IM_NIL_COND, SCM_CDR (xorig)); } SCM_SYNTAX (s_nil_ify, "nil-ify", scm_makmmacro, scm_m_nil_ify); SCM scm_m_nil_ify (SCM xorig, SCM env SCM_UNUSED) { SCM_ASSYNT (scm_ilength (SCM_CDR (xorig)) == 1, scm_s_expression, "nil-ify"); return scm_cons (SCM_IM_NIL_IFY, SCM_CDR (xorig)); } SCM_SYNTAX (s_t_ify, "t-ify", scm_makmmacro, scm_m_t_ify); SCM scm_m_t_ify (SCM xorig, SCM env SCM_UNUSED) { SCM_ASSYNT (scm_ilength (SCM_CDR (xorig)) == 1, scm_s_expression, "t-ify"); return scm_cons (SCM_IM_T_IFY, SCM_CDR (xorig)); } SCM_SYNTAX (s_0_cond, "0-cond", scm_makmmacro, scm_m_0_cond); SCM scm_m_0_cond (SCM xorig, SCM env SCM_UNUSED) { long len = scm_ilength (SCM_CDR (xorig)); SCM_ASSYNT (len >= 1 && (len & 1) == 1, scm_s_expression, "0-cond"); return scm_cons (SCM_IM_0_COND, SCM_CDR (xorig)); } SCM_SYNTAX (s_0_ify, "0-ify", scm_makmmacro, scm_m_0_ify); SCM scm_m_0_ify (SCM xorig, SCM env SCM_UNUSED) { SCM_ASSYNT (scm_ilength (SCM_CDR (xorig)) == 1, scm_s_expression, "0-ify"); return scm_cons (SCM_IM_0_IFY, SCM_CDR (xorig)); } SCM_SYNTAX (s_1_ify, "1-ify", scm_makmmacro, scm_m_1_ify); SCM scm_m_1_ify (SCM xorig, SCM env SCM_UNUSED) { SCM_ASSYNT (scm_ilength (SCM_CDR (xorig)) == 1, scm_s_expression, "1-ify"); return scm_cons (SCM_IM_1_IFY, SCM_CDR (xorig)); } SCM_SYNTAX (s_atfop, "@fop", scm_makmmacro, scm_m_atfop); SCM scm_m_atfop (SCM xorig, SCM env SCM_UNUSED) { SCM x = SCM_CDR (xorig), var; SCM_ASSYNT (scm_ilength (x) >= 1, scm_s_expression, "@fop"); var = scm_symbol_fref (SCM_CAR (x)); SCM_ASSYNT (SCM_VARIABLEP (var), "Symbol's function definition is void", NULL); SCM_SET_CELL_WORD_0 (x, SCM_UNPACK (var) + scm_tc3_cons_gloc); return x; } SCM_SYNTAX (s_atbind, "@bind", scm_makmmacro, scm_m_atbind); SCM scm_m_atbind (SCM xorig, SCM env) { SCM x = SCM_CDR (xorig); SCM_ASSYNT (scm_ilength (x) > 1, scm_s_expression, "@bind"); if (SCM_IMP (env)) env = SCM_BOOL_F; else { while (SCM_NIMP (SCM_CDR (env))) env = SCM_CDR (env); env = SCM_CAR (env); if (SCM_CONSP (env)) env = SCM_BOOL_F; } x = SCM_CAR (x); while (SCM_NIMP (x)) { SCM_SET_CELL_WORD_0 (x, SCM_UNPACK (scm_sym2var (SCM_CAR (x), env, SCM_BOOL_T)) + scm_tc3_cons_gloc); x = SCM_CDR (x); } return scm_cons (SCM_IM_BIND, SCM_CDR (xorig)); } SCM_SYNTAX (s_at_call_with_values, "@call-with-values", scm_makmmacro, scm_m_at_call_with_values); SCM_GLOBAL_SYMBOL(scm_sym_at_call_with_values, s_at_call_with_values); SCM scm_m_at_call_with_values (SCM xorig, SCM env SCM_UNUSED) { SCM_ASSYNT (scm_ilength (SCM_CDR (xorig)) == 2, scm_s_expression, s_at_call_with_values); return scm_cons (SCM_IM_CALL_WITH_VALUES, SCM_CDR (xorig)); } SCM scm_m_expand_body (SCM xorig, SCM env) { SCM x = SCM_CDR (xorig), defs = SCM_EOL; char *what = SCM_ISYMCHARS (SCM_CAR (xorig)) + 2; while (SCM_NIMP (x)) { SCM form = SCM_CAR (x); if (!SCM_CONSP (form)) break; if (!SCM_SYMBOLP (SCM_CAR (form))) break; form = scm_macroexp (scm_cons_source (form, SCM_CAR (form), SCM_CDR (form)), env); if (SCM_EQ_P (SCM_IM_DEFINE, SCM_CAR (form))) { defs = scm_cons (SCM_CDR (form), defs); x = SCM_CDR (x); } else if (!SCM_IMP (defs)) { break; } else if (SCM_EQ_P (SCM_IM_BEGIN, SCM_CAR (form))) { x = scm_append (scm_cons2 (SCM_CDR (form), SCM_CDR (x), SCM_EOL)); } else { x = scm_cons (form, SCM_CDR (x)); break; } } SCM_ASSYNT (SCM_NIMP (x), scm_s_body, what); if (SCM_NIMP (defs)) { x = scm_cons (scm_m_letrec1 (SCM_IM_LETREC, SCM_IM_DEFINE, scm_cons2 (scm_sym_define, defs, x), env), SCM_EOL); } SCM_DEFER_INTS; SCM_SETCAR (xorig, SCM_CAR (x)); SCM_SETCDR (xorig, SCM_CDR (x)); SCM_ALLOW_INTS; return xorig; } SCM scm_macroexp (SCM x, SCM env) { SCM res, proc, orig_sym; /* Don't bother to produce error messages here. We get them when we eventually execute the code for real. */ macro_tail: orig_sym = SCM_CAR (x); if (!SCM_SYMBOLP (orig_sym)) return x; #ifdef USE_THREADS { SCM *proc_ptr = scm_lookupcar1 (x, env, 0); if (proc_ptr == NULL) { /* We have lost the race. */ goto macro_tail; } proc = *proc_ptr; } #else proc = *scm_lookupcar (x, env, 0); #endif /* Only handle memoizing macros. `Acros' and `macros' are really special forms and should not be evaluated here. */ if (!SCM_MACROP (proc) || SCM_MACRO_TYPE (proc) != 2) return x; SCM_SETCAR (x, orig_sym); /* Undo memoizing effect of lookupcar */ res = scm_apply (SCM_MACRO_CODE (proc), x, scm_cons (env, scm_listofnull)); if (scm_ilength (res) <= 0) res = scm_cons2 (SCM_IM_BEGIN, res, SCM_EOL); SCM_DEFER_INTS; SCM_SETCAR (x, SCM_CAR (res)); SCM_SETCDR (x, SCM_CDR (res)); SCM_ALLOW_INTS; goto macro_tail; } /* scm_unmemocopy takes a memoized expression together with its * environment and rewrites it to its original form. Thus, it is the * inversion of the rewrite rules above. The procedure is not * optimized for speed. It's used in scm_iprin1 when printing the * code of a closure, in scm_procedure_source, in display_frame when * generating the source for a stackframe in a backtrace, and in * display_expression. * * Unmemoizing is not a realiable process. You can not in general * expect to get the original source back. * * However, GOOPS currently relies on this for method compilation. * This ought to change. */ #define SCM_BIT8(x) (127 & SCM_UNPACK (x)) static SCM unmemocopy (SCM x, SCM env) { SCM ls, z; #ifdef DEBUG_EXTENSIONS SCM p; #endif if (SCM_NCELLP (x) || SCM_NECONSP (x)) return x; #ifdef DEBUG_EXTENSIONS p = scm_whash_lookup (scm_source_whash, x); #endif switch (SCM_TYP7 (x)) { case SCM_BIT8(SCM_IM_AND): ls = z = scm_cons (scm_sym_and, SCM_UNSPECIFIED); break; case SCM_BIT8(SCM_IM_BEGIN): ls = z = scm_cons (scm_sym_begin, SCM_UNSPECIFIED); break; case SCM_BIT8(SCM_IM_CASE): ls = z = scm_cons (scm_sym_case, SCM_UNSPECIFIED); break; case SCM_BIT8(SCM_IM_COND): ls = z = scm_cons (scm_sym_cond, SCM_UNSPECIFIED); break; case SCM_BIT8(SCM_IM_DO): ls = scm_cons (scm_sym_do, SCM_UNSPECIFIED); goto transform; case SCM_BIT8(SCM_IM_IF): ls = z = scm_cons (scm_sym_if, SCM_UNSPECIFIED); break; case SCM_BIT8(SCM_IM_LET): ls = scm_cons (scm_sym_let, SCM_UNSPECIFIED); goto transform; case SCM_BIT8(SCM_IM_LETREC): { SCM f, v, e, s; ls = scm_cons (scm_sym_letrec, SCM_UNSPECIFIED); transform: x = SCM_CDR (x); /* binding names */ f = v = SCM_CAR (x); x = SCM_CDR (x); z = EXTEND_ENV (f, SCM_EOL, env); /* inits */ e = scm_reverse (unmemocopy (SCM_CAR (x), SCM_EQ_P (SCM_CAR (ls), scm_sym_letrec) ? z : env)); env = z; /* increments */ s = SCM_EQ_P (SCM_CAR (ls), scm_sym_do) ? scm_reverse (unmemocopy (SCM_CDR (SCM_CDR (SCM_CDR (x))), env)) : f; /* build transformed binding list */ z = SCM_EOL; while (SCM_NIMP (v)) { z = scm_acons (SCM_CAR (v), scm_cons (SCM_CAR (e), SCM_EQ_P (SCM_CAR (s), SCM_CAR (v)) ? SCM_EOL : scm_cons (SCM_CAR (s), SCM_EOL)), z); v = SCM_CDR (v); e = SCM_CDR (e); s = SCM_CDR (s); } z = scm_cons (z, SCM_UNSPECIFIED); SCM_SETCDR (ls, z); if (SCM_EQ_P (SCM_CAR (ls), scm_sym_do)) { x = SCM_CDR (x); /* test clause */ SCM_SETCDR (z, scm_cons (unmemocopy (SCM_CAR (x), env), SCM_UNSPECIFIED)); z = SCM_CDR (z); x = (SCM) (SCM_CARLOC (SCM_CDR (x)) - 1); /* body forms are now to be found in SCM_CDR (x) (this is how *real* code look like! :) */ } break; } case SCM_BIT8(SCM_IM_LETSTAR): { SCM b, y; x = SCM_CDR (x); b = SCM_CAR (x); y = SCM_EOL; if SCM_IMP (b) { env = EXTEND_ENV (SCM_EOL, SCM_EOL, env); goto letstar; } y = z = scm_acons (SCM_CAR (b), unmemocar ( scm_cons (unmemocopy (SCM_CAR (SCM_CDR (b)), env), SCM_EOL), env), SCM_UNSPECIFIED); env = EXTEND_ENV (SCM_CAR (b), SCM_BOOL_F, env); b = SCM_CDR (SCM_CDR (b)); if (SCM_IMP (b)) { SCM_SETCDR (y, SCM_EOL); ls = scm_cons (scm_sym_let, z = scm_cons (y, SCM_UNSPECIFIED)); break; } do { SCM_SETCDR (z, scm_acons (SCM_CAR (b), unmemocar ( scm_cons (unmemocopy (SCM_CAR (SCM_CDR (b)), env), SCM_EOL), env), SCM_UNSPECIFIED)); z = SCM_CDR (z); env = EXTEND_ENV (SCM_CAR (b), SCM_BOOL_F, env); b = SCM_CDR (SCM_CDR (b)); } while (SCM_NIMP (b)); SCM_SETCDR (z, SCM_EOL); letstar: ls = scm_cons (scm_sym_letstar, z = scm_cons (y, SCM_UNSPECIFIED)); break; } case SCM_BIT8(SCM_IM_OR): ls = z = scm_cons (scm_sym_or, SCM_UNSPECIFIED); break; case SCM_BIT8(SCM_IM_LAMBDA): x = SCM_CDR (x); ls = scm_cons (scm_sym_lambda, z = scm_cons (SCM_CAR (x), SCM_UNSPECIFIED)); env = EXTEND_ENV (SCM_CAR (x), SCM_EOL, env); break; case SCM_BIT8(SCM_IM_QUOTE): ls = z = scm_cons (scm_sym_quote, SCM_UNSPECIFIED); break; case SCM_BIT8(SCM_IM_SET_X): ls = z = scm_cons (scm_sym_set_x, SCM_UNSPECIFIED); break; case SCM_BIT8(SCM_IM_DEFINE): { SCM n; x = SCM_CDR (x); ls = scm_cons (scm_sym_define, z = scm_cons (n = SCM_CAR (x), SCM_UNSPECIFIED)); if (SCM_NNULLP (env)) SCM_SETCAR (SCM_CAR (env), scm_cons (n, SCM_CAR (SCM_CAR (env)))); break; } case SCM_BIT8(SCM_MAKISYM (0)): z = SCM_CAR (x); if (!SCM_ISYMP (z)) goto unmemo; switch (SCM_ISYMNUM (z)) { case (SCM_ISYMNUM (SCM_IM_APPLY)): ls = z = scm_cons (scm_sym_atapply, SCM_UNSPECIFIED); goto loop; case (SCM_ISYMNUM (SCM_IM_CONT)): ls = z = scm_cons (scm_sym_atcall_cc, SCM_UNSPECIFIED); goto loop; case (SCM_ISYMNUM (SCM_IM_DELAY)): ls = z = scm_cons (scm_sym_delay, SCM_UNSPECIFIED); x = SCM_CDR (x); goto loop; case (SCM_ISYMNUM (SCM_IM_CALL_WITH_VALUES)): ls = z = scm_cons (scm_sym_at_call_with_values, SCM_UNSPECIFIED); goto loop; default: /* appease the Sun compiler god: */ ; } unmemo: default: ls = z = unmemocar (scm_cons (unmemocopy (SCM_CAR (x), env), SCM_UNSPECIFIED), env); } loop: while (SCM_CELLP (x = SCM_CDR (x)) && SCM_ECONSP (x)) { if (SCM_ISYMP (SCM_CAR (x))) /* skip body markers */ continue; SCM_SETCDR (z, unmemocar (scm_cons (unmemocopy (SCM_CAR (x), env), SCM_UNSPECIFIED), env)); z = SCM_CDR (z); } SCM_SETCDR (z, x); #ifdef DEBUG_EXTENSIONS if (SCM_NFALSEP (p)) scm_whash_insert (scm_source_whash, ls, p); #endif return ls; } SCM scm_unmemocopy (SCM x, SCM env) { if (SCM_NNULLP (env)) /* Make a copy of the lowest frame to protect it from modifications by SCM_IM_DEFINE */ return unmemocopy (x, scm_cons (SCM_CAR (env), SCM_CDR (env))); else return unmemocopy (x, env); } #ifndef SCM_RECKLESS int scm_badargsp (SCM formals, SCM args) { while (SCM_NIMP (formals)) { if (SCM_NCONSP (formals)) return 0; if (SCM_IMP(args)) return 1; formals = SCM_CDR (formals); args = SCM_CDR (args); } return SCM_NNULLP (args) ? 1 : 0; } #endif static int scm_badformalsp (SCM closure, int n) { SCM formals = SCM_CLOSURE_FORMALS (closure); while (!SCM_NULLP (formals)) { if (!SCM_CONSP (formals)) return 0; if (n == 0) return 1; --n; formals = SCM_CDR (formals); } return n; } SCM scm_eval_args (SCM l, SCM env, SCM proc) { SCM results = SCM_EOL, *lloc = &results, res; while (!SCM_IMP (l)) { #ifdef SCM_CAUTIOUS if (SCM_CONSP (l)) { if (SCM_IMP (SCM_CAR (l))) res = SCM_EVALIM (SCM_CAR (l), env); else res = EVALCELLCAR (l, env); } else if (SCM_TYP3 (l) == scm_tc3_cons_gloc) { scm_t_bits vcell = SCM_STRUCT_VTABLE_DATA (l) [scm_vtable_index_vcell]; if (vcell == 0) res = SCM_CAR (l); /* struct planted in code */ else res = SCM_GLOC_VAL (SCM_CAR (l)); } else goto wrongnumargs; #else res = EVALCAR (l, env); #endif *lloc = scm_cons (res, SCM_EOL); lloc = SCM_CDRLOC (*lloc); l = SCM_CDR (l); } #ifdef SCM_CAUTIOUS if (!SCM_NULLP (l)) { wrongnumargs: scm_wrong_num_args (proc); } #endif return results; } SCM scm_eval_body (SCM code, SCM env) { SCM next; again: next = code; while (SCM_NNULLP (next = SCM_CDR (next))) { if (SCM_IMP (SCM_CAR (code))) { if (SCM_ISYMP (SCM_CAR (code))) { code = scm_m_expand_body (code, env); goto again; } } else SCM_XEVAL (SCM_CAR (code), env); code = next; } return SCM_XEVALCAR (code, env); } #endif /* !DEVAL */ /* SECTION: This code is specific for the debugging support. One * branch is read when DEVAL isn't defined, the other when DEVAL is * defined. */ #ifndef DEVAL #define SCM_APPLY scm_apply #define PREP_APPLY(proc, args) #define ENTER_APPLY #define RETURN(x) return x; #ifdef STACK_CHECKING #ifndef NO_CEVAL_STACK_CHECKING #define EVAL_STACK_CHECKING #endif #endif #else /* !DEVAL */ #undef SCM_CEVAL #define SCM_CEVAL scm_deval /* Substitute all uses of scm_ceval */ #undef SCM_APPLY #define SCM_APPLY scm_dapply #undef PREP_APPLY #define PREP_APPLY(p, l) \ { ++debug.info; debug.info->a.proc = p; debug.info->a.args = l; } #undef ENTER_APPLY #define ENTER_APPLY \ do { \ SCM_SET_ARGSREADY (debug);\ if (CHECK_APPLY && SCM_TRAPS_P)\ if (SCM_APPLY_FRAME_P || (SCM_TRACE_P && PROCTRACEP (proc)))\ {\ SCM tmp, tail = SCM_BOOL(SCM_TRACED_FRAME_P (debug)); \ SCM_SET_TRACED_FRAME (debug); \ if (SCM_CHEAPTRAPS_P)\ {\ tmp = scm_make_debugobj (&debug);\ scm_ithrow (scm_sym_apply_frame, scm_cons2 (tmp, tail, SCM_EOL), 0);\ }\ else\ {\ int first;\ tmp = scm_make_continuation (&first);\ if (first)\ scm_ithrow (scm_sym_apply_frame, scm_cons2 (tmp, tail, SCM_EOL), 0);\ }\ }\ } while (0) #undef RETURN #define RETURN(e) {proc = (e); goto exit;} #ifdef STACK_CHECKING #ifndef EVAL_STACK_CHECKING #define EVAL_STACK_CHECKING #endif #endif /* scm_ceval_ptr points to the currently selected evaluator. * *fixme*: Although efficiency is important here, this state variable * should probably not be a global. It should be related to the * current repl. */ SCM (*scm_ceval_ptr) (SCM x, SCM env); /* scm_last_debug_frame contains a pointer to the last debugging * information stack frame. It is accessed very often from the * debugging evaluator, so it should probably not be indirectly * addressed. Better to save and restore it from the current root at * any stack swaps. */ #ifndef USE_THREADS scm_t_debug_frame *scm_last_debug_frame; #endif /* scm_debug_eframe_size is the number of slots available for pseudo * stack frames at each real stack frame. */ long scm_debug_eframe_size; int scm_debug_mode, scm_check_entry_p, scm_check_apply_p, scm_check_exit_p; long scm_eval_stack; scm_t_option scm_eval_opts[] = { { SCM_OPTION_INTEGER, "stack", 22000, "Size of thread stacks (in machine words)." } }; scm_t_option scm_debug_opts[] = { { SCM_OPTION_BOOLEAN, "cheap", 1, "*Flyweight representation of the stack at traps." }, { SCM_OPTION_BOOLEAN, "breakpoints", 0, "*Check for breakpoints." }, { SCM_OPTION_BOOLEAN, "trace", 0, "*Trace mode." }, { SCM_OPTION_BOOLEAN, "procnames", 1, "Record procedure names at definition." }, { SCM_OPTION_BOOLEAN, "backwards", 0, "Display backtrace in anti-chronological order." }, { SCM_OPTION_INTEGER, "width", 79, "Maximal width of backtrace." }, { SCM_OPTION_INTEGER, "indent", 10, "Maximal indentation in backtrace." }, { SCM_OPTION_INTEGER, "frames", 3, "Maximum number of tail-recursive frames in backtrace." }, { SCM_OPTION_INTEGER, "maxdepth", 1000, "Maximal number of stored backtrace frames." }, { SCM_OPTION_INTEGER, "depth", 20, "Maximal length of printed backtrace." }, { SCM_OPTION_BOOLEAN, "backtrace", 0, "Show backtrace on error." }, { SCM_OPTION_BOOLEAN, "debug", 0, "Use the debugging evaluator." }, { SCM_OPTION_INTEGER, "stack", 20000, "Stack size limit (measured in words; 0 = no check)." }, { SCM_OPTION_SCM, "show-file-name", SCM_BOOL_T, "Show file names and line numbers in backtraces when not `#f'. A value of `base' displays only base names, while `#t' displays full names."} }; scm_t_option scm_evaluator_trap_table[] = { { SCM_OPTION_BOOLEAN, "traps", 0, "Enable evaluator traps." }, { SCM_OPTION_BOOLEAN, "enter-frame", 0, "Trap when eval enters new frame." }, { SCM_OPTION_BOOLEAN, "apply-frame", 0, "Trap when entering apply." }, { SCM_OPTION_BOOLEAN, "exit-frame", 0, "Trap when exiting eval or apply." } }; SCM_DEFINE (scm_eval_options_interface, "eval-options-interface", 0, 1, 0, (SCM setting), "Option interface for the evaluation options. Instead of using\n" "this procedure directly, use the procedures @code{eval-enable},\n" "@code{eval-disable}, @code{eval-set!} and @var{eval-options}.") #define FUNC_NAME s_scm_eval_options_interface { SCM ans; SCM_DEFER_INTS; ans = scm_options (setting, scm_eval_opts, SCM_N_EVAL_OPTIONS, FUNC_NAME); scm_eval_stack = SCM_EVAL_STACK * sizeof (void *); SCM_ALLOW_INTS; return ans; } #undef FUNC_NAME SCM_DEFINE (scm_evaluator_traps, "evaluator-traps-interface", 0, 1, 0, (SCM setting), "Option interface for the evaluator trap options.") #define FUNC_NAME s_scm_evaluator_traps { SCM ans; SCM_DEFER_INTS; ans = scm_options (setting, scm_evaluator_trap_table, SCM_N_EVALUATOR_TRAPS, FUNC_NAME); SCM_RESET_DEBUG_MODE; SCM_ALLOW_INTS; return ans; } #undef FUNC_NAME SCM scm_deval_args (SCM l, SCM env, SCM proc, SCM *lloc) { SCM *results = lloc, res; while (!SCM_IMP (l)) { #ifdef SCM_CAUTIOUS if (SCM_CONSP (l)) { if (SCM_IMP (SCM_CAR (l))) res = SCM_EVALIM (SCM_CAR (l), env); else res = EVALCELLCAR (l, env); } else if (SCM_TYP3 (l) == scm_tc3_cons_gloc) { scm_t_bits vcell = SCM_STRUCT_VTABLE_DATA (l) [scm_vtable_index_vcell]; if (vcell == 0) res = SCM_CAR (l); /* struct planted in code */ else res = SCM_GLOC_VAL (SCM_CAR (l)); } else goto wrongnumargs; #else res = EVALCAR (l, env); #endif *lloc = scm_cons (res, SCM_EOL); lloc = SCM_CDRLOC (*lloc); l = SCM_CDR (l); } #ifdef SCM_CAUTIOUS if (!SCM_NULLP (l)) { wrongnumargs: scm_wrong_num_args (proc); } #endif return *results; } #endif /* !DEVAL */ /* SECTION: Some local definitions for the evaluator. */ /* Update the toplevel environment frame ENV so that it refers to the current module. */ #define UPDATE_TOPLEVEL_ENV(env) \ do { \ SCM p = scm_current_module_lookup_closure (); \ if (p != SCM_CAR(env)) \ env = scm_top_level_env (p); \ } while (0) #ifndef DEVAL #define CHECK_EQVISH(A,B) (SCM_EQ_P ((A), (B)) || (SCM_NFALSEP (scm_eqv_p ((A), (B))))) #endif /* DEVAL */ #define BUILTIN_RPASUBR /* Handle