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e20d7001 | 1 | /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002,2003,2004,2005,2006,2007,2008,2009 |
434f2f7a | 2 | * Free Software Foundation, Inc. |
0f2d19dd | 3 | * |
73be1d9e | 4 | * This library is free software; you can redistribute it and/or |
53befeb7 NJ |
5 | * modify it under the terms of the GNU Lesser General Public License |
6 | * as published by the Free Software Foundation; either version 3 of | |
7 | * the License, or (at your option) any later version. | |
0f2d19dd | 8 | * |
53befeb7 NJ |
9 | * This library is distributed in the hope that it will be useful, but |
10 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
73be1d9e MV |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | * Lesser General Public License for more details. | |
0f2d19dd | 13 | * |
73be1d9e MV |
14 | * You should have received a copy of the GNU Lesser General Public |
15 | * License along with this library; if not, write to the Free Software | |
53befeb7 NJ |
16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
17 | * 02110-1301 USA | |
73be1d9e | 18 | */ |
1bbd0b84 | 19 | |
0f2d19dd JB |
20 | \f |
21 | ||
6dbd0af5 | 22 | /* SECTION: This code is compiled once. |
0f2d19dd JB |
23 | */ |
24 | ||
dbb605f5 | 25 | #ifdef HAVE_CONFIG_H |
3d05f2e0 RB |
26 | # include <config.h> |
27 | #endif | |
0f2d19dd | 28 | |
f7439099 | 29 | #include <alloca.h> |
3d05f2e0 | 30 | |
f7439099 | 31 | #include "libguile/__scm.h" |
48b96f4b | 32 | |
e7313a9d | 33 | #include <assert.h> |
a0599745 | 34 | #include "libguile/_scm.h" |
21628685 DH |
35 | #include "libguile/alist.h" |
36 | #include "libguile/async.h" | |
37 | #include "libguile/continuations.h" | |
a0599745 | 38 | #include "libguile/debug.h" |
328dc9a3 | 39 | #include "libguile/deprecation.h" |
09074dbf | 40 | #include "libguile/dynwind.h" |
a0599745 | 41 | #include "libguile/eq.h" |
21628685 DH |
42 | #include "libguile/feature.h" |
43 | #include "libguile/fluids.h" | |
21628685 DH |
44 | #include "libguile/goops.h" |
45 | #include "libguile/hash.h" | |
46 | #include "libguile/hashtab.h" | |
47 | #include "libguile/lang.h" | |
4610b011 | 48 | #include "libguile/list.h" |
a0599745 | 49 | #include "libguile/macros.h" |
a0599745 MD |
50 | #include "libguile/modules.h" |
51 | #include "libguile/ports.h" | |
7e6e6b37 | 52 | #include "libguile/print.h" |
21628685 | 53 | #include "libguile/procprop.h" |
4abef68f | 54 | #include "libguile/programs.h" |
a0599745 | 55 | #include "libguile/root.h" |
21628685 DH |
56 | #include "libguile/smob.h" |
57 | #include "libguile/srcprop.h" | |
58 | #include "libguile/stackchk.h" | |
59 | #include "libguile/strings.h" | |
9de87eea | 60 | #include "libguile/threads.h" |
21628685 DH |
61 | #include "libguile/throw.h" |
62 | #include "libguile/validate.h" | |
a513ead3 | 63 | #include "libguile/values.h" |
21628685 | 64 | #include "libguile/vectors.h" |
4abef68f | 65 | #include "libguile/vm.h" |
a0599745 | 66 | |
a0599745 | 67 | #include "libguile/eval.h" |
0ee05b85 | 68 | #include "libguile/private-options.h" |
89efbff4 | 69 | |
0f2d19dd JB |
70 | \f |
71 | ||
0ee05b85 | 72 | |
212e58ed | 73 | static SCM unmemoize_exprs (SCM expr, SCM env); |
0f572ba7 | 74 | static SCM canonicalize_define (SCM expr); |
e5156567 | 75 | static SCM *scm_lookupcar1 (SCM vloc, SCM genv, int check); |
212e58ed | 76 | static SCM unmemoize_builtin_macro (SCM expr, SCM env); |
0ee05b85 HWN |
77 | static void ceval_letrec_inits (SCM env, SCM init_forms, SCM **init_values_eol); |
78 | static SCM ceval (SCM x, SCM env); | |
79 | static SCM deval (SCM x, SCM env); | |
0f572ba7 DH |
80 | |
81 | \f | |
82 | ||
e6729603 DH |
83 | /* {Syntax Errors} |
84 | * | |
85 | * This section defines the message strings for the syntax errors that can be | |
86 | * detected during memoization and the functions and macros that shall be | |
87 | * called by the memoizer code to signal syntax errors. */ | |
88 | ||
89 | ||
90 | /* Syntax errors that can be detected during memoization: */ | |
91 | ||
92 | /* Circular or improper lists do not form valid scheme expressions. If a | |
93 | * circular list or an improper list is detected in a place where a scheme | |
94 | * expression is expected, a 'Bad expression' error is signalled. */ | |
95 | static const char s_bad_expression[] = "Bad expression"; | |
96 | ||
89bff2fc DH |
97 | /* If a form is detected that holds a different number of expressions than are |
98 | * required in that context, a 'Missing or extra expression' error is | |
99 | * signalled. */ | |
100 | static const char s_expression[] = "Missing or extra expression in"; | |
101 | ||
cc56ba80 | 102 | /* If a form is detected that holds less expressions than are required in that |
8ae95199 | 103 | * context, a 'Missing expression' error is signalled. */ |
cc56ba80 DH |
104 | static const char s_missing_expression[] = "Missing expression in"; |
105 | ||
609a8b86 | 106 | /* If a form is detected that holds more expressions than are allowed in that |
8ae95199 | 107 | * context, an 'Extra expression' error is signalled. */ |
609a8b86 DH |
108 | static const char s_extra_expression[] = "Extra expression in"; |
109 | ||
89bff2fc DH |
110 | /* The empty combination '()' is not allowed as an expression in scheme. If |
111 | * it is detected in a place where an expression is expected, an 'Illegal | |
112 | * empty combination' error is signalled. Note: If you encounter this error | |
113 | * message, it is very likely that you intended to denote the empty list. To | |
114 | * do so, you need to quote the empty list like (quote ()) or '(). */ | |
115 | static const char s_empty_combination[] = "Illegal empty combination"; | |
116 | ||
c86c440b DH |
117 | /* A body may hold an arbitrary number of internal defines, followed by a |
118 | * non-empty sequence of expressions. If a body with an empty sequence of | |
119 | * expressions is detected, a 'Missing body expression' error is signalled. | |
120 | */ | |
121 | static const char s_missing_body_expression[] = "Missing body expression in"; | |
122 | ||
123 | /* A body may hold an arbitrary number of internal defines, followed by a | |
124 | * non-empty sequence of expressions. Each the definitions and the | |
125 | * expressions may be grouped arbitraryly with begin, but it is not allowed to | |
126 | * mix definitions and expressions. If a define form in a body mixes | |
127 | * definitions and expressions, a 'Mixed definitions and expressions' error is | |
6bff1368 | 128 | * signalled. */ |
c86c440b | 129 | static const char s_mixed_body_forms[] = "Mixed definitions and expressions in"; |
6bff1368 DH |
130 | /* Definitions are only allowed on the top level and at the start of a body. |
131 | * If a definition is detected anywhere else, a 'Bad define placement' error | |
132 | * is signalled. */ | |
133 | static const char s_bad_define[] = "Bad define placement"; | |
c86c440b | 134 | |
2a6f7afe DH |
135 | /* Case or cond expressions must have at least one clause. If a case or cond |
136 | * expression without any clauses is detected, a 'Missing clauses' error is | |
137 | * signalled. */ | |
138 | static const char s_missing_clauses[] = "Missing clauses"; | |
139 | ||
609a8b86 DH |
140 | /* If there is an 'else' clause in a case or a cond statement, it must be the |
141 | * last clause. If after the 'else' case clause further clauses are detected, | |
142 | * a 'Misplaced else clause' error is signalled. */ | |
143 | static const char s_misplaced_else_clause[] = "Misplaced else clause"; | |
144 | ||
2a6f7afe DH |
145 | /* If a case clause is detected that is not in the format |
146 | * (<label(s)> <expression1> <expression2> ...) | |
147 | * a 'Bad case clause' error is signalled. */ | |
148 | static const char s_bad_case_clause[] = "Bad case clause"; | |
149 | ||
2a6f7afe DH |
150 | /* If a case clause is detected where the <label(s)> element is neither a |
151 | * proper list nor (in case of the last clause) the syntactic keyword 'else', | |
152 | * a 'Bad case labels' error is signalled. Note: If you encounter this error | |
153 | * for an else-clause which seems to be syntactically correct, check if 'else' | |
154 | * is really a syntactic keyword in that context. If 'else' is bound in the | |
155 | * local or global environment, it is not considered a syntactic keyword, but | |
156 | * will be treated as any other variable. */ | |
157 | static const char s_bad_case_labels[] = "Bad case labels"; | |
158 | ||
159 | /* In a case statement all labels have to be distinct. If in a case statement | |
160 | * a label occurs more than once, a 'Duplicate case label' error is | |
161 | * signalled. */ | |
162 | static const char s_duplicate_case_label[] = "Duplicate case label"; | |
163 | ||
609a8b86 DH |
164 | /* If a cond clause is detected that is not in one of the formats |
165 | * (<test> <expression1> ...) or (else <expression1> <expression2> ...) | |
166 | * a 'Bad cond clause' error is signalled. */ | |
167 | static const char s_bad_cond_clause[] = "Bad cond clause"; | |
168 | ||
169 | /* If a cond clause is detected that uses the alternate '=>' form, but does | |
170 | * not hold a recipient element for the test result, a 'Missing recipient' | |
171 | * error is signalled. */ | |
172 | static const char s_missing_recipient[] = "Missing recipient in"; | |
173 | ||
cc56ba80 DH |
174 | /* If in a position where a variable name is required some other object is |
175 | * detected, a 'Bad variable' error is signalled. */ | |
176 | static const char s_bad_variable[] = "Bad variable"; | |
177 | ||
a954ce1d DH |
178 | /* Bindings for forms like 'let' and 'do' have to be given in a proper, |
179 | * possibly empty list. If any other object is detected in a place where a | |
180 | * list of bindings was required, a 'Bad bindings' error is signalled. */ | |
181 | static const char s_bad_bindings[] = "Bad bindings"; | |
182 | ||
183 | /* Depending on the syntactic context, a binding has to be in the format | |
184 | * (<variable> <expression>) or (<variable> <expression1> <expression2>). | |
185 | * If anything else is detected in a place where a binding was expected, a | |
186 | * 'Bad binding' error is signalled. */ | |
187 | static const char s_bad_binding[] = "Bad binding"; | |
188 | ||
4610b011 DH |
189 | /* Some syntactic forms don't allow variable names to appear more than once in |
190 | * a list of bindings. If such a situation is nevertheless detected, a | |
191 | * 'Duplicate binding' error is signalled. */ | |
192 | static const char s_duplicate_binding[] = "Duplicate binding"; | |
193 | ||
a954ce1d DH |
194 | /* If the exit form of a 'do' expression is not in the format |
195 | * (<test> <expression> ...) | |
196 | * a 'Bad exit clause' error is signalled. */ | |
197 | static const char s_bad_exit_clause[] = "Bad exit clause"; | |
198 | ||
03a3e941 DH |
199 | /* The formal function arguments of a lambda expression have to be either a |
200 | * single symbol or a non-cyclic list. For anything else a 'Bad formals' | |
201 | * error is signalled. */ | |
202 | static const char s_bad_formals[] = "Bad formals"; | |
203 | ||
204 | /* If in a lambda expression something else than a symbol is detected at a | |
205 | * place where a formal function argument is required, a 'Bad formal' error is | |
206 | * signalled. */ | |
207 | static const char s_bad_formal[] = "Bad formal"; | |
208 | ||
209 | /* If in the arguments list of a lambda expression an argument name occurs | |
210 | * more than once, a 'Duplicate formal' error is signalled. */ | |
211 | static const char s_duplicate_formal[] = "Duplicate formal"; | |
212 | ||
6f81708a DH |
213 | /* If the evaluation of an unquote-splicing expression gives something else |
214 | * than a proper list, a 'Non-list result for unquote-splicing' error is | |
215 | * signalled. */ | |
216 | static const char s_splicing[] = "Non-list result for unquote-splicing"; | |
217 | ||
9a848baf DH |
218 | /* If something else than an exact integer is detected as the argument for |
219 | * @slot-ref and @slot-set!, a 'Bad slot number' error is signalled. */ | |
220 | static const char s_bad_slot_number[] = "Bad slot number"; | |
221 | ||
e6729603 DH |
222 | |
223 | /* Signal a syntax error. We distinguish between the form that caused the | |
224 | * error and the enclosing expression. The error message will print out as | |
225 | * shown in the following pattern. The file name and line number are only | |
226 | * given when they can be determined from the erroneous form or from the | |
227 | * enclosing expression. | |
228 | * | |
229 | * <filename>: In procedure memoization: | |
230 | * <filename>: In file <name>, line <nr>: <error-message> in <expression>. */ | |
231 | ||
232 | SCM_SYMBOL (syntax_error_key, "syntax-error"); | |
233 | ||
234 | /* The prototype is needed to indicate that the function does not return. */ | |
235 | static void | |
236 | syntax_error (const char* const, const SCM, const SCM) SCM_NORETURN; | |
237 | ||
238 | static void | |
239 | syntax_error (const char* const msg, const SCM form, const SCM expr) | |
240 | { | |
cc95e00a | 241 | SCM msg_string = scm_from_locale_string (msg); |
e6729603 DH |
242 | SCM filename = SCM_BOOL_F; |
243 | SCM linenr = SCM_BOOL_F; | |
244 | const char *format; | |
245 | SCM args; | |
246 | ||
a61f4e0c | 247 | if (scm_is_pair (form)) |
e6729603 DH |
248 | { |
249 | filename = scm_source_property (form, scm_sym_filename); | |
250 | linenr = scm_source_property (form, scm_sym_line); | |
251 | } | |
252 | ||
a61f4e0c | 253 | if (scm_is_false (filename) && scm_is_false (linenr) && scm_is_pair (expr)) |
e6729603 DH |
254 | { |
255 | filename = scm_source_property (expr, scm_sym_filename); | |
256 | linenr = scm_source_property (expr, scm_sym_line); | |
257 | } | |
258 | ||
259 | if (!SCM_UNBNDP (expr)) | |
260 | { | |
7888309b | 261 | if (scm_is_true (filename)) |
e6729603 DH |
262 | { |
263 | format = "In file ~S, line ~S: ~A ~S in expression ~S."; | |
264 | args = scm_list_5 (filename, linenr, msg_string, form, expr); | |
265 | } | |
7888309b | 266 | else if (scm_is_true (linenr)) |
e6729603 DH |
267 | { |
268 | format = "In line ~S: ~A ~S in expression ~S."; | |
269 | args = scm_list_4 (linenr, msg_string, form, expr); | |
270 | } | |
271 | else | |
272 | { | |
273 | format = "~A ~S in expression ~S."; | |
274 | args = scm_list_3 (msg_string, form, expr); | |
275 | } | |
276 | } | |
277 | else | |
278 | { | |
7888309b | 279 | if (scm_is_true (filename)) |
e6729603 DH |
280 | { |
281 | format = "In file ~S, line ~S: ~A ~S."; | |
282 | args = scm_list_4 (filename, linenr, msg_string, form); | |
283 | } | |
7888309b | 284 | else if (scm_is_true (linenr)) |
e6729603 DH |
285 | { |
286 | format = "In line ~S: ~A ~S."; | |
287 | args = scm_list_3 (linenr, msg_string, form); | |
288 | } | |
289 | else | |
290 | { | |
291 | format = "~A ~S."; | |
292 | args = scm_list_2 (msg_string, form); | |
293 | } | |
294 | } | |
295 | ||
296 | scm_error (syntax_error_key, "memoization", format, args, SCM_BOOL_F); | |
297 | } | |
298 | ||
299 | ||
300 | /* Shortcut macros to simplify syntax error handling. */ | |
9cc37597 LC |
301 | #define ASSERT_SYNTAX(cond, message, form) \ |
302 | { if (SCM_UNLIKELY (!(cond))) \ | |
303 | syntax_error (message, form, SCM_UNDEFINED); } | |
304 | #define ASSERT_SYNTAX_2(cond, message, form, expr) \ | |
305 | { if (SCM_UNLIKELY (!(cond))) \ | |
306 | syntax_error (message, form, expr); } | |
e6729603 | 307 | |
249bab1c AW |
308 | static void error_unbound_variable (SCM symbol) SCM_NORETURN; |
309 | static void error_defined_variable (SCM symbol) SCM_NORETURN; | |
310 | ||
e6729603 DH |
311 | \f |
312 | ||
d0624e39 DH |
313 | /* {Ilocs} |
314 | * | |
315 | * Ilocs are memoized references to variables in local environment frames. | |
316 | * They are represented as three values: The relative offset of the | |
317 | * environment frame, the number of the binding within that frame, and a | |
318 | * boolean value indicating whether the binding is the last binding in the | |
319 | * frame. | |
a55c2b68 MV |
320 | * |
321 | * Frame numbers have 11 bits, relative offsets have 12 bits. | |
d0624e39 | 322 | */ |
7e6e6b37 | 323 | |
d0624e39 | 324 | #define SCM_ILOC00 SCM_MAKE_ITAG8(0L, scm_tc8_iloc) |
7e6e6b37 DH |
325 | #define SCM_IFRINC (0x00000100L) |
326 | #define SCM_ICDR (0x00080000L) | |
d0624e39 | 327 | #define SCM_IDINC (0x00100000L) |
7e6e6b37 DH |
328 | #define SCM_IFRAME(n) ((long)((SCM_ICDR-SCM_IFRINC)>>8) \ |
329 | & (SCM_UNPACK (n) >> 8)) | |
330 | #define SCM_IDIST(n) (SCM_UNPACK (n) >> 20) | |
331 | #define SCM_ICDRP(n) (SCM_ICDR & SCM_UNPACK (n)) | |
d0624e39 | 332 | #define SCM_IDSTMSK (-SCM_IDINC) |
a55c2b68 MV |
333 | #define SCM_IFRAMEMAX ((1<<11)-1) |
334 | #define SCM_IDISTMAX ((1<<12)-1) | |
d0624e39 DH |
335 | #define SCM_MAKE_ILOC(frame_nr, binding_nr, last_p) \ |