rpsubrs and asubrs without calling apply */ /* SECTION: This is the evaluator. Like any real monster, it has * three heads. This code is compiled twice. */ #if 0 SCM scm_ceval (SCM x, SCM env) {} #endif #if 0 SCM scm_deval (SCM x, SCM env) {} #endif SCM SCM_CEVAL (SCM x, SCM env) { union { SCM *lloc; SCM arg1; } t; SCM proc, arg2, orig_sym; #ifdef DEVAL scm_t_debug_frame debug; scm_t_debug_info *debug_info_end; debug.prev = scm_last_debug_frame; debug.status = scm_debug_eframe_size; /* * The debug.vect contains twice as much scm_t_debug_info frames as the * user has specified with (debug-set! frames ). * * Even frames are eval frames, odd frames are apply frames. */ debug.vect = (scm_t_debug_info *) alloca (scm_debug_eframe_size * sizeof (debug.vect[0])); debug.info = debug.vect; debug_info_end = debug.vect + scm_debug_eframe_size; scm_last_debug_frame = &debug; #endif #ifdef EVAL_STACK_CHECKING if (scm_stack_checking_enabled_p && SCM_STACK_OVERFLOW_P ((SCM_STACKITEM *) &proc)) { #ifdef DEVAL debug.info->e.exp = x; debug.info->e.env = env; #endif scm_report_stack_overflow (); } #endif #ifdef DEVAL goto start; #endif loopnoap: PREP_APPLY (SCM_UNDEFINED, SCM_EOL); loop: #ifdef DEVAL SCM_CLEAR_ARGSREADY (debug); if (SCM_OVERFLOWP (debug)) --debug.info; /* * In theory, this should be the only place where it is necessary to * check for space in debug.vect since both eval frames and * available space are even. * * For this to be the case, however, it is necessary that primitive * special forms which jump back to `loop', `begin' or some similar * label call PREP_APPLY. A convenient way to do this is to jump to * `loopnoap' or `cdrxnoap'. */ else if (++debug.info >= debug_info_end) { SCM_SET_OVERFLOW (debug); debug.info -= 2; } start: debug.info->e.exp = x; debug.info->e.env = env; if (CHECK_ENTRY && SCM_TRAPS_P) if (SCM_ENTER_FRAME_P || (SCM_BREAKPOINTS_P && SRCBRKP (x))) { SCM tail = SCM_BOOL(SCM_TAILRECP (debug)); SCM_SET_TAILREC (debug); if (SCM_CHEAPTRAPS_P) t.arg1 = scm_make_debugobj (&debug); else { int first; SCM val = scm_make_continuation (&first); if (first) t.arg1 = val; else { x = val; if (SCM_IMP (x)) { RETURN (x); } else /* This gives the possibility for the debugger to modify the source expression before evaluation. */ goto dispatch; } } scm_ithrow (scm_sym_enter_frame, scm_cons2 (t.arg1, tail, scm_cons (scm_unmemocopy (x, env), SCM_EOL)), 0); } #endif #if defined (USE_THREADS) || defined (DEVAL) dispatch: #endif SCM_TICK; switch (SCM_TYP7 (x)) { case scm_tc7_symbol: /* Only happens when called at top level. */ x = scm_cons (x, SCM_UNDEFINED); goto retval; case SCM_BIT8(SCM_IM_AND): x = SCM_CDR (x); t.arg1 = x; while (SCM_NNULLP (t.arg1 = SCM_CDR (t.arg1))) if (SCM_FALSEP (EVALCAR (x, env))) { RETURN (SCM_BOOL_F); } else x = t.arg1; PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto carloop; case SCM_BIT8(SCM_IM_BEGIN): /* (currently unused) cdrxnoap: */ PREP_APPLY (SCM_UNDEFINED, SCM_EOL); /* (currently unused) cdrxbegin: */ x = SCM_CDR (x); begin: /* If we are on toplevel with a lookup closure, we need to sync with the current module. */ if (SCM_CONSP (env) && !SCM_CONSP (SCM_CAR (env))) { t.arg1 = x; UPDATE_TOPLEVEL_ENV (env); while (!SCM_NULLP (t.arg1 = SCM_CDR (t.arg1))) { EVALCAR (x, env); x = t.arg1; UPDATE_TOPLEVEL_ENV (env); } goto carloop; } else goto nontoplevel_begin; nontoplevel_cdrxnoap: PREP_APPLY (SCM_UNDEFINED, SCM_EOL); nontoplevel_cdrxbegin: x = SCM_CDR (x); nontoplevel_begin: t.arg1 = x; while (!SCM_NULLP (t.arg1 = SCM_CDR (t.arg1))) { if (SCM_IMP (SCM_CAR (x))) { if (SCM_ISYMP (SCM_CAR (x))) { x = scm_m_expand_body (x, env); goto nontoplevel_begin; } else SCM_VALIDATE_NON_EMPTY_COMBINATION (SCM_CAR (x)); } else SCM_CEVAL (SCM_CAR (x), env); x = t.arg1; } carloop: /* scm_eval car of last form in list */ if (!SCM_CELLP (SCM_CAR (x))) { x = SCM_CAR (x); RETURN (SCM_IMP (x) ? SCM_EVALIM (x, env) : SCM_GLOC_VAL (x)) } if (SCM_SYMBOLP (SCM_CAR (x))) { retval: RETURN (*scm_lookupcar (x, env, 1)) } x = SCM_CAR (x); goto loop; /* tail recurse */ case SCM_BIT8(SCM_IM_CASE): x = SCM_CDR (x); t.arg1 = EVALCAR (x, env); while (SCM_NIMP (x = SCM_CDR (x))) { proc = SCM_CAR (x); if (SCM_EQ_P (scm_sym_else, SCM_CAR (proc))) { x = SCM_CDR (proc); PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto begin; } proc = SCM_CAR (proc); while (SCM_NIMP (proc)) { if (CHECK_EQVISH (SCM_CAR (proc), t.arg1)) { x = SCM_CDR (SCM_CAR (x)); PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto begin; } proc = SCM_CDR (proc); } } RETURN (SCM_UNSPECIFIED) case SCM_BIT8(SCM_IM_COND): while (!SCM_IMP (x = SCM_CDR (x))) { proc = SCM_CAR (x); t.arg1 = EVALCAR (proc, env); if (SCM_NFALSEP (t.arg1)) { x = SCM_CDR (proc); if (SCM_NULLP (x)) { RETURN (t.arg1) } if (!SCM_EQ_P (scm_sym_arrow, SCM_CAR (x))) { PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto begin; } proc = SCM_CDR (x); proc = EVALCAR (proc, env); SCM_ASRTGO (SCM_NIMP (proc), badfun); PREP_APPLY (proc, scm_cons (t.arg1, SCM_EOL)); ENTER_APPLY; if (SCM_CLOSUREP(proc) && scm_badformalsp (proc, 1)) goto umwrongnumargs; goto evap1; } } RETURN (SCM_UNSPECIFIED) case SCM_BIT8(SCM_IM_DO): x = SCM_CDR (x); proc = SCM_CAR (SCM_CDR (x)); /* inits */ t.arg1 = SCM_EOL; /* values */ while (SCM_NIMP (proc)) { t.arg1 = scm_cons (EVALCAR (proc, env), t.arg1); proc = SCM_CDR (proc); } env = EXTEND_ENV (SCM_CAR (x), t.arg1, env); x = SCM_CDR (SCM_CDR (x)); while (proc = SCM_CAR (x), SCM_FALSEP (EVALCAR (proc, env))) { for (proc = SCM_CADR (x); SCM_NIMP (proc); proc = SCM_CDR (proc)) { t.arg1 = SCM_CAR (proc); /* body */ SIDEVAL (t.arg1, env); } for (t.arg1 = SCM_EOL, proc = SCM_CDDR (x); SCM_NIMP (proc); proc = SCM_CDR (proc)) t.arg1 = scm_cons (EVALCAR (proc, env), t.arg1); /* steps */ env = EXTEND_ENV (SCM_CAR (SCM_CAR (env)), t.arg1, SCM_CDR (env)); } x = SCM_CDR (proc); if (SCM_NULLP (x)) RETURN (SCM_UNSPECIFIED); PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto nontoplevel_begin; case SCM_BIT8(SCM_IM_IF): x = SCM_CDR (x); if (SCM_NFALSEP (EVALCAR (x, env))) x = SCM_CDR (x); else if (SCM_IMP (x = SCM_CDR (SCM_CDR (x)))) { RETURN (SCM_UNSPECIFIED); } PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto carloop; case SCM_BIT8(SCM_IM_LET): x = SCM_CDR (x); proc = SCM_CAR (SCM_CDR (x)); t.arg1 = SCM_EOL; do { t.arg1 = scm_cons (EVALCAR (proc, env), t.arg1); } while (SCM_NIMP (proc = SCM_CDR (proc))); env = EXTEND_ENV (SCM_CAR (x), t.arg1, env); x = SCM_CDR (x); goto nontoplevel_cdrxnoap; case SCM_BIT8(SCM_IM_LETREC): x = SCM_CDR (x); env = EXTEND_ENV (SCM_CAR (x), scm_undefineds, env); x = SCM_CDR (x); proc = SCM_CAR (x); t.arg1 = SCM_EOL; do { t.arg1 = scm_cons (EVALCAR (proc, env), t.arg1); } while (SCM_NIMP (proc = SCM_CDR (proc))); SCM_SETCDR (SCM_CAR (env), t.arg1); goto nontoplevel_cdrxnoap; case SCM_BIT8(SCM_IM_LETSTAR): x = SCM_CDR (x); proc = SCM_CAR (x); if (SCM_IMP (proc)) { env = EXTEND_ENV (SCM_EOL, SCM_EOL, env); goto nontoplevel_cdrxnoap; } do { t.arg1 = SCM_CAR (proc); proc = SCM_CDR (proc); env = EXTEND_ENV (t.arg1, EVALCAR (proc, env), env); } while (SCM_NIMP (proc = SCM_CDR (proc))); goto nontoplevel_cdrxnoap; case SCM_BIT8(SCM_IM_OR): x = SCM_CDR (x); t.arg1 = x; while (!SCM_NULLP (t.arg1 = SCM_CDR (t.arg1))) { x = EVALCAR (x, env); if (!SCM_FALSEP (x)) { RETURN (x); } x = t.arg1; } PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto carloop; case SCM_BIT8(SCM_IM_LAMBDA): RETURN (scm_closure (SCM_CDR (x), env)); case SCM_BIT8(SCM_IM_QUOTE): RETURN (SCM_CAR (SCM_CDR (x))); case SCM_BIT8(SCM_IM_SET_X): x = SCM_CDR (x); proc = SCM_CAR (x); switch (SCM_ITAG3 (proc)) { case scm_tc3_cons: t.lloc = scm_lookupcar (x, env, 1); break; case scm_tc3_cons_gloc: t.lloc = SCM_GLOC_VAL_LOC (proc); break; #ifdef MEMOIZE_LOCALS case scm_tc3_imm24: t.lloc = scm_ilookup (proc, env); break; #endif } x = SCM_CDR (x); *t.lloc = EVALCAR (x, env); #ifdef SICP RETURN (*t.lloc); #else RETURN (SCM_UNSPECIFIED); #endif case SCM_BIT8(SCM_IM_DEFINE): /* only for internal defines */ scm_misc_error (NULL, "Bad define placement", SCM_EOL); /* new syntactic forms go here. */ case SCM_BIT8(SCM_MAKISYM (0)): proc = SCM_CAR (x); SCM_ASRTGO (SCM_ISYMP (proc), badfun); switch SCM_ISYMNUM (proc) { case (SCM_ISYMNUM (SCM_IM_APPLY)): proc = SCM_CDR (x); proc = EVALCAR (proc, env); SCM_ASRTGO (SCM_NIMP (proc), badfun); if (SCM_CLOSUREP (proc)) { SCM argl, tl; PREP_APPLY (proc, SCM_EOL); t.arg1 = SCM_CDR (SCM_CDR (x)); t.arg1 = EVALCAR (t.arg1, env); apply_closure: /* Go here to tail-call a closure. PROC is the closure and T.ARG1 is the list of arguments. Do not forget to call PREP_APPLY. */ #ifdef DEVAL debug.info->a.args = t.arg1; #endif #ifndef SCM_RECKLESS if (scm_badargsp (SCM_CLOSURE_FORMALS (proc), t.arg1)) goto