336 | SCM_PACK ( \ | |
337 | ((frame_nr) << 8) \ | |
338 | + ((binding_nr) << 20) \ | |
339 | + ((last_p) ? SCM_ICDR : 0) \ | |
340 | + scm_tc8_iloc ) | |
341 | ||
7e6e6b37 DH |
342 | void |
343 | scm_i_print_iloc (SCM iloc, SCM port) | |
344 | { | |
345 | scm_puts ("#@", port); | |
346 | scm_intprint ((long) SCM_IFRAME (iloc), 10, port); | |
347 | scm_putc (SCM_ICDRP (iloc) ? '-' : '+', port); | |
348 | scm_intprint ((long) SCM_IDIST (iloc), 10, port); | |
349 | } | |
350 | ||
d0624e39 DH |
351 | #if (SCM_DEBUG_DEBUGGING_SUPPORT == 1) |
352 | ||
353 | SCM scm_dbg_make_iloc (SCM frame, SCM binding, SCM cdrp); | |
90df793f | 354 | |
d0624e39 DH |
355 | SCM_DEFINE (scm_dbg_make_iloc, "dbg-make-iloc", 3, 0, 0, |
356 | (SCM frame, SCM binding, SCM cdrp), | |
357 | "Return a new iloc with frame offset @var{frame}, binding\n" | |
358 | "offset @var{binding} and the cdr flag @var{cdrp}.") | |
359 | #define FUNC_NAME s_scm_dbg_make_iloc | |
360 | { | |
c3c97a34 KR |
361 | return SCM_MAKE_ILOC ((scm_t_bits) scm_to_unsigned_integer (frame, 0, SCM_IFRAMEMAX), |
362 | (scm_t_bits) scm_to_unsigned_integer (binding, 0, SCM_IDISTMAX), | |
7888309b | 363 | scm_is_true (cdrp)); |
d0624e39 DH |
364 | } |
365 | #undef FUNC_NAME | |
366 | ||
367 | SCM scm_dbg_iloc_p (SCM obj); | |
90df793f | 368 | |
d0624e39 DH |
369 | SCM_DEFINE (scm_dbg_iloc_p, "dbg-iloc?", 1, 0, 0, |
370 | (SCM obj), | |
371 | "Return @code{#t} if @var{obj} is an iloc.") | |
372 | #define FUNC_NAME s_scm_dbg_iloc_p | |
373 | { | |
7888309b | 374 | return scm_from_bool (SCM_ILOCP (obj)); |
d0624e39 DH |
375 | } |
376 | #undef FUNC_NAME | |
377 | ||
378 | #endif | |
379 | ||
380 | \f | |
381 | ||
7e6e6b37 DH |
382 | /* {Evaluator byte codes (isyms)} |
383 | */ | |
384 | ||
385 | #define ISYMNUM(n) (SCM_ITAG8_DATA (n)) | |
386 | ||
387 | /* This table must agree with the list of SCM_IM_ constants in tags.h */ | |
388 | static const char *const isymnames[] = | |
389 | { | |
390 | "#@and", | |
391 | "#@begin", | |
392 | "#@case", | |
393 | "#@cond", | |
394 | "#@do", | |
395 | "#@if", | |
396 | "#@lambda", | |
397 | "#@let", | |
398 | "#@let*", | |
399 | "#@letrec", | |
400 | "#@or", | |
401 | "#@quote", | |
402 | "#@set!", | |
403 | "#@define", | |
404 | "#@apply", | |
405 | "#@call-with-current-continuation", | |
406 | "#@dispatch", | |
407 | "#@slot-ref", | |
408 | "#@slot-set!", | |
409 | "#@delay", | |
7e6e6b37 DH |
410 | "#@call-with-values", |
411 | "#@else", | |
412 | "#@arrow", | |
413 | "#@nil-cond", | |
414 | "#@bind" | |
415 | }; | |
416 | ||
417 | void | |
418 | scm_i_print_isym (SCM isym, SCM port) | |
419 | { | |
420 | const size_t isymnum = ISYMNUM (isym); | |
421 | if (isymnum < (sizeof isymnames / sizeof (char *))) | |
422 | scm_puts (isymnames[isymnum], port); | |
423 | else | |
424 | scm_ipruk ("isym", isym, port); | |
425 | } | |
426 | ||
427 | \f | |
428 | ||
e5156567 DH |
429 | /* The function lookup_symbol is used during memoization: Lookup the symbol in |
430 | * the environment. If there is no binding for the symbol, SCM_UNDEFINED is | |
57d23e25 DH |
431 | * returned. If the symbol is a global variable, the variable object to which |
432 | * the symbol is bound is returned. Finally, if the symbol is a local | |
433 | * variable the corresponding iloc object is returned. */ | |
6f81708a DH |
434 | |
435 | /* A helper function for lookup_symbol: Try to find the symbol in the top | |
436 | * level environment frame. The function returns SCM_UNDEFINED if the symbol | |
57d23e25 DH |
437 | * is unbound and it returns a variable object if the symbol is a global |
438 | * variable. */ | |
6f81708a DH |
439 | static SCM |
440 | lookup_global_symbol (const SCM symbol, const SCM top_level) | |
441 | { | |
442 | const SCM variable = scm_sym2var (symbol, top_level, SCM_BOOL_F); | |
7888309b | 443 | if (scm_is_false (variable)) |
57d23e25 | 444 | return SCM_UNDEFINED; |
6f81708a | 445 | else |
57d23e25 | 446 | return variable; |
6f81708a DH |
447 | } |
448 | ||
449 | static SCM | |
450 | lookup_symbol (const SCM symbol, const SCM env) | |
451 | { | |
452 | SCM frame_idx; | |
453 | unsigned int frame_nr; | |
454 | ||
455 | for (frame_idx = env, frame_nr = 0; | |
a61f4e0c | 456 | !scm_is_null (frame_idx); |
6f81708a DH |
457 | frame_idx = SCM_CDR (frame_idx), ++frame_nr) |
458 | { | |
459 | const SCM frame = SCM_CAR (frame_idx); | |
a61f4e0c | 460 | if (scm_is_pair (frame)) |
6f81708a DH |
461 | { |
462 | /* frame holds a local environment frame */ | |
463 | SCM symbol_idx; | |
464 | unsigned int symbol_nr; | |
465 | ||
466 | for (symbol_idx = SCM_CAR (frame), symbol_nr = 0; | |
a61f4e0c | 467 | scm_is_pair (symbol_idx); |
6f81708a DH |
468 | symbol_idx = SCM_CDR (symbol_idx), ++symbol_nr) |
469 | { | |
bc36d050 | 470 | if (scm_is_eq (SCM_CAR (symbol_idx), symbol)) |
6f81708a DH |
471 | /* found the symbol, therefore return the iloc */ |
472 | return SCM_MAKE_ILOC (frame_nr, symbol_nr, 0); | |
473 | } | |
bc36d050 | 474 | if (scm_is_eq (symbol_idx, symbol)) |
6f81708a DH |
475 | /* found the symbol as the last element of the current frame */ |
476 | return SCM_MAKE_ILOC (frame_nr, symbol_nr, 1); | |
477 | } | |
478 | else | |
479 | { | |
480 | /* no more local environment frames */ | |
481 | return lookup_global_symbol (symbol, frame); | |
482 | } | |
483 | } | |
484 | ||
485 | return lookup_global_symbol (symbol, SCM_BOOL_F); | |
486 | } | |
487 | ||
488 | ||
489 | /* Return true if the symbol is - from the point of view of a macro | |
490 | * transformer - a literal in the sense specified in chapter "pattern | |
491 | * language" of R5RS. In the code below, however, we don't match the | |
492 | * definition of R5RS exactly: It returns true if the identifier has no | |
493 | * binding or if it is a syntactic keyword. */ | |
494 | static int | |
495 | literal_p (const SCM symbol, const SCM env) | |
496 | { | |
57d23e25 DH |
497 | const SCM variable = lookup_symbol (symbol, env); |
498 | if (SCM_UNBNDP (variable)) | |
499 | return 1; | |
500 | if (SCM_VARIABLEP (variable) && SCM_MACROP (SCM_VARIABLE_REF (variable))) | |
6f81708a DH |
501 | return 1; |
502 | else | |
503 | return 0; | |
504 | } | |
17fa3fcf | 505 | |
5fb64383 DH |
506 | |
507 | /* Return true if the expression is self-quoting in the memoized code. Thus, | |
508 | * some other objects (like e. g. vectors) are reported as self-quoting, which | |
509 | * according to R5RS would need to be quoted. */ | |
510 | static int | |
511 | is_self_quoting_p (const SCM expr) | |
512 | { | |
a61f4e0c | 513 | if (scm_is_pair (expr)) |
5fb64383 | 514 | return 0; |
cc95e00a | 515 | else if (scm_is_symbol (expr)) |
5fb64383 | 516 | return 0; |
a61f4e0c | 517 | else if (scm_is_null (expr)) |
5fb64383 DH |
518 | return 0; |
519 | else return 1; | |
520 | } | |
521 | ||
0f2d19dd | 522 | |
212e58ed DH |
523 | SCM_SYMBOL (sym_three_question_marks, "???"); |
524 | ||
525 | static SCM | |
526 | unmemoize_expression (const SCM expr, const SCM env) | |
527 | { | |
528 | if (SCM_ILOCP (expr)) | |
529 | { | |
530 | SCM frame_idx; | |
531 | unsigned long int frame_nr; | |
532 | SCM symbol_idx; | |
533 | unsigned long int symbol_nr; | |
534 | ||
535 | for (frame_idx = env, frame_nr = SCM_IFRAME (expr); | |
536 | frame_nr != 0; | |
537 | frame_idx = SCM_CDR (frame_idx), --frame_nr) | |
538 | ; | |
539 | for (symbol_idx = SCM_CAAR (frame_idx), symbol_nr = SCM_IDIST (expr); | |
540 | symbol_nr != 0; | |
541 | symbol_idx = SCM_CDR (symbol_idx), --symbol_nr) | |
542 | ; | |
543 | return SCM_ICDRP (expr) ? symbol_idx : SCM_CAR (symbol_idx); | |
544 | } | |
545 | else if (SCM_VARIABLEP (expr)) | |
546 | { | |
547 | const SCM sym = scm_module_reverse_lookup (scm_env_module (env), expr); | |
7888309b | 548 | return scm_is_true (sym) ? sym : sym_three_question_marks; |
212e58ed | 549 | } |
4057a3e0 | 550 | else if (scm_is_simple_vector (expr)) |
212e58ed DH |
551 | { |
552 | return scm_list_2 (scm_sym_quote, expr); | |
553 | } | |
a61f4e0c | 554 | else if (!scm_is_pair (expr)) |
212e58ed DH |
555 | { |
556 | return expr; | |
557 | } | |
558 | else if (SCM_ISYMP (SCM_CAR (expr))) | |
559 | { | |
560 | return unmemoize_builtin_macro (expr, env); | |
561 | } | |
562 | else | |
563 | { | |
564 | return unmemoize_exprs (expr, env); | |
565 | } | |
566 | } | |
567 | ||
568 | ||
569 | static SCM | |
570 | unmemoize_exprs (const SCM exprs, const SCM env) | |
571 | { | |
90df793f | 572 | SCM r_result = SCM_EOL; |
9fcf3cbb | 573 | SCM expr_idx = exprs; |
90df793f DH |
574 | SCM um_expr; |
575 | ||
576 | /* Note that due to the current lazy memoizer we may find partially memoized | |
5fa0939c | 577 | * code during execution. In such code we have to expect improper lists of |
90df793f DH |
578 | * expressions: On the one hand, for such code syntax checks have not yet |
579 | * fully been performed, on the other hand, there may be even legal code | |
580 | * like '(a . b) appear as an improper list of expressions as long as the | |
581 | * quote expression is still in its unmemoized form. For this reason, the | |
582 | * following code handles improper lists of expressions until memoization | |
583 | * and execution have been completely separated. */ | |
a61f4e0c | 584 | for (; scm_is_pair (expr_idx); expr_idx = SCM_CDR (expr_idx)) |
212e58ed DH |
585 | { |
586 | const SCM expr = SCM_CAR (expr_idx); | |
5fa0939c DH |
587 | |
588 | /* In partially memoized code, lists of expressions that stem from a | |
589 | * body form may start with an ISYM if the body itself has not yet been | |
590 | * memoized. This isym is just an internal marker to indicate that the | |
591 | * body still needs to be memoized. An isym may occur at the very | |
592 | * beginning of the body or after one or more comment strings. It is | |
593 | * dropped during unmemoization. */ | |
594 | if (!SCM_ISYMP (expr)) | |
595 | { | |
596 | um_expr = unmemoize_expression (expr, env); | |
597 | r_result = scm_cons (um_expr, r_result); | |
598 | } | |
90df793f DH |
599 | } |
600 | um_expr = unmemoize_expression (expr_idx, env); | |
a61f4e0c | 601 | if (!scm_is_null (r_result)) |
90df793f DH |
602 | { |
603 | const SCM result = scm_reverse_x (r_result, SCM_UNDEFINED); | |
604 | SCM_SETCDR (r_result, um_expr); | |
605 | return result; | |
606 | } | |
607 | else | |
608 | { | |
609 | return um_expr; | |
212e58ed | 610 | } |
212e58ed DH |
611 | } |
612 | ||
613 | ||
34adf7ea DH |
614 | /* Rewrite the body (which is given as the list of expressions forming the |
615 | * body) into its internal form. The internal form of a body (<expr> ...) is | |
616 | * just the body itself, but prefixed with an ISYM that denotes to what kind | |
617 | * of outer construct this body belongs: (<ISYM> <expr> ...). A lambda body | |
618 | * starts with SCM_IM_LAMBDA, for example, a body of a let starts with | |
6bff1368 | 619 | * SCM_IM_LET, etc. |
34adf7ea DH |
620 | * |
621 | * It is assumed that the calling expression has already made sure that the | |
622 | * body is a proper list. */ | |
26d5b9b4 | 623 | static SCM |
430b8401 | 624 | m_body (SCM op, SCM exprs) |
26d5b9b4 | 625 | { |
26d5b9b4 | 626 | /* Don't add another ISYM if one is present already. */ |
34adf7ea DH |
627 | if (SCM_ISYMP (SCM_CAR (exprs))) |
628 | return exprs; | |
629 | else | |
630 | return scm_cons (op, exprs); | |
26d5b9b4 MD |
631 | } |
632 | ||
1cc91f1b | 633 | |
57d23e25 DH |
634 | /* The function m_expand_body memoizes a proper list of expressions forming a |
635 | * body. This function takes care of dealing with internal defines and | |
636 | * transforming them into an equivalent letrec expression. The list of | |
637 | * expressions is rewritten in place. */ | |
910b5125 | 638 | |
57d23e25 DH |
639 | /* This is a helper function for m_expand_body. If the argument expression is |
640 | * a symbol that denotes a syntactic keyword, the corresponding macro object | |
641 | * is returned, in all other cases the function returns SCM_UNDEFINED. */ | |
910b5125 DH |
642 | static SCM |
643 | try_macro_lookup (const SCM expr, const SCM env) | |
644 | { | |
cc95e00a | 645 | if (scm_is_symbol (expr)) |
910b5125 | 646 | { |
57d23e25 DH |
647 | const SCM variable = lookup_symbol (expr, env); |
648 | if (SCM_VARIABLEP (variable)) | |
649 | { | |
650 | const SCM value = SCM_VARIABLE_REF (variable); | |
651 | if (SCM_MACROP (value)) | |
652 | return value; | |
653 | } | |
910b5125 | 654 | } |
57d23e25 DH |
655 | |
656 | return SCM_UNDEFINED; | |
910b5125 DH |
657 | } |
658 | ||
659 | /* This is a helper function for m_expand_body. It expands user macros, | |
660 | * because for the correct translation of a body we need to know whether they | |
661 | * expand to a definition. */ | |
662 | static SCM | |
663 | expand_user_macros (SCM expr, const SCM env) | |
664 | { | |
a61f4e0c | 665 | while (scm_is_pair (expr)) |
910b5125 DH |
666 | { |
667 | const SCM car_expr = SCM_CAR (expr); | |
668 | const SCM new_car = expand_user_macros (car_expr, env); | |
669 | const SCM value = try_macro_lookup (new_car, env); | |
670 | ||
671 | if (SCM_MACROP (value) && SCM_MACRO_TYPE (value) == 2) | |
672 | { | |
673 | /* User macros transform code into code. */ | |
674 | expr = scm_call_2 (SCM_MACRO_CODE (value), expr, env); | |
675 | /* We need to reiterate on the transformed code. */ | |
676 | } | |
677 | else | |
678 | { | |
679 | /* No user macro: return. */ | |
680 | SCM_SETCAR (expr, new_car); | |
681 | return expr; | |
682 | } | |
683 | } | |
684 | ||
685 | return expr; | |
686 | } | |
687 | ||
688 | /* This is a helper function for m_expand_body. It determines if a given form | |
689 | * represents an application of a given built-in macro. The built-in macro to | |
690 | * check for is identified by its syntactic keyword. The form is an | |
691 | * application of the given macro if looking up the car of the form in the | |
692 | * given environment actually returns the built-in macro. */ | |
693 | static int | |
694 | is_system_macro_p (const SCM syntactic_keyword, const SCM form, const SCM env) | |
695 | { | |
a61f4e0c | 696 | if (scm_is_pair (form)) |
910b5125 DH |
697 | { |
698 | const SCM car_form = SCM_CAR (form); | |
699 | const SCM value = try_macro_lookup (car_form, env); | |
700 | if (SCM_BUILTIN_MACRO_P (value)) | |
701 | { | |
702 | const SCM macro_name = scm_macro_name (value); | |
bc36d050 | 703 | return scm_is_eq (macro_name, syntactic_keyword); |
910b5125 DH |
704 | } |
705 | } | |
706 | ||
707 | return 0; | |
708 | } | |
709 | ||
4d0949ea LC |
710 | static SCM |
711 | macroexp (SCM x, SCM env) | |
712 | { | |
713 | SCM res, proc, orig_sym; | |
714 | ||
715 | /* Don't bother to produce error messages here. We get them when we | |
716 | eventually execute the code for real. */ | |
717 | ||
718 | macro_tail: | |
719 | orig_sym = SCM_CAR (x); | |
720 | if (!scm_is_symbol (orig_sym)) | |
721 | return x; | |
722 | ||
723 | { | |
724 | SCM *proc_ptr = scm_lookupcar1 (x, env, 0); | |
725 | if (proc_ptr == NULL) | |
726 | { | |
727 | /* We have lost the race. */ | |
728 | goto macro_tail; | |
729 | } | |
730 | proc = *proc_ptr; | |
731 | } | |
732 | ||
733 | /* Only handle memoizing macros. `Acros' and `macros' are really | |
734 | special forms and should not be evaluated here. */ | |
735 | ||
736 | if (!SCM_MACROP (proc) | |
737 | || (SCM_MACRO_TYPE (proc) != 2 && !SCM_BUILTIN_MACRO_P (proc))) | |
738 | return x; | |
739 | ||
740 | SCM_SETCAR (x, orig_sym); /* Undo memoizing effect of lookupcar */ | |
741 | res = scm_call_2 (SCM_MACRO_CODE (proc), x, env); | |
742 | ||
743 | if (scm_ilength (res) <= 0) | |
744 | /* Result of expansion is not a list. */ | |
745 | return (scm_list_2 (SCM_IM_BEGIN, res)); | |
746 | else | |
747 | { | |
748 | /* njrev: Several queries here: (1) I don't see how it can be | |
749 | correct that the SCM_SETCAR 2 lines below this comment needs | |
750 | protection, but the SCM_SETCAR 6 lines above does not, so | |
751 | something here is probably wrong. (2) macroexp() is now only | |
752 | used in one place - scm_m_generalized_set_x - whereas all other | |
753 | macro expansion happens through expand_user_macros. Therefore | |
754 | (2.1) perhaps macroexp() could be eliminated completely now? | |
755 | (2.2) Does expand_user_macros need any critical section | |
756 | protection? */ | |
757 | ||
758 | SCM_CRITICAL_SECTION_START; | |
759 | SCM_SETCAR (x, SCM_CAR (res)); | |
760 | SCM_SETCDR (x, SCM_CDR (res)); | |
761 | SCM_CRITICAL_SECTION_END; | |
762 | ||
763 | goto macro_tail; | |
764 | } | |
765 | } | |
766 | ||
767 | \f | |
768 | /* Start of the memoizers for the standard R5RS builtin macros. */ | |
769 | ||
770 | static SCM scm_m_quote (SCM xorig, SCM env); | |
771 | static SCM scm_m_begin (SCM xorig, SCM env); | |
772 | static SCM scm_m_if (SCM xorig, SCM env); | |
773 | static SCM scm_m_set_x (SCM xorig, SCM env); | |
774 | static SCM scm_m_and (SCM xorig, SCM env); | |
775 | static SCM scm_m_or (SCM xorig, SCM env); | |