wrongnumargs; #endif ENTER_APPLY; /* Copy argument list */ if (SCM_IMP (t.arg1)) argl = t.arg1; else { argl = tl = scm_cons (SCM_CAR (t.arg1), SCM_UNSPECIFIED); while (SCM_NIMP (t.arg1 = SCM_CDR (t.arg1)) && SCM_CONSP (t.arg1)) { SCM_SETCDR (tl, scm_cons (SCM_CAR (t.arg1), SCM_UNSPECIFIED)); tl = SCM_CDR (tl); } SCM_SETCDR (tl, t.arg1); } env = EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), argl, SCM_ENV (proc)); x = SCM_CODE (proc); goto nontoplevel_cdrxbegin; } proc = scm_f_apply; goto evapply; case (SCM_ISYMNUM (SCM_IM_CONT)): { int first; SCM val = scm_make_continuation (&first); if (first) t.arg1 = val; else RETURN (val); } proc = SCM_CDR (x); proc = evalcar (proc, env); SCM_ASRTGO (SCM_NIMP (proc), badfun); PREP_APPLY (proc, scm_cons (t.arg1, SCM_EOL)); ENTER_APPLY; if (SCM_CLOSUREP(proc) && scm_badformalsp (proc, 1)) goto umwrongnumargs; goto evap1; case (SCM_ISYMNUM (SCM_IM_DELAY)): RETURN (scm_makprom (scm_closure (SCM_CDR (x), env))) case (SCM_ISYMNUM (SCM_IM_DISPATCH)): proc = SCM_CADR (x); /* unevaluated operands */ PREP_APPLY (SCM_UNDEFINED, SCM_EOL); if (SCM_IMP (proc)) arg2 = *scm_ilookup (proc, env); else if (SCM_NCONSP (proc)) { if (SCM_NCELLP (proc)) arg2 = SCM_GLOC_VAL (proc); else arg2 = *scm_lookupcar (SCM_CDR (x), env, 1); } else { arg2 = scm_cons (EVALCAR (proc, env), SCM_EOL); t.lloc = SCM_CDRLOC (arg2); while (SCM_NIMP (proc = SCM_CDR (proc))) { *t.lloc = scm_cons (EVALCAR (proc, env), SCM_EOL); t.lloc = SCM_CDRLOC (*t.lloc); } } type_dispatch: /* The type dispatch code is duplicated here * (c.f. objects.c:scm_mcache_compute_cmethod) since that * cuts down execution time for type dispatch to 50%. */ { long i, n, end, mask; SCM z = SCM_CDDR (x); n = SCM_INUM (SCM_CAR (z)); /* maximum number of specializers */ proc = SCM_CADR (z); if (SCM_NIMP (proc)) { /* Prepare for linear search */ mask = -1; i = 0; end = SCM_VECTOR_LENGTH (proc); } else { /* Compute a hash value */ long hashset = SCM_INUM (proc); long j = n; z = SCM_CDDR (z); mask = SCM_INUM (SCM_CAR (z)); proc = SCM_CADR (z); i = 0; t.arg1 = arg2; if (SCM_NIMP (t.arg1)) do { i += SCM_STRUCT_DATA (scm_class_of (SCM_CAR (t.arg1))) [scm_si_hashsets + hashset]; t.arg1 = SCM_CDR (t.arg1); } while (j-- && SCM_NIMP (t.arg1)); i &= mask; end = i; } /* Search for match */ do { long j = n; z = SCM_VELTS (proc)[i]; t.arg1 = arg2; /* list of arguments */ if (SCM_NIMP (t.arg1)) do { /* More arguments than specifiers => CLASS != ENV */ if (! SCM_EQ_P (scm_class_of (SCM_CAR (t.arg1)), SCM_CAR (z))) goto next_method; t.arg1 = SCM_CDR (t.arg1); z = SCM_CDR (z); } while (j-- && SCM_NIMP (t.arg1)); /* Fewer arguments than specifiers => CAR != ENV */ if (!(SCM_IMP (SCM_CAR (z)) || SCM_CONSP (SCM_CAR (z)))) goto next_method; apply_cmethod: env = EXTEND_ENV (SCM_CAR (SCM_CMETHOD_CODE (z)), arg2, SCM_CMETHOD_ENV (z)); x = SCM_CMETHOD_CODE (z); goto nontoplevel_cdrxbegin; next_method: i = (i + 1) & mask; } while (i != end); z = scm_memoize_method (x, arg2); goto apply_cmethod; } case (SCM_ISYMNUM (SCM_IM_SLOT_REF)): x = SCM_CDR (x); t.arg1 = EVALCAR (x, env); RETURN (SCM_PACK (SCM_STRUCT_DATA (t.arg1) [SCM_INUM (SCM_CADR (x))])) case (SCM_ISYMNUM (SCM_IM_SLOT_SET_X)): x = SCM_CDR (x); t.arg1 = EVALCAR (x, env); x = SCM_CDR (x); proc = SCM_CDR (x); SCM_STRUCT_DATA (t.arg1) [SCM_INUM (SCM_CAR (x))] = SCM_UNPACK (EVALCAR (proc, env)); RETURN (SCM_UNSPECIFIED) case (SCM_ISYMNUM (SCM_IM_NIL_COND)): proc = SCM_CDR (x); while (SCM_NIMP (x = SCM_CDR (proc))) { if (!(SCM_FALSEP (t.arg1 = EVALCAR (proc, env)) || SCM_EQ_P (t.arg1, scm_lisp_nil))) { if (SCM_EQ_P (SCM_CAR (x), SCM_UNSPECIFIED)) RETURN (t.arg1); PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto carloop; } proc = SCM_CDR (x); } x = proc; PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto carloop; case (SCM_ISYMNUM (SCM_IM_NIL_IFY)): x = SCM_CDR (x); RETURN ((SCM_FALSEP (proc = EVALCAR (x, env)) || SCM_NULLP (proc)) ? scm_lisp_nil : proc) case (SCM_ISYMNUM (SCM_IM_T_IFY)): x = SCM_CDR (x); RETURN (SCM_NFALSEP (EVALCAR (x, env)) ? scm_t_lisp : scm_lisp_nil) case (SCM_ISYMNUM (SCM_IM_0_COND)): proc = SCM_CDR (x); while (SCM_NIMP (x = SCM_CDR (proc))) { if (!(SCM_FALSEP (t.arg1 = EVALCAR (proc, env)) || SCM_EQ_P (t.arg1, SCM_INUM0))) { if (SCM_EQ_P (SCM_CAR (x), SCM_UNSPECIFIED)) RETURN (t.arg1); PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto carloop; } proc = SCM_CDR (x); } x = proc; PREP_APPLY (SCM_UNDEFINED, SCM_EOL); goto carloop; case (SCM_ISYMNUM (SCM_IM_0_IFY)): x = SCM_CDR (x); RETURN (SCM_FALSEP (proc = EVALCAR (x, env)) ? SCM_INUM0 : proc) case (SCM_ISYMNUM (SCM_IM_1_IFY)): x = SCM_CDR (x); RETURN (SCM_NFALSEP (EVALCAR (x, env)) ? SCM_MAKINUM (1) : SCM_INUM0) case (SCM_ISYMNUM (SCM_IM_BIND)): x = SCM_CDR (x); t.arg1 = SCM_CAR (x); arg2 = SCM_CDAR (env); while (SCM_NIMP (arg2)) { proc = SCM_GLOC_VAL (SCM_CAR (t.arg1)); SCM_SETCDR (SCM_PACK (SCM_UNPACK (SCM_CAR (t.arg1)) - 1L), SCM_CAR (arg2)); SCM_SETCAR (arg2, proc); t.arg1 = SCM_CDR (t.arg1); arg2 = SCM_CDR (arg2); } t.arg1 = SCM_CAR (x); scm_dynwinds = scm_acons (t.arg1, SCM_CDAR (env), scm_dynwinds); arg2 = x = SCM_CDR (x); while (SCM_NNULLP (arg2 = SCM_CDR (arg2))) { SIDEVAL (SCM_CAR (x), env); x = arg2; } proc = EVALCAR (x, env); scm_dynwinds = SCM_CDR (scm_dynwinds); arg2 = SCM_CDAR (env); while (SCM_NIMP (arg2)) { SCM_SETCDR (SCM_PACK (SCM_UNPACK (SCM_CAR (t.arg1)) - 1L), SCM_CAR (arg2)); t.arg1 = SCM_CDR (t.arg1); arg2 = SCM_CDR (arg2); } RETURN (proc); case (SCM_ISYMNUM (SCM_IM_CALL_WITH_VALUES)): { proc = SCM_CDR (x); x = EVALCAR (proc, env); proc = SCM_CDR (proc); proc = EVALCAR (proc, env); t.arg1 = SCM_APPLY (x, SCM_EOL, SCM_EOL); if (SCM_VALUESP (t.arg1)) t.arg1 = scm_struct_ref (t.arg1, SCM_INUM0); else t.arg1 = scm_cons (t.arg1, SCM_EOL); if (SCM_CLOSUREP (proc)) { PREP_APPLY (proc, t.arg1); goto apply_closure; } return SCM_APPLY (proc, t.arg1, SCM_EOL); } default: goto badfun; } default: proc = x; badfun: /* scm_everr (x, env,...) */ scm_misc_error (NULL, "Wrong type to apply: ~S", SCM_LIST1 (proc)); case scm_tc7_vector: case scm_tc7_wvect: #ifdef HAVE_ARRAYS case scm_tc7_bvect: case scm_tc7_byvect: case scm_tc7_svect: case scm_tc7_ivect: case scm_tc7_uvect: case scm_tc7_fvect: case scm_tc7_dvect: case scm_tc7_cvect: #ifdef HAVE_LONG_LONGS case scm_tc7_llvect: #endif #endif case scm_tc7_string: case scm_tc7_substring: case scm_tc7_smob: case scm_tcs_closures: case scm_tc7_cclo: case scm_tc7_pws: case scm_tcs_subrs: RETURN (x); #ifdef MEMOIZE_LOCALS case SCM_BIT8(SCM_ILOC00): proc = *scm_ilookup (SCM_CAR (x), env); SCM_ASRTGO (SCM_NIMP (proc), badfun); #ifndef SCM_RECKLESS #ifdef SCM_CAUTIOUS goto checkargs; #endif #endif break; #endif /* ifdef MEMOIZE_LOCALS */ case scm_tcs_cons_gloc: { scm_t_bits vcell = SCM_STRUCT_VTABLE_DATA (x) [scm_vtable_index_vcell]; if (vcell == 0) { /* This is a struct implanted in the code, not a gloc. */ RETURN (x); } else { proc = SCM_GLOC_VAL (SCM_CAR (x)); SCM_ASRTGO (SCM_NIMP (proc), badfun); #ifndef SCM_RECKLESS #ifdef SCM_CAUTIOUS goto checkargs; #endif #endif } break; } case scm_tcs_cons_nimcar: orig_sym = SCM_CAR (x); if (SCM_SYMBOLP (orig_sym)) { #ifdef USE_THREADS t.lloc = scm_lookupcar1 (x, env, 1); if (t.lloc == NULL) { /* we have lost the race, start again. */ goto dispatch; } proc = *t.lloc; #else proc = *scm_lookupcar (x, env, 1); #endif if (SCM_IMP (proc)) { SCM_SETCAR (x, orig_sym); /* Undo memoizing effect of lookupcar */ goto badfun; } if (SCM_MACROP (proc)) { SCM_SETCAR (x, orig_sym); /* Undo memoizing effect of lookupcar */ handle_a_macro: #ifdef DEVAL /* Set a flag during macro expansion so that macro application frames can be deleted from the backtrace. */ SCM_SET_MACROEXP (debug); #endif t.arg1 = SCM_APPLY (SCM_MACRO_CODE (proc), x, scm_cons (env, scm_listofnull)); #ifdef DEVAL SCM_CLEAR_MACROEXP (debug); #endif switch (SCM_MACRO_TYPE (proc)) { case 2: if (scm_ilength (t.arg1) <= 0) t.arg1 = scm_cons2 (SCM_IM_BEGIN, t.arg1, SCM_EOL); #ifdef DEVAL if (!SCM_CLOSUREP (SCM_MACRO_CODE (proc))) { SCM_DEFER_INTS; SCM_SETCAR (x, SCM_CAR (t.arg1)); SCM_SETCDR (x, SCM_CDR (t.arg1)); SCM_ALLOW_INTS; goto dispatch; } /* Prevent memoizing of debug info expression. */ debug.info->e.exp = scm_cons_source (debug.info->e.exp, SCM_CAR (x), SCM_CDR (x)); #endif SCM_DEFER_INTS; SCM_SETCAR (x, SCM_CAR (t.arg1)); SCM_SETCDR (x, SCM_CDR (t.arg1)); SCM_ALLOW_INTS; goto loopnoap; case 1: if (SCM_NIMP (x = t.arg1)) goto loopnoap; case 0: RETURN (t.arg1); } } } else proc = SCM_CEVAL (SCM_CAR (x), env); SCM_ASRTGO (!SCM_IMP (proc), badfun); #ifndef SCM_RECKLESS #ifdef SCM_CAUTIOUS checkargs: #endif if (SCM_CLOSUREP (proc)) { arg2 = SCM_CLOSURE_FORMALS (proc); t.arg1 = SCM_CDR (x); while (!SCM_NULLP (arg2)) { if (!SCM_CONSP (arg2)) goto evapply; if (SCM_IMP (t.arg1)) goto umwrongnumargs; arg2 = SCM_CDR (arg2); t.arg1 = SCM_CDR (t.arg1); } if (!SCM_NULLP (t.arg1)) goto umwrongnumargs; } else if (SCM_MACROP (proc)) goto handle_a_macro; #endif } evapply: PREP_APPLY (proc, SCM_EOL); if (SCM_NULLP (SCM_CDR (x))) { ENTER_APPLY; evap0: switch (SCM_TYP7 (proc)) { /* no arguments given */ case scm_tc7_subr_0: RETURN (SCM_SUBRF (proc) ()); case scm_tc7_subr_1o: RETURN (SCM_SUBRF (proc) (SCM_UNDEFINED)); case scm_tc7_lsubr: RETURN (SCM_SUBRF (proc) (SCM_EOL)); case scm_tc7_rpsubr: RETURN (SCM_BOOL_T); case scm_tc7_asubr: RETURN (SCM_SUBRF (proc) (SCM_UNDEFINED, SCM_UNDEFINED)); case scm_tc7_smob: if (!SCM_SMOB_APPLICABLE_P (proc)) goto badfun; RETURN (SCM_SMOB_APPLY_0 (proc)); case scm_tc7_cclo: t.arg1 = proc; proc = SCM_CCLO_SUBR (proc); #ifdef DEVAL debug.info->a.proc = proc; debug.info->a.args = scm_cons (t.arg1, SCM_EOL); #endif goto evap1; case scm_tc7_pws: proc = SCM_PROCEDURE (proc); #ifdef DEVAL debug.info->a.proc = proc; #endif if (!SCM_CLOSUREP (proc)) goto evap0; if (scm_badformalsp (proc, 0)) goto umwrongnumargs; case scm_tcs_closures: x = SCM_CODE (proc); env = EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), SCM_EOL, SCM_ENV (proc)); goto nontoplevel_cdrxbegin; case scm_tcs_cons_gloc: /* really structs, not glocs */ if (SCM_OBJ_CLASS_FLAGS (proc) & SCM_CLASSF_PURE_GENERIC) { x = SCM_ENTITY_PROCEDURE (proc); arg2 = SCM_EOL; goto type_dispatch; } else if (!SCM_I_OPERATORP (proc)) goto badfun; else { t.arg1 = proc; proc = (SCM_I_ENTITYP (proc) ? SCM_ENTITY_PROCEDURE (proc) : SCM_OPERATOR_PROCEDURE (proc)); #ifdef DEVAL debug.info->a.proc = proc; debug.info->a.args = scm_cons (t.arg1, SCM_EOL); #endif if (SCM_NIMP (proc)) goto evap1; else goto badfun; } case scm_tc7_subr_1: case scm_tc7_subr_2: case scm_tc7_subr_2o: case scm_tc7_cxr: case scm_tc7_subr_3: case scm_tc7_lsubr_2: umwrongnumargs: unmemocar (x, env); wrongnumargs: /* scm_everr (x, env,...) */ scm_wrong_num_args (proc); default: /* handle macros here */ goto badfun; } } /* must handle macros by here */ x = SCM_CDR (x); #ifdef SCM_CAUTIOUS if (SCM_IMP (x)) goto wrongnumargs; else if (SCM_CONSP (x)) { if (SCM_IMP (SCM_CAR (x))) t.arg1 = SCM_EVALIM (SCM_CAR (x), env); else t.arg1 = EVALCELLCAR (x, env); } else if (SCM_TYP3 (x) == scm_tc3_cons_gloc) { scm_t_bits vcell = SCM_STRUCT_VTABLE_DATA (x) [scm_vtable_index_vcell]; if (vcell == 0) t.arg1 = SCM_CAR (x); /* struct planted in code */ else t.arg1 = SCM_GLOC_VAL (SCM_CAR (x)); } else goto wrongnumargs; #else t.arg1 = EVALCAR (x, env); #endif #ifdef DEVAL debug.info->a.args = scm_cons (t.arg1, SCM_EOL); #endif x = SCM_CDR (x); if (SCM_NULLP (x)) { ENTER_APPLY; evap1: switch (SCM_TYP7 (proc)) { /* have one argument in t.arg1 */ case scm_tc7_subr_2o: RETURN (SCM_SUBRF (proc) (t.arg1, SCM_UNDEFINED)); case scm_tc7_subr_1: case scm_tc7_subr_1o: RETURN (SCM_SUBRF (proc) (t.arg1)); case scm_tc7_cxr: if (SCM_SUBRF (proc)) { if (SCM_INUMP (t.arg1)) { RETURN (scm_make_real (SCM_DSUBRF (proc) ((double) SCM_INUM (t.arg1)))); } SCM_ASRTGO (SCM_NIMP (t.arg1), floerr); if (SCM_REALP (t.arg1)) { RETURN (scm_make_real (SCM_DSUBRF (proc) (SCM_REAL_VALUE (t.arg1)))); } #ifdef SCM_BIGDIG if (SCM_BIGP (t.arg1)) { RETURN (scm_make_real (SCM_DSUBRF (proc) (scm_i_big2dbl (t.arg1)))); } #endif floerr: SCM_WTA_DISPATCH_1 (*SCM_SUBR_GENERIC (proc), t.arg1, SCM_ARG1, SCM_SYMBOL_CHARS (SCM_SNAME (proc))); } proc = SCM_SNAME (proc); { char *chrs = SCM_SYMBOL_CHARS (proc) + SCM_SYMBOL_LENGTH (proc) - 1; while ('c' != *--chrs) { SCM_ASSERT (SCM_CONSP (t.arg1), t.arg1, SCM_ARG1, SCM_SYMBOL_CHARS (proc)); t.arg1 = ('a' == *chrs) ? SCM_CAR (t.arg1) : SCM_CDR (t.arg1); } RETURN (t.arg1); } case scm_tc7_rpsubr: RETURN (SCM_BOOL_T); case scm_tc7_asubr: RETURN (SCM_SUBRF (proc) (t.arg1, SCM_UNDEFINED)); case scm_tc7_lsubr: #ifdef DEVAL RETURN (SCM_SUBRF (proc) (debug.info->a.args)) #else RETURN (SCM_SUBRF (proc) (scm_cons (t.arg1, SCM_EOL))); #endif case scm_tc7_smob: if (!SCM_SMOB_APPLICABLE_P (proc)) goto badfun; RETURN (SCM_SMOB_APPLY_1 (proc, t.arg1)); case scm_tc7_cclo: arg2 = t.arg1; t.arg1 = proc; proc = SCM_CCLO_SUBR (proc); #ifdef DEVAL debug.info->a.args = scm_cons (t.arg1, debug.info->a.args); debug.info->a.proc = proc; #endif goto evap2; case scm_tc7_pws: proc = SCM_PROCEDURE (proc); #ifdef DEVAL debug.info->a.proc = proc; #endif if (!SCM_CLOSUREP (proc)) goto evap1; if (scm_badformalsp (proc, 1)) goto umwrongnumargs; case scm_tcs_closures: /* clos1: */ x = SCM_CODE (proc); #ifdef DEVAL env = EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), debug.info->a.args, SCM_ENV (proc)); #else env = EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), scm_cons (t.arg1, SCM_EOL), SCM_ENV (proc)); #endif goto nontoplevel_cdrxbegin; case scm_tcs_cons_gloc: /* really structs, not glocs */ if (SCM_OBJ_CLASS_FLAGS (proc) & SCM_CLASSF_PURE_GENERIC) { x = SCM_ENTITY_PROCEDURE (proc); #ifdef DEVAL arg2 = debug.info->a.args; #else arg2 = scm_cons (t.arg1, SCM_EOL); #endif goto type_dispatch; } else if (!SCM_I_OPERATORP (proc)) goto badfun; else { arg2 = t.arg1; t.arg1 = proc; proc = (SCM_I_ENTITYP (proc) ? SCM_ENTITY_PROCEDURE (proc) : SCM_OPERATOR_PROCEDURE (proc)); #ifdef DEVAL debug.info->a.args = scm_cons (t.arg1, debug.info->a.args); debug.info->a.proc = proc; #endif if (SCM_NIMP (proc)) goto evap2; else goto badfun; } case scm_tc7_subr_2: case scm_tc7_subr_0: case scm_tc7_subr_3: case scm_tc7_lsubr_2: goto wrongnumargs; default: goto badfun; } } #ifdef SCM_CAUTIOUS if (SCM_IMP (x)) goto wrongnumargs; else if (SCM_CONSP (x)) { if (SCM_IMP (SCM_CAR (x))) arg2 = SCM_EVALIM (SCM_CAR (x), env); else arg2 = EVALCELLCAR (x, env); } else if (SCM_TYP3 (x) == scm_tc3_cons_gloc) { scm_t_bits vcell = SCM_STRUCT_VTABLE_DATA (x) [scm_vtable_index_vcell]; if (vcell == 0) arg2 = SCM_CAR (x); /* struct planted in code */ else arg2 = SCM_GLOC_VAL (SCM_CAR (x)); } else goto wrongnumargs; #else arg2 = EVALCAR (x, env); #endif { /* have two or more arguments */ #ifdef DEVAL debug.info->a.args = scm_cons2 (t.arg1, arg2, SCM_EOL); #endif x = SCM_CDR (x); if (SCM_NULLP (x)) { ENTER_APPLY; evap2: switch (SCM_TYP7 (proc)) { /* have two arguments */ case scm_tc7_subr_2: case scm_tc7_subr_2o: RETURN (SCM_SUBRF (proc) (t.arg1, arg2)); case scm_tc7_lsubr: #ifdef DEVAL RETURN (SCM_SUBRF (proc) (debug.info->a.args)) #else RETURN (SCM_SUBRF (proc) (scm_cons2 (t.arg1, arg2, SCM_EOL))); #endif case scm_tc7_lsubr_2: RETURN (SCM_SUBRF (proc) (t.arg1, arg2, SCM_EOL)); case scm_tc7_rpsubr: case scm_tc7_asubr: RETURN (SCM_SUBRF (proc) (t.arg1, arg2)); case scm_tc7_smob: if (!SCM_SMOB_APPLICABLE_P (proc)) goto badfun; RETURN (SCM_SMOB_APPLY_2 (proc, t.arg1, arg2)); cclon: case scm_tc7_cclo: #ifdef DEVAL RETURN (SCM_APPLY (SCM_CCLO_SUBR (proc), scm_cons (proc, debug.info->a.args), SCM_EOL)); #else RETURN (SCM_APPLY (SCM_CCLO_SUBR (proc), scm_cons2 (proc, t.arg1, scm_cons (arg2, scm_eval_args (x, env, proc))), SCM_EOL)); #endif case scm_tcs_cons_gloc: /* really structs, not glocs */ if (SCM_OBJ_CLASS_FLAGS (proc) & SCM_CLASSF_PURE_GENERIC) { x = SCM_ENTITY_PROCEDURE (proc); #ifdef DEVAL arg2 = debug.info->a.args; #else arg2 = scm_cons2 (t.arg1, arg2, SCM_EOL); #endif goto type_dispatch; } else if (!SCM_I_OPERATORP (proc)) goto badfun; else { operatorn: #ifdef DEVAL RETURN (SCM_APPLY (SCM_I_ENTITYP (proc) ? SCM_ENTITY_PROCEDURE (proc) : SCM_OPERATOR_PROCEDURE (proc), scm_cons (proc, debug.info->a.args), SCM_EOL)); #else RETURN (SCM_APPLY (SCM_I_ENTITYP (proc) ? SCM_ENTITY_PROCEDURE (proc) : SCM_OPERATOR_PROCEDURE (proc), scm_cons2 (proc, t.arg1, scm_cons (arg2, scm_eval_args (x, env, proc))), SCM_EOL)); #endif } case scm_tc7_subr_0: case scm_tc7_cxr: case scm_tc7_subr_1o: case scm_tc7_subr_1: case scm_tc7_subr_3: goto wrongnumargs; default: goto badfun; case scm_tc7_pws: proc = SCM_PROCEDURE (proc); #ifdef DEVAL debug.info->a.proc = proc; #endif if (!SCM_CLOSUREP (proc)) goto evap2; if (scm_badformalsp (proc, 2)) goto umwrongnumargs; case scm_tcs_closures: /* clos2: */ #ifdef DEVAL env = EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), debug.info->a.args, SCM_ENV (proc)); #else env = EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), scm_cons2 (t.arg1, arg2, SCM_EOL), SCM_ENV (proc)); #endif x = SCM_CODE (proc); goto nontoplevel_cdrxbegin; } } #ifdef SCM_CAUTIOUS if (SCM_IMP (x) || SCM_NECONSP (x)) goto wrongnumargs; #endif #ifdef DEVAL debug.info->a.args = scm_cons2 (t.arg1, arg2, scm_deval_args (x, env, proc, SCM_CDRLOC (SCM_CDR (debug.info->a.args)))); #endif ENTER_APPLY; evap3: switch (SCM_TYP7 (proc)) { /* have 3 or more arguments */ #ifdef DEVAL case scm_tc7_subr_3: SCM_ASRTGO (SCM_NULLP (SCM_CDR (x)), wrongnumargs); RETURN (SCM_SUBRF (proc) (t.arg1, arg2, SCM_CADDR (debug.info->a.args))); case scm_tc7_asubr: #ifdef BUILTIN_RPASUBR t.arg1 = SCM_SUBRF(proc)(t.arg1, arg2); arg2 = SCM_CDR (SCM_CDR (debug.info->a.args)); do { t.arg1 = SCM_SUBRF(proc)(t.arg1, SCM_CAR (arg2)); arg2 = SCM_CDR (arg2); } while (SCM_NIMP (arg2)); RETURN (t.arg1) #endif /* BUILTIN_RPASUBR */ case scm_tc7_rpsubr: #ifdef BUILTIN_RPASUBR if (SCM_FALSEP (SCM_SUBRF (proc) (t.arg1, arg2))) RETURN (SCM_BOOL_F) t.arg1 = SCM_CDR (SCM_CDR (debug.info->a.args)); do { if (SCM_FALSEP (SCM_SUBRF (proc) (arg2, SCM_CAR (t.arg1)))) RETURN (SCM_BOOL_F) arg2 = SCM_CAR (t.arg1); t.arg1 = SCM_CDR (t.arg1); } while (SCM_NIMP (t.arg1)); RETURN (SCM_BOOL_T) #else /* BUILTIN_RPASUBR */ RETURN (SCM_APPLY (proc, t.arg1, scm_acons (arg2, SCM_CDR (SCM_CDR (debug.info->a.args)), SCM_EOL))) #endif /* BUILTIN_RPASUBR */ case scm_tc7_lsubr_2: RETURN (SCM_SUBRF (proc) (t.arg1, arg2, SCM_CDR (SCM_CDR (debug.info->a.args)))) case scm_tc7_lsubr: RETURN (SCM_SUBRF (proc) (debug.info->a.args)) case scm_tc7_smob: if (!SCM_SMOB_APPLICABLE_P (proc)) goto badfun; RETURN (SCM_SMOB_APPLY_3 (proc, t.arg1, arg2, SCM_CDDR (debug.info->a.args))); case scm_tc7_cclo: goto cclon; case scm_tc7_pws: proc = SCM_PROCEDURE (proc); debug.info->a.proc = proc; if (!SCM_CLOSUREP (proc)) goto evap3; if (scm_badargsp (SCM_CLOSURE_FORMALS (proc), debug.info->a.args)) goto umwrongnumargs; case scm_tcs_closures: SCM_SET_ARGSREADY (debug); env = EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), debug.info->a.args, SCM_ENV (proc)); x = SCM_CODE (proc); goto nontoplevel_cdrxbegin; #else /* DEVAL */ case scm_tc7_subr_3: SCM_ASRTGO (SCM_NULLP (SCM_CDR (x)), wrongnumargs); RETURN (SCM_SUBRF (proc) (t.arg1, arg2, EVALCAR (x, env))); case scm_tc7_asubr: #ifdef BUILTIN_RPASUBR t.arg1 = SCM_SUBRF (proc) (t.arg1, arg2); do { t.arg1 = SCM_SUBRF(proc)(t.arg1, EVALCAR(x, env)); x = SCM_CDR(x); } while (SCM_NIMP (x)); RETURN (t.arg1) #endif /* BUILTIN_RPASUBR */ case scm_tc7_rpsubr: #ifdef BUILTIN_RPASUBR if (SCM_FALSEP (SCM_SUBRF (proc) (t.arg1, arg2))) RETURN (SCM_BOOL_F) do { t.arg1 = EVALCAR (x, env); if (SCM_FALSEP (SCM_SUBRF (proc) (arg2, t.arg1))) RETURN (SCM_BOOL_F) arg2 = t.arg1; x = SCM_CDR (x); } while (SCM_NIMP (x)); RETURN (SCM_BOOL_T) #else /* BUILTIN_RPASUBR */ RETURN (SCM_APPLY (proc, t.arg1, scm_acons (arg2, scm_eval_args (x, env, proc), SCM_EOL))); #endif /* BUILTIN_RPASUBR */ case scm_tc7_lsubr_2: RETURN (SCM_SUBRF (proc) (t.arg1, arg2, scm_eval_args (x, env, proc))); case scm_tc7_lsubr: RETURN (SCM_SUBRF (proc) (scm_cons2 (t.arg1, arg2, scm_eval_args (x, env, proc)))); case scm_tc7_smob: if (!SCM_SMOB_APPLICABLE_P (proc)) goto badfun; RETURN (SCM_SMOB_APPLY_3 (proc, t.arg1, arg2, scm_eval_args (x, env, proc))); case scm_tc7_cclo: goto cclon; case scm_tc7_pws: proc = SCM_PROCEDURE (proc); if (!SCM_CLOSUREP (proc)) goto evap3; { SCM formals = SCM_CLOSURE_FORMALS (proc); if (SCM_NULLP (formals) || (SCM_CONSP (formals) && (SCM_NULLP (SCM_CDR (formals)) || (SCM_CONSP (SCM_CDR (formals)) && scm_badargsp (SCM_CDDR (formals), x))))) goto umwrongnumargs; } case scm_tcs_closures: #ifdef DEVAL SCM_SET_ARGSREADY (debug); #endif env = EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), scm_cons2 (t.arg1, arg2, scm_eval_args (x, env, proc)), SCM_ENV (proc)); x = SCM_CODE (proc); goto nontoplevel_cdrxbegin; #endif /* DEVAL */ case scm_tcs_cons_gloc: /* really structs, not glocs */ if (SCM_OBJ_CLASS_FLAGS (proc) & SCM_CLASSF_PURE_GENERIC) { #ifdef DEVAL arg2 = debug.info->a.args; #else arg2 = scm_cons2 (t.arg1, arg2, scm_eval_args (x, env, proc)); #endif x = SCM_ENTITY_PROCEDURE (proc); goto type_dispatch; } else if (!SCM_I_OPERATORP (proc)) goto badfun; else goto operatorn; case scm_tc7_subr_2: case scm_tc7_subr_1o: case scm_tc7_subr_2o: case scm_tc7_subr_0: case scm_tc7_cxr: case scm_tc7_subr_1: goto wrongnumargs; default: goto badfun; } } #ifdef DEVAL exit: if (CHECK_EXIT && SCM_TRAPS_P) if (SCM_EXIT_FRAME_P || (SCM_TRACE_P && SCM_TRACED_FRAME_P (debug))) { SCM_CLEAR_TRACED_FRAME (debug); if (SCM_CHEAPTRAPS_P) t.arg1 = scm_make_debugobj (&debug); else { int first; SCM val = scm_make_continuation (&first); if (first) t.arg1 = val; else { proc = val; goto ret; } } scm_ithrow (scm_sym_exit_frame, scm_cons2 (t.arg1, proc, SCM_EOL), 0); } ret: scm_last_debug_frame = debug.prev; return proc; #endif } /* SECTION: This code is compiled once. */ #ifndef DEVAL /* This code processes the arguments to apply: (apply PROC ARG1 ... ARGS) Given a list (ARG1 ... ARGS), this function conses the ARG1 ... arguments onto the front of ARGS, and returns the resulting list. Note that ARGS is a list; thus, the argument to this function is a list whose last element is a list. Apply calls this function, and applies PROC to the elements of the result. apply:nconc2last takes care of building the list of arguments, given (ARG1 ... ARGS). Rather than do new consing, apply:nconc2last destroys its argument. On that topic, this code came into my care with the following beautifully cryptic comment on that topic: "This will only screw you if you do (scm_apply scm_apply '( ... ))" If you know what they're referring to, send me a patch to this comment. */ SCM_DEFINE (scm_nconc2last, "apply:nconc2last", 1, 0, 0, (SCM lst), "Given a list (@var{arg1} @dots{} @var{args}), this function\n" "conses the @var{arg1} @dots{} arguments onto the front of\n" "@var{args}, and returns the resulting list. Note that\n" "@var{args} is a list; thus, the argument to this function is\n" "a list whose last element is a list.\n" "Note: Rather than do new consing, @code{apply:nconc2last}\n" "destroys its argument, so use with care.") #define FUNC_NAME s_scm_nconc2last { SCM *lloc; SCM_VALIDATE_NONEMPTYLIST (1,lst); lloc = &lst; while (SCM_NNULLP (SCM_CDR (*lloc))) lloc = SCM_CDRLOC (*lloc); SCM_ASSERT (scm_ilength (SCM_CAR (*lloc)) >= 0, lst, SCM_ARG1, FUNC_NAME); *lloc = SCM_CAR (*lloc); return lst; } #undef FUNC_NAME #endif /* !DEVAL */ /* SECTION: When DEVAL is defined this code yields scm_dapply. * It is compiled twice. */ #if 0 SCM scm_apply (SCM proc, SCM arg1, SCM args) {} #endif #if 0 SCM scm_dapply (SCM proc, SCM arg1, SCM args) { /* empty */ } #endif /* Apply a function to a list of arguments. This function is exported to the Scheme level as taking two required arguments and a tail argument, as if it were: (lambda (proc arg1 . args) ...) Thus, if you just have a list of arguments to pass to a procedure, pass the list as ARG1, and '() for ARGS. If you have some fixed args, pass the first as ARG1, then cons any remaining fixed args onto the front of your argument list, and pass that as ARGS. */ SCM SCM_APPLY (SCM proc, SCM arg1, SCM args) { #ifdef DEBUG_EXTENSIONS #ifdef DEVAL scm_t_debug_frame debug; scm_t_debug_info debug_vect_body; debug.prev = scm_last_debug_frame; debug.status = SCM_APPLYFRAME; debug.vect = &debug_vect_body; debug.vect[0].a.proc = proc; debug.vect[0].a.args = SCM_EOL; scm_last_debug_frame = &debug; #else if (SCM_DEBUGGINGP) return scm_dapply (proc, arg1, args); #endif #endif SCM_ASRTGO (SCM_NIMP (proc), badproc); /* If ARGS is the empty list, then we're calling apply with only two arguments --- ARG1 is the list of arguments for PROC. Whatever the case, futz with things so that ARG1 is the first argument to give to PROC (or SCM_UNDEFINED if no args), and ARGS contains the rest. Setting the debug apply frame args this way is pretty messy. Perhaps we should store arg1 and args directly in the frame as received, and let scm_frame_arguments unpack them, because that's a relatively rare operation. This works for now; if the Guile developer archives are still around, see Mikael's post of 11-Apr-97. */ if (SCM_NULLP (args)) { if (SCM_NULLP (arg1)) { arg1 = SCM_UNDEFINED; #ifdef DEVAL debug.vect[0].a.args = SCM_EOL; #endif } else { #ifdef DEVAL debug.vect[0].a.args = arg1; #endif args = SCM_CDR (arg1); arg1 = SCM_CAR (arg1); } } else { args = scm_nconc2last (args); #ifdef DEVAL debug.vect[0].a.args = scm_cons (arg1, args); #endif } #ifdef DEVAL if (SCM_ENTER_FRAME_P && SCM_TRAPS_P) { SCM tmp; if (SCM_CHEAPTRAPS_P) tmp = scm_make_debugobj (&debug); else { int first; tmp = scm_make_continuation (&first); if (!first) goto entap; } scm_ithrow (scm_sym_enter_frame, scm_cons (tmp, SCM_EOL), 0); } entap: ENTER_APPLY; #endif tail: switch (SCM_TYP7 (proc)) { case scm_tc7_subr_2o: args = SCM_NULLP (args) ? SCM_UNDEFINED : SCM_CAR (args); RETURN (SCM_SUBRF (proc) (arg1, args)) case scm_tc7_subr_2: SCM_ASRTGO (SCM_NNULLP (args) && SCM_NULLP (SCM_CDR (args)), wrongnumargs); args = SCM_CAR (args); RETURN (SCM_SUBRF (proc) (arg1, args)) case scm_tc7_subr_0: SCM_ASRTGO (SCM_UNBNDP (arg1), wrongnumargs); RETURN (SCM_SUBRF (proc) ()) case scm_tc7_subr_1: SCM_ASRTGO (!SCM_UNBNDP (arg1), wrongnumargs); case scm_tc7_subr_1o: SCM_ASRTGO (SCM_NULLP (args), wrongnumargs); RETURN (SCM_SUBRF (proc) (arg1)) case scm_tc7_cxr: SCM_ASRTGO (!SCM_UNBNDP (arg1) && SCM_NULLP (args), wrongnumargs); if (SCM_SUBRF (proc)) { if (SCM_INUMP (arg1)) { RETURN (scm_make_real (SCM_DSUBRF (proc) ((double) SCM_INUM (arg1)))); } SCM_ASRTGO (SCM_NIMP (arg1), floerr); if (SCM_REALP (arg1)) { RETURN (scm_make_real (SCM_DSUBRF (proc) (SCM_REAL_VALUE (arg1)))); } #ifdef SCM_BIGDIG if (SCM_BIGP (arg1)) RETURN (scm_make_real (SCM_DSUBRF (proc) (scm_i_big2dbl (arg1)))) #endif floerr: SCM_WTA_DISPATCH_1 (*SCM_SUBR_GENERIC (proc), arg1, SCM_ARG1, SCM_SYMBOL_CHARS (SCM_SNAME (proc))); } proc = SCM_SNAME (proc); { char *chrs = SCM_SYMBOL_CHARS (proc) + SCM_SYMBOL_LENGTH (proc) - 1; while ('c' != *--chrs) { SCM_ASSERT (SCM_CONSP (arg1), arg1, SCM_ARG1, SCM_SYMBOL_CHARS (proc)); arg1 = ('a' == *chrs) ? SCM_CAR (arg1) : SCM_CDR (arg1); } RETURN (arg1) } case scm_tc7_subr_3: SCM_ASRTGO (SCM_NNULLP (args) && SCM_NNULLP (SCM_CDR (args)) && SCM_NULLP (SCM_CDDR (args)), wrongnumargs); RETURN (SCM_SUBRF (proc) (arg1, SCM_CAR (args), SCM_CAR (SCM_CDR (args)))) case scm_tc7_lsubr: #ifdef DEVAL RETURN (SCM_SUBRF (proc) (SCM_UNBNDP (arg1) ? SCM_EOL : debug.vect[0].a.args)) #else RETURN (SCM_SUBRF (proc) (SCM_UNBNDP (arg1) ? SCM_EOL : scm_cons (arg1, args))) #endif case scm_tc7_lsubr_2: SCM_ASRTGO (SCM_CONSP (args), wrongnumargs); RETURN (SCM_SUBRF (proc) (arg1, SCM_CAR (args), SCM_CDR (args))) case scm_tc7_asubr: if (SCM_NULLP (args)) RETURN (SCM_SUBRF (proc) (arg1, SCM_UNDEFINED)) while (SCM_NIMP (args)) { SCM_ASSERT (SCM_CONSP (args), args, SCM_ARG2, "apply"); arg1 = SCM_SUBRF (proc) (arg1, SCM_CAR (args)); args = SCM_CDR (args); } RETURN (arg1); case scm_tc7_rpsubr: if (SCM_NULLP (args)) RETURN (SCM_BOOL_T); while (SCM_NIMP (args)) { SCM_ASSERT (SCM_CONSP (args), args, SCM_ARG2, "apply"); if (SCM_FALSEP (SCM_SUBRF (proc) (arg1, SCM_CAR (args)))) RETURN (SCM_BOOL_F); arg1 = SCM_CAR (args); args = SCM_CDR (args); } RETURN (SCM_BOOL_T); case scm_tcs_closures: #ifdef DEVAL arg1 = (SCM_UNBNDP (arg1) ? SCM_EOL : debug.vect[0].a.args); #else arg1 = (SCM_UNBNDP (arg1) ? SCM_EOL : scm_cons (arg1, args)); #endif #ifndef SCM_RECKLESS if (scm_badargsp (SCM_CLOSURE_FORMALS (proc), arg1)) goto wrongnumargs; #endif /* Copy argument list */ if (SCM_IMP (arg1)) args = arg1; else { SCM tl = args = scm_cons (SCM_CAR (arg1), SCM_UNSPECIFIED); while (arg1 = SCM_CDR (arg1), SCM_CONSP (arg1)) { SCM_SETCDR (tl, scm_cons (SCM_CAR (arg1), SCM_UNSPECIFIED)); tl = SCM_CDR (tl); } SCM_SETCDR (tl, arg1); } args = EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), args, SCM_ENV (proc)); proc = SCM_CDR (SCM_CODE (proc)); again: arg1 = proc; while (SCM_NNULLP (arg1 = SCM_CDR (arg1))) { if (SCM_IMP (SCM_CAR (proc))) { if (SCM_ISYMP (SCM_CAR (proc))) { proc = scm_m_expand_body (proc, args); goto again; } else SCM_VALIDATE_NON_EMPTY_COMBINATION (SCM_CAR (proc)); } else SCM_CEVAL (SCM_CAR (proc), args); proc = arg1; } RETURN (EVALCAR (proc, args)); case scm_tc7_smob: if (!SCM_SMOB_APPLICABLE_P (proc)) goto badproc; if (SCM_UNBNDP (arg1)) RETURN (SCM_SMOB_APPLY_0 (proc)) else if (SCM_NULLP (args)) RETURN (SCM_SMOB_APPLY_1 (proc, arg1)) else if (SCM_NULLP (SCM_CDR (args))) RETURN (SCM_SMOB_APPLY_2 (proc, arg1, SCM_CAR (args))) else RETURN (SCM_SMOB_APPLY_3 (proc, arg1, SCM_CAR (args), SCM_CDR (args))); case scm_tc7_cclo: #ifdef DEVAL args = (SCM_UNBNDP(arg1) ? SCM_EOL : debug.vect[0].a.args); arg1 = proc; proc = SCM_CCLO_SUBR (proc); debug.vect[0].a.proc = proc; debug.vect[0].a.args = scm_cons (arg1, args); #else args = (SCM_UNBNDP(arg1) ? SCM_EOL : scm_cons (arg1, args)); arg1 = proc; proc = SCM_CCLO_SUBR (proc); #endif goto tail; case scm_tc7_pws: proc = SCM_PROCEDURE (proc); #ifdef DEVAL debug.vect[0].a.proc = proc; #endif goto tail; case scm_tcs_cons_gloc: /* really structs, not glocs */ if (SCM_OBJ_CLASS_FLAGS (proc) & SCM_CLASSF_PURE_GENERIC) { #ifdef DEVAL args = (SCM_UNBNDP(arg1) ? SCM_EOL : debug.vect[0].a.args); #else args = (SCM_UNBNDP(arg1) ? SCM_EOL : scm_cons (arg1, args)); #endif RETURN (scm_apply_generic (proc, args)); } else if (!SCM_I_OPERATORP (proc)) goto badproc; else { #ifdef DEVAL args = (SCM_UNBNDP(arg1) ? SCM_EOL : debug.vect[0].a.args); #else args = (SCM_UNBNDP(arg1) ? SCM_EOL : scm_cons (arg1, args)); #endif arg1 = proc; proc = (SCM_I_ENTITYP (proc) ? SCM_ENTITY_PROCEDURE (proc) : SCM_OPERATOR_PROCEDURE (proc)); #ifdef DEVAL debug.vect[0].a.proc = proc; debug.vect[0].a.args = scm_cons (arg1, args); #endif if (SCM_NIMP (proc)) goto tail; else goto badproc; } wrongnumargs: scm_wrong_num_args (proc); default: badproc: scm_wrong_type_arg ("apply", SCM_ARG1, proc); RETURN (arg1); } #ifdef DEVAL exit: if (CHECK_EXIT && SCM_TRAPS_P) if (SCM_EXIT_FRAME_P || (SCM_TRACE_P && SCM_TRACED_FRAME_P (debug))) { SCM_CLEAR_TRACED_FRAME (debug); if (SCM_CHEAPTRAPS_P) arg1 = scm_make_debugobj (&debug); else { int first; SCM val = scm_make_continuation (&first); if (first) arg1 = val; else { proc = val; goto ret; } } scm_ithrow (scm_sym_exit_frame, scm_cons2 (arg1, proc, SCM_EOL), 0); } ret: scm_last_debug_frame = debug.prev; return proc; #endif } /* SECTION: The rest of this file is only read once. */ #ifndef DEVAL /* Typechecking for multi-argument MAP and FOR-EACH. Verify that each element of the vector ARGV, except for the first, is a proper list whose length is LEN. Attribute errors to WHO, and claim that the i'th element of ARGV is WHO's i+2'th argument. */ static inline void check_map_args (SCM argv, long len, SCM gf, SCM proc, SCM args, const char *who) { SCM *ve = SCM_VELTS (argv); long i; for (i = SCM_VECTOR_LENGTH (argv) - 1; i >= 1; i--) { long elt_len = scm_ilength (ve[i]); if (elt_len < 0) { if (gf) scm_apply_generic (gf, scm_cons (proc, args)); else scm_wrong_type_arg (who, i + 2, ve[i]); } if (elt_len != len) scm_out_of_range (who, ve[i]); } scm_remember_upto_here_1 (argv); } SCM_GPROC (s_map, "map", 2, 0, 1, scm_map, g_map); /* Note: Currently, scm_map applies PROC to the argument list(s) sequentially, starting with the first element(s). This is used in evalext.c where the Scheme procedure `map-in-order', which guarantees sequential behaviour, is implemented using scm_map. If the behaviour changes, we need to update `map-in-order'. */ SCM scm_map (SCM proc, SCM arg1, SCM args) #define FUNC_NAME s_map { long i, len; SCM res = SCM_EOL; SCM *pres = &res; SCM *ve = &args; /* Keep args from being optimized away. */ len = scm_ilength (arg1); SCM_GASSERTn (len >= 0, g_map, scm_cons2 (proc, arg1, args), SCM_ARG2, s_map); SCM_VALIDATE_REST_ARGUMENT (args); if (SCM_NULLP (args)) { while (SCM_NIMP (arg1)) { *pres = scm_cons (scm_apply (proc, SCM_CAR (arg1), scm_listofnull), SCM_EOL); pres = SCM_CDRLOC (*pres); arg1 = SCM_CDR (arg1); } return res; } args = scm_vector (arg1 = scm_cons (arg1, args)); ve = SCM_VELTS (args); #ifndef SCM_RECKLESS check_map_args (args, len, g_map, proc, arg1, s_map); #endif while (1) { arg1 = SCM_EOL; for (i = SCM_VECTOR_LENGTH (args) - 1; i >= 0; i--) { if (SCM_IMP (ve[i])) return res; arg1 = scm_cons (SCM_CAR (ve[i]), arg1); ve[i] = SCM_CDR (ve[i]); } *pres = scm_cons (scm_apply (proc, arg1, SCM_EOL), SCM_EOL); pres = SCM_CDRLOC (*pres); } } #undef FUNC_NAME SCM_GPROC (s_for_each, "for-each", 2, 0, 1, scm_for_each, g_for_each); SCM scm_for_each (SCM proc, SCM arg1, SCM args) #define FUNC_NAME s_for_each { SCM *ve = &args; /* Keep args from being optimized away. */ long i, len; len = scm_ilength (arg1); SCM_GASSERTn (len >= 0, g_for_each, scm_cons2 (proc, arg1, args), SCM_ARG2, s_for_each); SCM_VALIDATE_REST_ARGUMENT (args); if SCM_NULLP (args) { while SCM_NIMP (arg1) { scm_apply (proc, SCM_CAR (arg1), scm_listofnull); arg1 = SCM_CDR (arg1); } return SCM_UNSPECIFIED; } args = scm_vector (arg1 = scm_cons (arg1, args)); ve = SCM_VELTS (args); #ifndef SCM_RECKLESS check_map_args (args, len, g_for_each, proc, arg1, s_for_each); #endif while (1) { arg1 = SCM_EOL; for (i = SCM_VECTOR_LENGTH (args) - 1; i >= 0; i--) { if SCM_IMP (ve[i]) return SCM_UNSPECIFIED; arg1 = scm_cons (SCM_CAR (ve[i]), arg1); ve[i] = SCM_CDR (ve[i]); } scm_apply (proc, arg1, SCM_EOL); } } #undef FUNC_NAME SCM scm_closure (SCM code, SCM env) { register SCM z; SCM_NEWCELL (z); SCM_SETCODE (z, code); SCM_SETENV (z, env); return z; } scm_t_bits scm_tc16_promise; SCM scm_makprom (SCM code) { SCM_RETURN_NEWSMOB (scm_tc16_promise, SCM_UNPACK (code)); } static int promise_print (SCM exp, SCM port, scm_print_state *pstate) { int writingp = SCM_WRITINGP (pstate); scm_puts ("#', port); return !0; } SCM_DEFINE (scm_force, "force", 1, 0, 0, (SCM x), "If the promise @var{x} has not been computed yet, compute and\n" "return @var{x}, otherwise just return the previously computed\n" "value.") #define FUNC_NAME s_scm_force { SCM_VALIDATE_SMOB (1, x, promise); if (!