776 | static SCM scm_m_case (SCM xorig, SCM env); | |
777 | static SCM scm_m_cond (SCM xorig, SCM env); | |
778 | static SCM scm_m_lambda (SCM xorig, SCM env); | |
779 | static SCM scm_m_letstar (SCM xorig, SCM env); | |
780 | static SCM scm_m_do (SCM xorig, SCM env); | |
781 | static SCM scm_m_quasiquote (SCM xorig, SCM env); | |
782 | static SCM scm_m_delay (SCM xorig, SCM env); | |
783 | static SCM scm_m_generalized_set_x (SCM xorig, SCM env); | |
4d0949ea LC |
784 | static SCM scm_m_define (SCM x, SCM env); |
785 | static SCM scm_m_letrec (SCM xorig, SCM env); | |
786 | static SCM scm_m_let (SCM xorig, SCM env); | |
787 | static SCM scm_m_at (SCM xorig, SCM env); | |
788 | static SCM scm_m_atat (SCM xorig, SCM env); | |
789 | static SCM scm_m_atslot_ref (SCM xorig, SCM env); | |
790 | static SCM scm_m_atslot_set_x (SCM xorig, SCM env); | |
791 | static SCM scm_m_apply (SCM xorig, SCM env); | |
792 | static SCM scm_m_cont (SCM xorig, SCM env); | |
793 | #if SCM_ENABLE_ELISP | |
794 | static SCM scm_m_nil_cond (SCM xorig, SCM env); | |
795 | static SCM scm_m_atfop (SCM xorig, SCM env); | |
796 | #endif /* SCM_ENABLE_ELISP */ | |
797 | static SCM scm_m_atbind (SCM xorig, SCM env); | |
798 | static SCM scm_m_at_call_with_values (SCM xorig, SCM env); | |
799 | static SCM scm_m_eval_when (SCM xorig, SCM env); | |
800 | ||
801 | ||
9d4bf6d3 | 802 | static void |
910b5125 DH |
803 | m_expand_body (const SCM forms, const SCM env) |
804 | { | |
805 | /* The first body form can be skipped since it is known to be the ISYM that | |
806 | * was prepended to the body by m_body. */ | |
807 | SCM cdr_forms = SCM_CDR (forms); | |
808 | SCM form_idx = cdr_forms; | |
809 | SCM definitions = SCM_EOL; | |
810 | SCM sequence = SCM_EOL; | |
811 | ||
812 | /* According to R5RS, the list of body forms consists of two parts: a number | |
813 | * (maybe zero) of definitions, followed by a non-empty sequence of | |
814 | * expressions. Each the definitions and the expressions may be grouped | |
815 | * arbitrarily with begin, but it is not allowed to mix definitions and | |
816 | * expressions. The task of the following loop therefore is to split the | |
817 | * list of body forms into the list of definitions and the sequence of | |
818 | * expressions. */ | |
a61f4e0c | 819 | while (!scm_is_null (form_idx)) |
910b5125 DH |
820 | { |
821 | const SCM form = SCM_CAR (form_idx); | |
822 | const SCM new_form = expand_user_macros (form, env); | |
823 | if (is_system_macro_p (scm_sym_define, new_form, env)) | |
824 | { | |
825 | definitions = scm_cons (new_form, definitions); | |
826 | form_idx = SCM_CDR (form_idx); | |
827 | } | |
828 | else if (is_system_macro_p (scm_sym_begin, new_form, env)) | |
829 | { | |
830 | /* We have encountered a group of forms. This has to be either a | |
831 | * (possibly empty) group of (possibly further grouped) definitions, | |
832 | * or a non-empty group of (possibly further grouped) | |
833 | * expressions. */ | |
834 | const SCM grouped_forms = SCM_CDR (new_form); | |
835 | unsigned int found_definition = 0; | |
836 | unsigned int found_expression = 0; | |
837 | SCM grouped_form_idx = grouped_forms; | |
a61f4e0c | 838 | while (!found_expression && !scm_is_null (grouped_form_idx)) |
910b5125 DH |
839 | { |
840 | const SCM inner_form = SCM_CAR (grouped_form_idx); | |
841 | const SCM new_inner_form = expand_user_macros (inner_form, env); | |
842 | if (is_system_macro_p (scm_sym_define, new_inner_form, env)) | |
843 | { | |
844 | found_definition = 1; | |
845 | definitions = scm_cons (new_inner_form, definitions); | |
846 | grouped_form_idx = SCM_CDR (grouped_form_idx); | |
847 | } | |
848 | else if (is_system_macro_p (scm_sym_begin, new_inner_form, env)) | |
849 | { | |
850 | const SCM inner_group = SCM_CDR (new_inner_form); | |
851 | grouped_form_idx | |
852 | = scm_append (scm_list_2 (inner_group, | |
853 | SCM_CDR (grouped_form_idx))); | |
854 | } | |
855 | else | |
856 | { | |
857 | /* The group marks the start of the expressions of the body. | |
858 | * We have to make sure that within the same group we have | |
859 | * not encountered a definition before. */ | |
860 | ASSERT_SYNTAX (!found_definition, s_mixed_body_forms, form); | |
861 | found_expression = 1; | |
862 | grouped_form_idx = SCM_EOL; | |
863 | } | |
864 | } | |
865 | ||
866 | /* We have finished processing the group. If we have not yet | |
867 | * encountered an expression we continue processing the forms of the | |
868 | * body to collect further definition forms. Otherwise, the group | |
869 | * marks the start of the sequence of expressions of the body. */ | |
870 | if (!found_expression) | |
871 | { | |
872 | form_idx = SCM_CDR (form_idx); | |
873 | } | |
874 | else | |
875 | { | |
876 | sequence = form_idx; | |
877 | form_idx = SCM_EOL; | |
878 | } | |
879 | } | |
880 | else | |
881 | { | |
882 | /* We have detected a form which is no definition. This marks the | |
883 | * start of the sequence of expressions of the body. */ | |
884 | sequence = form_idx; | |
885 | form_idx = SCM_EOL; | |
886 | } | |
887 | } | |
888 | ||
889 | /* FIXME: forms does not hold information about the file location. */ | |
a61f4e0c | 890 | ASSERT_SYNTAX (scm_is_pair (sequence), s_missing_body_expression, cdr_forms); |
910b5125 | 891 | |
a61f4e0c | 892 | if (!scm_is_null (definitions)) |
910b5125 DH |
893 | { |
894 | SCM definition_idx; | |
895 | SCM letrec_tail; | |
896 | SCM letrec_expression; | |
897 | SCM new_letrec_expression; | |
910b5125 DH |
898 | |
899 | SCM bindings = SCM_EOL; | |
900 | for (definition_idx = definitions; | |
a61f4e0c | 901 | !scm_is_null (definition_idx); |
910b5125 DH |
902 | definition_idx = SCM_CDR (definition_idx)) |
903 | { | |
904 | const SCM definition = SCM_CAR (definition_idx); | |
905 | const SCM canonical_definition = canonicalize_define (definition); | |
906 | const SCM binding = SCM_CDR (canonical_definition); | |
907 | bindings = scm_cons (binding, bindings); | |
908 | }; | |
909 | ||
910 | letrec_tail = scm_cons (bindings, sequence); | |
911 | /* FIXME: forms does not hold information about the file location. */ | |
912 | letrec_expression = scm_cons_source (forms, scm_sym_letrec, letrec_tail); | |
913 | new_letrec_expression = scm_m_letrec (letrec_expression, env); | |
9d4bf6d3 MV |
914 | SCM_SETCAR (forms, new_letrec_expression); |
915 | SCM_SETCDR (forms, SCM_EOL); | |
910b5125 DH |
916 | } |
917 | else | |
918 | { | |
919 | SCM_SETCAR (forms, SCM_CAR (sequence)); | |
920 | SCM_SETCDR (forms, SCM_CDR (sequence)); | |
910b5125 DH |
921 | } |
922 | } | |
923 | ||
3b88ed2a | 924 | SCM_SYNTAX (s_and, "and", scm_i_makbimacro, scm_m_and); |
5f236208 | 925 | SCM_GLOBAL_SYMBOL (scm_sym_and, "and"); |
1cc91f1b | 926 | |
4d0949ea | 927 | static SCM |
e6729603 | 928 | scm_m_and (SCM expr, SCM env SCM_UNUSED) |
0f2d19dd | 929 | { |
e6729603 DH |
930 | const SCM cdr_expr = SCM_CDR (expr); |
931 | const long length = scm_ilength (cdr_expr); | |
932 | ||
933 | ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); | |
934 | ||
935 | if (length == 0) | |
936 | { | |
937 | /* Special case: (and) is replaced by #t. */ | |
938 | return SCM_BOOL_T; | |
939 | } | |
0f2d19dd | 940 | else |
e6729603 DH |
941 | { |
942 | SCM_SETCAR (expr, SCM_IM_AND); | |
943 | return expr; | |
944 | } | |
0f2d19dd JB |
945 | } |
946 | ||
212e58ed DH |
947 | static SCM |
948 | unmemoize_and (const SCM expr, const SCM env) | |
949 | { | |
950 | return scm_cons (scm_sym_and, unmemoize_exprs (SCM_CDR (expr), env)); | |
951 | } | |
952 | ||
1cc91f1b | 953 | |
3b88ed2a | 954 | SCM_SYNTAX (s_begin, "begin", scm_i_makbimacro, scm_m_begin); |
5f236208 | 955 | SCM_GLOBAL_SYMBOL (scm_sym_begin, "begin"); |
8ea46249 | 956 | |
4d0949ea | 957 | static SCM |
2a6f7afe | 958 | scm_m_begin (SCM expr, SCM env SCM_UNUSED) |
0f2d19dd | 959 | { |
2a6f7afe | 960 | const SCM cdr_expr = SCM_CDR (expr); |
21628685 DH |
961 | /* Dirk:FIXME:: An empty begin clause is not generally allowed by R5RS. |
962 | * That means, there should be a distinction between uses of begin where an | |
963 | * empty clause is OK and where it is not. */ | |
2a6f7afe DH |
964 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); |
965 | ||
966 | SCM_SETCAR (expr, SCM_IM_BEGIN); | |
967 | return expr; | |
0f2d19dd JB |
968 | } |
969 | ||
212e58ed DH |
970 | static SCM |
971 | unmemoize_begin (const SCM expr, const SCM env) | |
972 | { | |
973 | return scm_cons (scm_sym_begin, unmemoize_exprs (SCM_CDR (expr), env)); | |