((1L << 16) & SCM_CELL_WORD_0 (x))) { SCM ans = scm_apply (SCM_CELL_OBJECT_1 (x), SCM_EOL, SCM_EOL); if (!((1L << 16) & SCM_CELL_WORD_0 (x))) { SCM_DEFER_INTS; SCM_SET_CELL_OBJECT_1 (x, ans); SCM_SET_CELL_WORD_0 (x, SCM_CELL_WORD_0 (x) | (1L << 16)); SCM_ALLOW_INTS; } } return SCM_CELL_OBJECT_1 (x); } #undef FUNC_NAME SCM_DEFINE (scm_promise_p, "promise?", 1, 0, 0, (SCM obj), "Return true if @var{obj} is a promise, i.e. a delayed computation\n" "(@pxref{Delayed evaluation,,,r5rs.info,The Revised^5 Report on Scheme}).") #define FUNC_NAME s_scm_promise_p { return SCM_BOOL (SCM_TYP16_PREDICATE (scm_tc16_promise, obj)); } #undef FUNC_NAME SCM_DEFINE (scm_cons_source, "cons-source", 3, 0, 0, (SCM xorig, SCM x, SCM y), "Create and return a new pair whose car and cdr are @var{x} and @var{y}.\n" "Any source properties associated with @var{xorig} are also associated\n" "with the new pair.") #define FUNC_NAME s_scm_cons_source { SCM p, z; SCM_NEWCELL (z); SCM_SET_CELL_OBJECT_0 (z, x); SCM_SET_CELL_OBJECT_1 (z, y); /* Copy source properties possibly associated with xorig. */ p = scm_whash_lookup (scm_source_whash, xorig); if (!SCM_IMP (p)) scm_whash_insert (scm_source_whash, z, p); return z; } #undef FUNC_NAME SCM_DEFINE (scm_copy_tree, "copy-tree", 1, 0, 0, (SCM obj), "Recursively copy the data tree that is bound to @var{obj}, and return a\n" "pointer to the new data structure. @code{copy-tree} recurses down the\n" "contents of both pairs and vectors (since both cons cells and vector\n" "cells may point to arbitrary objects), and stops recursing when it hits\n" "any other object.") #define FUNC_NAME s_scm_copy_tree { SCM ans, tl; if (SCM_IMP (obj)) return obj; if (SCM_VECTORP (obj)) { unsigned long i = SCM_VECTOR_LENGTH (obj); ans = scm_c_make_vector (i, SCM_UNSPECIFIED); while (i--) SCM_VELTS (ans)[i] = scm_copy_tree (SCM_VELTS (obj)[i]); return ans; } if (SCM_NCONSP (obj)) return obj; ans = tl = scm_cons_source (obj, scm_copy_tree (SCM_CAR (obj)), SCM_UNSPECIFIED); while (obj = SCM_CDR (obj), SCM_CONSP (obj)) { SCM_SETCDR (tl, scm_cons (scm_copy_tree (SCM_CAR (obj)), SCM_UNSPECIFIED)); tl = SCM_CDR (tl); } SCM_SETCDR (tl, obj); return ans; } #undef FUNC_NAME /* We have three levels of EVAL here: - scm_i_eval (exp, env) evaluates EXP in environment ENV. ENV is a lexical environment structure as used by the actual tree code evaluator. When ENV is a top-level environment, then changes to the current module are tracked by updating ENV so that it continues to be in sync with the current module. - scm_primitive_eval (exp) evaluates EXP in the top-level environment as determined by the current module. This is done by constructing a suitable environment and calling scm_i_eval. Thus, changes to the top-level module are tracked normally. - scm_eval (exp, mod) evaluates EXP while MOD is the current module. This is done by setting the current module to MOD, invoking scm_primitive_eval on EXP, and then restoring the current module to the value it had previously. That is, while EXP is evaluated, changes to the current module are tracked, but these changes do not persist when scm_eval returns. For each level of evals, there are two variants, distinguished by a _x suffix: the ordinary variant does not modify EXP while the _x variant can destructively modify EXP into something completely unintelligible. A Scheme data structure passed as EXP to one of the _x variants should not ever be used again for anything. So when in doubt, use the ordinary variant. */ SCM scm_i_eval_x (SCM exp, SCM env) { return SCM_XEVAL (exp, env); } SCM scm_i_eval (SCM exp, SCM env) { exp = scm_copy_tree (exp); return SCM_XEVAL (exp, env); } SCM scm_primitive_eval_x (SCM exp) { SCM env; SCM transformer = scm_current_module_transformer (); if (SCM_NIMP (transformer)) exp = scm_apply (transformer, exp, scm_listofnull); env = scm_top_level_env (scm_current_module_lookup_closure ()); return scm_i_eval_x (exp, env); } SCM_DEFINE (scm_primitive_eval, "primitive-eval", 1, 0, 0, (SCM exp), "Evaluate @var{exp} in the top-level environment specified by\n" "the current module.") #define FUNC_NAME s_scm_primitive_eval { SCM env; SCM transformer = scm_current_module_transformer (); if (SCM_NIMP (transformer)) exp = scm_apply (transformer, exp, scm_listofnull); env = scm_top_level_env (scm_current_module_lookup_closure ()); return scm_i_eval (exp, env); } #undef FUNC_NAME /* Eval does not take the second arg optionally. This is intentional * in order to be R5RS compatible, and to prepare for the new module * system, where we would like to make the choice of evaluation * environment explicit. */ static void change_environment (void *data) { SCM pair = SCM_PACK (data); SCM new_module = SCM_CAR (pair); SCM old_module = scm_current_module (); SCM_SETCDR (pair, old_module); scm_set_current_module (new_module); } static void restore_environment (void *data) { SCM pair = SCM_PACK (data); SCM old_module = SCM_CDR (pair); SCM new_module = scm_current_module (); SCM_SETCAR (pair, new_module); scm_set_current_module (old_module); } static SCM inner_eval_x (void *data) { return scm_primitive_eval_x (SCM_PACK(data)); } SCM scm_eval_x (SCM exp, SCM module) #define FUNC_NAME "eval!" { SCM_VALIDATE_MODULE (2, module); return scm_internal_dynamic_wind (change_environment, inner_eval_x, restore_environment, (void *) SCM_UNPACK (exp), (void *) SCM_UNPACK (scm_cons (module, SCM_BOOL_F))); } #undef FUNC_NAME static SCM inner_eval (void *data) { return scm_primitive_eval (SCM_PACK(data)); } SCM_DEFINE (scm_eval, "eval", 2, 0, 0, (SCM exp, SCM module), "Evaluate @var{exp}, a list representing a Scheme expression,\n" "in the top-level environment specified by @var{module}.\n" "While @var{exp} is evaluated (using @var{primitive-eval}),\n" "@var{module} is made the current module. The current module\n" "is reset to its previous value when @var{eval} returns.") #define FUNC_NAME s_scm_eval { SCM_VALIDATE_MODULE (2, module); return scm_internal_dynamic_wind (change_environment, inner_eval, restore_environment, (void *) SCM_UNPACK (exp), (void *) SCM_UNPACK (scm_cons (module, SCM_BOOL_F))); } #undef FUNC_NAME #if (SCM_DEBUG_DEPRECATED == 0) /* Use scm_current_module () or scm_interaction_environment () * instead. The former is the module selected during loading of code. * The latter is the module in which the user of this thread currently * types expressions. */ SCM scm_top_level_lookup_closure_var; SCM scm_system_transformer; /* Avoid using this functionality altogether (except for implementing * libguile, where you can use scm_i_eval or scm_i_eval_x). * * Applications should use either C level scm_eval_x or Scheme * scm_eval; or scm_primitive_eval_x or scm_primitive_eval. */ SCM scm_eval_3 (SCM obj, int copyp, SCM env) { if (copyp) return scm_i_eval (obj, env); else return scm_i_eval_x (obj, env); } SCM_DEFINE (scm_eval2, "eval2", 2, 0, 0, (SCM obj, SCM env_thunk), "Evaluate @var{exp}, a Scheme expression, in the environment\n" "designated by @var{lookup}, a symbol-lookup function." "Do not use this version of eval, it does not play well\n" "with the module system. Use @code{eval} or\n" "@code{primitive-eval} instead.") #define FUNC_NAME s_scm_eval2 { return scm_i_eval (obj, scm_top_level_env (env_thunk)); } #undef FUNC_NAME #endif /* DEPRECATED */ /* At this point, scm_deval and scm_dapply are generated. */ #ifdef DEBUG_EXTENSIONS # define DEVAL # include "eval.c" #endif void scm_init_eval () { scm_init_opts (scm_evaluator_traps, scm_evaluator_trap_table, SCM_N_EVALUATOR_TRAPS); scm_init_opts (scm_eval_options_interface, scm_eval_opts, SCM_N_EVAL_OPTIONS); scm_tc16_promise = scm_make_smob_type ("promise", 0); scm_set_smob_mark (scm_tc16_promise, scm_markcdr); scm_set_smob_print (scm_tc16_promise, promise_print); /* Dirk:Fixme:: make scm_undefineds local to eval.c: it's only used here. */ scm_undefineds = scm_cons (SCM_UNDEFINED, SCM_EOL); SCM_SETCDR (scm_undefineds, scm_undefineds); scm_listofnull = scm_cons (SCM_EOL, SCM_EOL); scm_f_apply = scm_c_define_subr ("apply", scm_tc7_lsubr_2, scm_apply); /* acros */ /* end of acros */ #if SCM_DEBUG_DEPRECATED == 0 scm_top_level_lookup_closure_var = scm_c_define ("*top-level-lookup-closure*", scm_make_fluid ()); scm_system_transformer = scm_c_define ("scm:eval-transformer", scm_make_fluid ()); #endif #ifndef SCM_MAGIC_SNARFER #include "libguile/eval.x" #endif scm_c_define ("nil", scm_lisp_nil); scm_c_define ("t", scm_t_lisp); scm_add_feature ("delay"); } #endif /* !DEVAL */ /* Local Variables: c-file-style: "gnu" End: */