974 | } | |
975 | ||
0f2d19dd | 976 | |
3b88ed2a | 977 | SCM_SYNTAX (s_case, "case", scm_i_makbimacro, scm_m_case); |
5f236208 | 978 | SCM_GLOBAL_SYMBOL (scm_sym_case, "case"); |
6f81708a | 979 | SCM_GLOBAL_SYMBOL (scm_sym_else, "else"); |
1cc91f1b | 980 | |
4d0949ea | 981 | static SCM |
2a6f7afe | 982 | scm_m_case (SCM expr, SCM env) |
0f2d19dd | 983 | { |
8ea46249 | 984 | SCM clauses; |
2a6f7afe DH |
985 | SCM all_labels = SCM_EOL; |
986 | ||
987 | /* Check, whether 'else is a literal, i. e. not bound to a value. */ | |
988 | const int else_literal_p = literal_p (scm_sym_else, env); | |
989 | ||
990 | const SCM cdr_expr = SCM_CDR (expr); | |
991 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
992 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_clauses, expr); | |
993 | ||
994 | clauses = SCM_CDR (cdr_expr); | |
a61f4e0c | 995 | while (!scm_is_null (clauses)) |
0f2d19dd | 996 | { |
2a6f7afe DH |
997 | SCM labels; |
998 | ||
999 | const SCM clause = SCM_CAR (clauses); | |
1000 | ASSERT_SYNTAX_2 (scm_ilength (clause) >= 2, | |
1001 | s_bad_case_clause, clause, expr); | |
1002 | ||
1003 | labels = SCM_CAR (clause); | |
a61f4e0c | 1004 | if (scm_is_pair (labels)) |
2a6f7afe DH |
1005 | { |
1006 | ASSERT_SYNTAX_2 (scm_ilength (labels) >= 0, | |
1007 | s_bad_case_labels, labels, expr); | |
26ecfa39 | 1008 | all_labels = scm_append (scm_list_2 (labels, all_labels)); |
2a6f7afe | 1009 | } |
a61f4e0c | 1010 | else if (scm_is_null (labels)) |
58a2510b DH |
1011 | { |
1012 | /* The list of labels is empty. According to R5RS this is allowed. | |
1013 | * It means that the sequence of expressions will never be executed. | |
1014 | * Therefore, as an optimization, we could remove the whole | |
1015 | * clause. */ | |
1016 | } | |
2a6f7afe DH |
1017 | else |
1018 | { | |
bc36d050 | 1019 | ASSERT_SYNTAX_2 (scm_is_eq (labels, scm_sym_else) && else_literal_p, |
2a6f7afe | 1020 | s_bad_case_labels, labels, expr); |
a61f4e0c | 1021 | ASSERT_SYNTAX_2 (scm_is_null (SCM_CDR (clauses)), |
609a8b86 | 1022 | s_misplaced_else_clause, clause, expr); |
2a6f7afe DH |
1023 | } |
1024 | ||
1025 | /* build the new clause */ | |
bc36d050 | 1026 | if (scm_is_eq (labels, scm_sym_else)) |
2a6f7afe DH |
1027 | SCM_SETCAR (clause, SCM_IM_ELSE); |
1028 | ||
8ea46249 | 1029 | clauses = SCM_CDR (clauses); |
0f2d19dd | 1030 | } |
2a6f7afe DH |
1031 | |
1032 | /* Check whether all case labels are distinct. */ | |
a61f4e0c | 1033 | for (; !scm_is_null (all_labels); all_labels = SCM_CDR (all_labels)) |
2a6f7afe DH |
1034 | { |
1035 | const SCM label = SCM_CAR (all_labels); | |
7888309b | 1036 | ASSERT_SYNTAX_2 (scm_is_false (scm_c_memq (label, SCM_CDR (all_labels))), |
4610b011 | 1037 | s_duplicate_case_label, label, expr); |
2a6f7afe DH |
1038 | } |
1039 | ||
1040 | SCM_SETCAR (expr, SCM_IM_CASE); | |
1041 | return expr; | |
0f2d19dd JB |
1042 | } |
1043 | ||
212e58ed DH |
1044 | static SCM |
1045 | unmemoize_case (const SCM expr, const SCM env) | |
1046 | { | |
1047 | const SCM um_key_expr = unmemoize_expression (SCM_CADR (expr), env); | |
1048 | SCM um_clauses = SCM_EOL; | |
1049 | SCM clause_idx; | |
1050 | ||
1051 | for (clause_idx = SCM_CDDR (expr); | |
a61f4e0c | 1052 | !scm_is_null (clause_idx); |
212e58ed DH |
1053 | clause_idx = SCM_CDR (clause_idx)) |
1054 | { | |
1055 | const SCM clause = SCM_CAR (clause_idx); | |
1056 | const SCM labels = SCM_CAR (clause); | |
1057 | const SCM exprs = SCM_CDR (clause); | |
1058 | ||
1059 | const SCM um_exprs = unmemoize_exprs (exprs, env); | |
bc36d050 | 1060 | const SCM um_labels = (scm_is_eq (labels, SCM_IM_ELSE)) |
212e58ed DH |
1061 | ? scm_sym_else |
1062 | : scm_i_finite_list_copy (labels); | |
1063 | const SCM um_clause = scm_cons (um_labels, um_exprs); | |
1064 | ||
1065 | um_clauses = scm_cons (um_clause, um_clauses); | |
1066 | } | |
1067 | um_clauses = scm_reverse_x (um_clauses, SCM_UNDEFINED); | |
1068 | ||
1069 | return scm_cons2 (scm_sym_case, um_key_expr, um_clauses); | |
1070 | } | |
1071 | ||
0f2d19dd | 1072 | |
3b88ed2a | 1073 | SCM_SYNTAX (s_cond, "cond", scm_i_makbimacro, scm_m_cond); |
5f236208 | 1074 | SCM_GLOBAL_SYMBOL (scm_sym_cond, "cond"); |
609a8b86 | 1075 | SCM_GLOBAL_SYMBOL (scm_sym_arrow, "=>"); |
1cc91f1b | 1076 | |
4d0949ea | 1077 | static SCM |
609a8b86 | 1078 | scm_m_cond (SCM expr, SCM env) |
0f2d19dd | 1079 | { |
609a8b86 DH |
1080 | /* Check, whether 'else or '=> is a literal, i. e. not bound to a value. */ |
1081 | const int else_literal_p = literal_p (scm_sym_else, env); | |
1082 | const int arrow_literal_p = literal_p (scm_sym_arrow, env); | |
1083 | ||
1084 | const SCM clauses = SCM_CDR (expr); | |
1085 | SCM clause_idx; | |
1086 | ||
1087 | ASSERT_SYNTAX (scm_ilength (clauses) >= 0, s_bad_expression, expr); | |
1088 | ASSERT_SYNTAX (scm_ilength (clauses) >= 1, s_missing_clauses, expr); | |
1089 | ||
1090 | for (clause_idx = clauses; | |
a61f4e0c | 1091 | !scm_is_null (clause_idx); |
609a8b86 | 1092 | clause_idx = SCM_CDR (clause_idx)) |
0f2d19dd | 1093 | { |
609a8b86 DH |
1094 | SCM test; |
1095 | ||
1096 | const SCM clause = SCM_CAR (clause_idx); | |
1097 | const long length = scm_ilength (clause); | |
1098 | ASSERT_SYNTAX_2 (length >= 1, s_bad_cond_clause, clause, expr); | |
1099 | ||
1100 | test = SCM_CAR (clause); | |
bc36d050 | 1101 | if (scm_is_eq (test, scm_sym_else) && else_literal_p) |
0f2d19dd | 1102 | { |
a61f4e0c | 1103 | const int last_clause_p = scm_is_null (SCM_CDR (clause_idx)); |
609a8b86 DH |
1104 | ASSERT_SYNTAX_2 (length >= 2, |
1105 | s_bad_cond_clause, clause, expr); | |
1106 | ASSERT_SYNTAX_2 (last_clause_p, | |
1107 | s_misplaced_else_clause, clause, expr); | |
1108 | SCM_SETCAR (clause, SCM_IM_ELSE); | |
0f2d19dd | 1109 | } |
609a8b86 | 1110 | else if (length >= 2 |
bc36d050 | 1111 | && scm_is_eq (SCM_CADR (clause), scm_sym_arrow) |
609a8b86 DH |
1112 | && arrow_literal_p) |
1113 | { | |
1114 | ASSERT_SYNTAX_2 (length > 2, s_missing_recipient, clause, expr); | |
1115 | ASSERT_SYNTAX_2 (length == 3, s_extra_expression, clause, expr); | |
1116 | SCM_SETCAR (SCM_CDR (clause), SCM_IM_ARROW); | |
8ea46249 | 1117 | } |
1fe1fc0a MV |
1118 | /* SRFI 61 extended cond */ |
1119 | else if (length >= 3 | |
1120 | && scm_is_eq (SCM_CADDR (clause), scm_sym_arrow) | |
1121 | && arrow_literal_p) | |
1122 | { | |
1123 | ASSERT_SYNTAX_2 (length > 3, s_missing_recipient, clause, expr); | |
1124 | ASSERT_SYNTAX_2 (length == 4, s_extra_expression, clause, expr); | |
1125 | SCM_SETCAR (SCM_CDDR (clause), SCM_IM_ARROW); | |
1126 | } | |
0f2d19dd | 1127 | } |
609a8b86 DH |
1128 | |
1129 | SCM_SETCAR (expr, SCM_IM_COND); | |
1130 | return expr; | |
0f2d19dd JB |
1131 | } |
1132 | ||
212e58ed DH |
1133 | static SCM |
1134 | unmemoize_cond (const SCM expr, const SCM env) | |
1135 | { | |
1136 | SCM um_clauses = SCM_EOL; | |
1137 | SCM clause_idx; | |
1138 | ||
1139 | for (clause_idx = SCM_CDR (expr); | |
a61f4e0c | 1140 | !scm_is_null (clause_idx); |
212e58ed DH |
1141 | clause_idx = SCM_CDR (clause_idx)) |
1142 | { | |
1143 | const SCM clause = SCM_CAR (clause_idx); | |
1144 | const SCM sequence = SCM_CDR (clause); | |
1145 | const SCM test = SCM_CAR (clause); | |
1146 | SCM um_test; | |
1147 | SCM um_sequence; | |
1148 | SCM um_clause; | |
1149 | ||
bc36d050 | 1150 | if (scm_is_eq (test, SCM_IM_ELSE)) |
212e58ed DH |
1151 | um_test = scm_sym_else; |
1152 | else | |
1153 | um_test = unmemoize_expression (test, env); | |
1154 | ||
a61f4e0c | 1155 | if (!scm_is_null (sequence) && scm_is_eq (SCM_CAR (sequence), |
bc36d050 | 1156 | SCM_IM_ARROW)) |
212e58ed DH |
1157 | { |
1158 | const SCM target = SCM_CADR (sequence); | |
1159 | const SCM um_target = unmemoize_expression (target, env); | |
1160 | um_sequence = scm_list_2 (scm_sym_arrow, um_target); | |
1161 | } | |
1162 | else | |
1163 | { | |
1164 | um_sequence = unmemoize_exprs (sequence, env); | |
1165 | } | |
1166 | ||
1167 | um_clause = scm_cons (um_test, um_sequence); | |
1168 | um_clauses = scm_cons (um_clause, um_clauses); | |
1169 | } | |
1170 | um_clauses = scm_reverse_x (um_clauses, SCM_UNDEFINED); | |
1171 | ||
1172 | return scm_cons (scm_sym_cond, um_clauses); | |
1173 | } | |
1174 | ||
1cc91f1b | 1175 | |
0f572ba7 | 1176 | SCM_SYNTAX (s_define, "define", scm_i_makbimacro, scm_m_define); |
5f236208 | 1177 | SCM_GLOBAL_SYMBOL (scm_sym_define, "define"); |
5280aaca | 1178 | |
9fbee57e DH |
1179 | /* Guile provides an extension to R5RS' define syntax to represent function |
1180 | * currying in a compact way. With this extension, it is allowed to write | |
1181 | * (define <nested-variable> <body>), where <nested-variable> has of one of | |
1182 | * the forms (<nested-variable> <formals>), (<nested-variable> . <formal>), | |
1183 | * (<variable> <formals>) or (<variable> . <formal>). As in R5RS, <formals> | |
1184 | * should be either a sequence of zero or more variables, or a sequence of one | |
1185 | * or more variables followed by a space-delimited period and another | |
1186 | * variable. Each level of argument nesting wraps the <body> within another | |
1187 | * lambda expression. For example, the following forms are allowed, each one | |
1188 | * followed by an equivalent, more explicit implementation. | |
1189 | * Example 1: | |
1190 | * (define ((a b . c) . d) <body>) is equivalent to | |
1191 | * (define a (lambda (b . c) (lambda d <body>))) | |
1192 | * Example 2: | |
1193 | * (define (((a) b) c . d) <body>) is equivalent to | |
1194 | * (define a (lambda () (lambda (b) (lambda (c . d) <body>)))) | |
1195 | */ | |
1196 | /* Dirk:FIXME:: We should provide an implementation for 'define' in the R5RS | |
1197 | * module that does not implement this extension. */ | |
0f572ba7 DH |
1198 | static SCM |
1199 | canonicalize_define (const SCM expr) | |
5280aaca | 1200 | { |
cc56ba80 DH |
1201 | SCM body; |
1202 | SCM variable; | |
1203 | ||
1204 | const SCM cdr_expr = SCM_CDR (expr); | |
c86c440b | 1205 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); |
cc56ba80 DH |
1206 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); |
1207 | ||
1208 | body = SCM_CDR (cdr_expr); | |
1209 | variable = SCM_CAR (cdr_expr); | |
a61f4e0c | 1210 | while (scm_is_pair (variable)) |
5280aaca | 1211 | { |
cc56ba80 DH |
1212 | /* This while loop realizes function currying by variable nesting. |
1213 | * Variable is known to be a nested-variable. In every iteration of the | |
1214 | * loop another level of lambda expression is created, starting with the | |
4610b011 DH |
1215 | * innermost one. Note that we don't check for duplicate formals here: |
1216 | * This will be done by the memoizer of the lambda expression. */ | |
cc56ba80 DH |
1217 | const SCM formals = SCM_CDR (variable); |
1218 | const SCM tail = scm_cons (formals, body); | |
1219 | ||
1220 | /* Add source properties to each new lambda expression: */ | |
1221 | const SCM lambda = scm_cons_source (variable, scm_sym_lambda, tail); | |
1222 | ||
1223 | body = scm_list_1 (lambda); | |
1224 | variable = SCM_CAR (variable); | |
5280aaca | 1225 | } |
cc95e00a | 1226 | ASSERT_SYNTAX_2 (scm_is_symbol (variable), s_bad_variable, variable, expr); |
cc56ba80 DH |
1227 | ASSERT_SYNTAX (scm_ilength (body) == 1, s_expression, expr); |
1228 | ||
0f572ba7 DH |
1229 | SCM_SETCAR (cdr_expr, variable); |
1230 | SCM_SETCDR (cdr_expr, body); | |
1231 | return expr; | |
1232 | } | |
1233 | ||
3dcf3373 LC |
1234 | /* According to Section 5.2.1 of R5RS we first have to make sure that the |
1235 | variable is bound, and then perform the `(set! variable expression)' | |
1236 | operation. However, EXPRESSION _can_ be evaluated before VARIABLE is | |
1237 | bound. This means that EXPRESSION won't necessarily be able to assign | |
1238 | values to VARIABLE as in `(define foo (begin (set! foo 1) (+ foo 1)))'. */ | |
4d0949ea | 1239 | static SCM |
0f572ba7 DH |
1240 | scm_m_define (SCM expr, SCM env) |
1241 | { | |
6bff1368 | 1242 | ASSERT_SYNTAX (SCM_TOP_LEVEL (env), s_bad_define, expr); |
0f572ba7 | 1243 | |
6bff1368 DH |
1244 | { |
1245 | const SCM canonical_definition = canonicalize_define (expr); | |
1246 | const SCM cdr_canonical_definition = SCM_CDR (canonical_definition); | |
1247 | const SCM variable = SCM_CAR (cdr_canonical_definition); | |
3dcf3373 | 1248 | const SCM value = scm_eval_car (SCM_CDR (cdr_canonical_definition), env); |
36245b66 DH |
1249 | const SCM location |
1250 | = scm_sym2var (variable, scm_env_top_level (env), SCM_BOOL_T); | |
6bff1368 | 1251 | |
6bff1368 DH |
1252 | if (SCM_REC_PROCNAMES_P) |
1253 | { | |
1254 | SCM tmp = value; | |
1255 | while (SCM_MACROP (tmp)) | |
1256 | tmp = SCM_MACRO_CODE (tmp); | |
23d72566 | 1257 | if (scm_is_true (scm_procedure_p (tmp)) |
6bff1368 | 1258 | /* Only the first definition determines the name. */ |
7888309b | 1259 | && scm_is_false (scm_procedure_property (tmp, scm_sym_name))) |
6bff1368 DH |
1260 | scm_set_procedure_property_x (tmp, scm_sym_name, variable); |
1261 | } | |
0f572ba7 | 1262 | |
36245b66 | 1263 | SCM_VARIABLE_SET (location, value); |
6bff1368 DH |
1264 | |
1265 | return SCM_UNSPECIFIED; | |
1266 | } | |
0f2d19dd JB |
1267 | } |
1268 | ||
1269 | ||
8ae95199 DH |
1270 | /* This is a helper function for forms (<keyword> <expression>) that are |
1271 | * transformed into (#@<keyword> '() <memoized_expression>) in order to allow | |
1272 | * for easy creation of a thunk (i. e. a closure without arguments) using the | |
1273 | * ('() <memoized_expression>) tail of the memoized form. */ | |
1274 | static SCM | |
1275 | memoize_as_thunk_prototype (const SCM expr, const SCM env SCM_UNUSED) | |
1276 | { | |
1277 | const SCM cdr_expr = SCM_CDR (expr); | |
1278 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1279 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 1, s_expression, expr); | |
1280 | ||
1281 | SCM_SETCDR (expr, scm_cons (SCM_EOL, cdr_expr)); | |
1282 | ||
1283 | return expr; | |
1284 | } | |
1285 | ||
1286 | ||
3b88ed2a | 1287 | SCM_SYNTAX (s_delay, "delay", scm_i_makbimacro, scm_m_delay); |
5f236208 | 1288 | SCM_GLOBAL_SYMBOL (scm_sym_delay, "delay"); |
1cc91f1b | 1289 | |
9fbee57e DH |
1290 | /* Promises are implemented as closures with an empty parameter list. Thus, |
1291 | * (delay <expression>) is transformed into (#@delay '() <expression>), where | |
1292 | * the empty list represents the empty parameter list. This representation | |
1293 | * allows for easy creation of the closure during evaluation. */ | |
4d0949ea | 1294 | static SCM |
8ae95199 | 1295 | scm_m_delay (SCM expr, SCM env) |
0f2d19dd | 1296 | { |
8ae95199 DH |
1297 | const SCM new_expr = memoize_as_thunk_prototype (expr, env); |
1298 | SCM_SETCAR (new_expr, SCM_IM_DELAY); | |
1299 | return new_expr; | |
0f2d19dd JB |
1300 | } |
1301 | ||
212e58ed DH |
1302 | static SCM |
1303 | unmemoize_delay (const SCM expr, const SCM env) | |
1304 | { | |
1305 | const SCM thunk_expr = SCM_CADDR (expr); | |
acbfb594 NJ |
1306 | /* A promise is implemented as a closure, and when applying a |
1307 | closure the evaluator adds a new frame to the environment - even | |
1308 | though, in the case of a promise, the added frame is always | |
1309 | empty. We need to extend the environment here in the same way, | |
1310 | so that any ILOCs in thunk_expr can be unmemoized correctly. */ | |
1311 | const SCM new_env = SCM_EXTEND_ENV (SCM_EOL, SCM_EOL, env); | |
1312 | return scm_list_2 (scm_sym_delay, unmemoize_expression (thunk_expr, new_env)); | |
212e58ed DH |
1313 | } |
1314 | ||
8ea46249 | 1315 | |
a954ce1d | 1316 | SCM_SYNTAX(s_do, "do", scm_i_makbimacro, scm_m_do); |
5f236208 | 1317 | SCM_GLOBAL_SYMBOL(scm_sym_do, "do"); |
a954ce1d | 1318 | |
302c12b4 | 1319 | /* DO gets the most radically altered syntax. The order of the vars is |
4610b011 DH |
1320 | * reversed here. During the evaluation this allows for simple consing of the |
1321 | * results of the inits and steps: | |
302c12b4 | 1322 | |
0f2d19dd | 1323 | (do ((<var1> <init1> <step1>) |
a954ce1d DH |
1324 | (<var2> <init2>) |
1325 | ... ) | |
1326 | (<test> <return>) | |
1327 | <body>) | |
302c12b4 | 1328 | |
0f2d19dd | 1329 | ;; becomes |
302c12b4 | 1330 | |
e681d187 | 1331 | (#@do (<init1> <init2> ... <initn>) |
a954ce1d DH |
1332 | (varn ... var2 var1) |
1333 | (<test> <return>) | |
1334 | (<body>) | |
1335 | <step1> <step2> ... <stepn>) ;; missing steps replaced by var | |
302c12b4 | 1336 | */ |
4d0949ea | 1337 | static SCM |
a954ce1d | 1338 | scm_m_do (SCM expr, SCM env SCM_UNUSED) |
0f2d19dd | 1339 | { |
a954ce1d DH |
1340 | SCM variables = SCM_EOL; |
1341 | SCM init_forms = SCM_EOL; | |
1342 | SCM step_forms = SCM_EOL; | |
1343 | SCM binding_idx; | |
1344 | SCM cddr_expr; | |
1345 | SCM exit_clause; | |
1346 | SCM commands; | |
1347 | SCM tail; | |
1348 | ||
1349 | const SCM cdr_expr = SCM_CDR (expr); | |
1350 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1351 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); | |
1352 | ||
1353 | /* Collect variables, init and step forms. */ | |
1354 | binding_idx = SCM_CAR (cdr_expr); | |
1355 | ASSERT_SYNTAX_2 (scm_ilength (binding_idx) >= 0, | |
1356 | s_bad_bindings, binding_idx, expr); | |
a61f4e0c | 1357 | for (; !scm_is_null (binding_idx); binding_idx = SCM_CDR (binding_idx)) |
0f2d19dd | 1358 | { |
a954ce1d DH |
1359 | const SCM binding = SCM_CAR (binding_idx); |
1360 | const long length = scm_ilength (binding); | |
1361 | ASSERT_SYNTAX_2 (length == 2 || length == 3, | |
1362 | s_bad_binding, binding, expr); | |
1363 | ||
302c12b4 | 1364 | { |
a954ce1d DH |
1365 | const SCM name = SCM_CAR (binding); |
1366 | const SCM init = SCM_CADR (binding); | |
1367 | const SCM step = (length == 2) ? name : SCM_CADDR (binding); | |
cc95e00a | 1368 | ASSERT_SYNTAX_2 (scm_is_symbol (name), s_bad_variable, name, expr); |
7888309b | 1369 | ASSERT_SYNTAX_2 (scm_is_false (scm_c_memq (name, variables)), |
4610b011 DH |
1370 | s_duplicate_binding, name, expr); |
1371 | ||
a954ce1d DH |
1372 | variables = scm_cons (name, variables); |
1373 | init_forms = scm_cons (init, init_forms); | |
1374 | step_forms = scm_cons (step, step_forms); | |
302c12b4 | 1375 | } |
0f2d19dd | 1376 | } |
a954ce1d DH |
1377 | init_forms = scm_reverse_x (init_forms, SCM_UNDEFINED); |
1378 | step_forms = scm_reverse_x (step_forms, SCM_UNDEFINED); | |
1379 | ||
1380 | /* Memoize the test form and the exit sequence. */ | |
1381 | cddr_expr = SCM_CDR (cdr_expr); | |
1382 | exit_clause = SCM_CAR (cddr_expr); | |
1383 | ASSERT_SYNTAX_2 (scm_ilength (exit_clause) >= 1, | |
1384 | s_bad_exit_clause, exit_clause, expr); | |
1385 | ||
1386 | commands = SCM_CDR (cddr_expr); | |
1387 | tail = scm_cons2 (exit_clause, commands, step_forms); | |
1388 | tail = scm_cons2 (init_forms, variables, tail); | |
1389 | SCM_SETCAR (expr, SCM_IM_DO); | |
1390 | SCM_SETCDR (expr, tail); | |
1391 | return expr; | |
0f2d19dd JB |
1392 | } |
1393 | ||
212e58ed DH |
1394 | static SCM |
1395 | unmemoize_do (const SCM expr, const SCM env) | |
1396 | { | |
1397 | const SCM cdr_expr = SCM_CDR (expr); | |
1398 | const SCM cddr_expr = SCM_CDR (cdr_expr); | |
1399 | const SCM rnames = SCM_CAR (cddr_expr); | |
1400 | const SCM extended_env = SCM_EXTEND_ENV (rnames, SCM_EOL, env); | |
1401 | const SCM cdddr_expr = SCM_CDR (cddr_expr); | |
1402 | const SCM exit_sequence = SCM_CAR (cdddr_expr); | |
1403 | const SCM um_exit_sequence = unmemoize_exprs (exit_sequence, extended_env); | |
1404 | const SCM cddddr_expr = SCM_CDR (cdddr_expr); | |
1405 | const SCM um_body = unmemoize_exprs (SCM_CAR (cddddr_expr), extended_env); | |
1406 | ||
1407 | /* build transformed binding list */ | |
1408 | SCM um_names = scm_reverse (rnames); | |
1409 | SCM um_inits = unmemoize_exprs (SCM_CAR (cdr_expr), env); | |
1410 | SCM um_steps = unmemoize_exprs (SCM_CDR (cddddr_expr), extended_env); | |
1411 | SCM um_bindings = SCM_EOL; | |
a61f4e0c | 1412 | while (!scm_is_null (um_names)) |
212e58ed DH |
1413 | { |
1414 | const SCM name = SCM_CAR (um_names); | |
1415 | const SCM init = SCM_CAR (um_inits); | |
1416 | SCM step = SCM_CAR (um_steps); | |
bc36d050 | 1417 | step = scm_is_eq (step, name) ? SCM_EOL : scm_list_1 (step); |
212e58ed DH |
1418 | |
1419 | um_bindings = scm_cons (scm_cons2 (name, init, step), um_bindings); | |
1420 | ||
1421 | um_names = SCM_CDR (um_names); | |
1422 | um_inits = SCM_CDR (um_inits); | |
1423 | um_steps = SCM_CDR (um_steps); | |
1424 | } | |
1425 | um_bindings = scm_reverse_x (um_bindings, SCM_UNDEFINED); | |
1426 | ||
1427 | return scm_cons (scm_sym_do, | |
1428 | scm_cons2 (um_bindings, um_exit_sequence, um_body)); | |
1429 | } | |
1430 | ||
b8229a3b | 1431 | |
3b88ed2a | 1432 | SCM_SYNTAX (s_if, "if", scm_i_makbimacro, scm_m_if); |
5f236208 | 1433 | SCM_GLOBAL_SYMBOL (scm_sym_if, "if"); |
b8229a3b | 1434 | |
4d0949ea | 1435 | static SCM |
4610b011 | 1436 | scm_m_if (SCM expr, SCM env SCM_UNUSED) |
0f2d19dd | 1437 | { |
4610b011 DH |
1438 | const SCM cdr_expr = SCM_CDR (expr); |
1439 | const long length = scm_ilength (cdr_expr); | |
1440 | ASSERT_SYNTAX (length == 2 || length == 3, s_expression, expr); | |
1441 | SCM_SETCAR (expr, SCM_IM_IF); | |
1442 | return expr; | |
0f2d19dd JB |
1443 | } |
1444 | ||
212e58ed DH |
1445 | static SCM |
1446 | unmemoize_if (const SCM expr, const SCM env) | |
1447 | { | |
1448 | const SCM cdr_expr = SCM_CDR (expr); | |
1449 | const SCM um_condition = unmemoize_expression (SCM_CAR (cdr_expr), env); | |
1450 | const SCM cddr_expr = SCM_CDR (cdr_expr); | |
1451 | const SCM um_then = unmemoize_expression (SCM_CAR (cddr_expr), env); | |
1452 | const SCM cdddr_expr = SCM_CDR (cddr_expr); | |
1453 | ||
a61f4e0c | 1454 | if (scm_is_null (cdddr_expr)) |
212e58ed DH |
1455 | { |
1456 | return scm_list_3 (scm_sym_if, um_condition, um_then); | |
1457 | } | |
1458 | else | |
1459 | { | |
1460 | const SCM um_else = unmemoize_expression (SCM_CAR (cdddr_expr), env); | |
1461 | return scm_list_4 (scm_sym_if, um_condition, um_then, um_else); | |
1462 | } | |
1463 | } | |
1464 | ||
302c12b4 | 1465 | |
3b88ed2a | 1466 | SCM_SYNTAX (s_lambda, "lambda", scm_i_makbimacro, scm_m_lambda); |
5f236208 | 1467 | SCM_GLOBAL_SYMBOL (scm_sym_lambda, "lambda"); |
0f2d19dd | 1468 | |
4610b011 DH |
1469 | /* A helper function for memoize_lambda to support checking for duplicate |
1470 | * formal arguments: Return true if OBJ is `eq?' to one of the elements of | |
1471 | * LIST or to the cdr of the last cons. Therefore, LIST may have any of the | |
1472 | * forms that a formal argument can have: | |
1473 | * <rest>, (<arg1> ...), (<arg1> ... . <rest>) */ | |
9fbee57e | 1474 | static int |
4610b011 | 1475 | c_improper_memq (SCM obj, SCM list) |
5cb22e96 | 1476 | { |
a61f4e0c | 1477 | for (; scm_is_pair (list); list = SCM_CDR (list)) |
9fbee57e | 1478 | { |
bc36d050 | 1479 | if (scm_is_eq (SCM_CAR (list), obj)) |
4610b011 | 1480 | return 1; |
9fbee57e | 1481 | } |
bc36d050 | 1482 | return scm_is_eq (list, obj); |
5cb22e96 DH |
1483 | } |
1484 | ||
4d0949ea | 1485 | static SCM |
03a3e941 | 1486 | scm_m_lambda (SCM expr, SCM env SCM_UNUSED) |
28d52ebb | 1487 | { |
9fbee57e | 1488 | SCM formals; |
03a3e941 | 1489 | SCM formals_idx; |
34adf7ea DH |
1490 | SCM cddr_expr; |
1491 | int documentation; | |
1492 | SCM body; | |
1493 | SCM new_body; | |
03a3e941 DH |
1494 | |
1495 | const SCM cdr_expr = SCM_CDR (expr); | |
1496 | const long length = scm_ilength (cdr_expr); | |
1497 | ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); | |
1498 | ASSERT_SYNTAX (length >= 2, s_missing_expression, expr); | |
28d52ebb | 1499 | |
03a3e941 DH |
1500 | /* Before iterating the list of formal arguments, make sure the formals |
1501 | * actually are given as either a symbol or a non-cyclic list. */ | |
1502 | formals = SCM_CAR (cdr_expr); | |
a61f4e0c | 1503 | if (scm_is_pair (formals)) |
03a3e941 DH |
1504 | { |
1505 | /* Dirk:FIXME:: We should check for a cyclic list of formals, and if | |
1506 | * detected, report a 'Bad formals' error. */ | |
1507 | } | |
1508 | else | |
1509 | { | |
a61f4e0c | 1510 | ASSERT_SYNTAX_2 (scm_is_symbol (formals) || scm_is_null (formals), |
03a3e941 DH |
1511 | s_bad_formals, formals, expr); |
1512 | } | |
1cc91f1b | 1513 | |
03a3e941 DH |
1514 | /* Now iterate the list of formal arguments to check if all formals are |
1515 | * symbols, and that there are no duplicates. */ | |
1516 | formals_idx = formals; | |
a61f4e0c | 1517 | while (scm_is_pair (formals_idx)) |
0f2d19dd | 1518 | { |
03a3e941 DH |
1519 | const SCM formal = SCM_CAR (formals_idx); |
1520 | const SCM next_idx = SCM_CDR (formals_idx); | |
cc95e00a | 1521 | ASSERT_SYNTAX_2 (scm_is_symbol (formal), s_bad_formal, formal, expr); |
03a3e941 DH |
1522 | ASSERT_SYNTAX_2 (!c_improper_memq (formal, next_idx), |
1523 | s_duplicate_formal, formal, expr); | |
1524 | formals_idx = next_idx; | |
0f2d19dd | 1525 | } |
a61f4e0c | 1526 | ASSERT_SYNTAX_2 (scm_is_null (formals_idx) || scm_is_symbol (formals_idx), |
03a3e941 | 1527 | s_bad_formal, formals_idx, expr); |
9fbee57e | 1528 | |
34adf7ea DH |
1529 | /* Memoize the body. Keep a potential documentation string. */ |
1530 | /* Dirk:FIXME:: We should probably extract the documentation string to | |
1531 | * some external database. Otherwise it will slow down execution, since | |
1532 | * the documentation string will have to be skipped with every execution | |
1533 | * of the closure. */ | |
1534 | cddr_expr = SCM_CDR (cdr_expr); | |
7f9994d9 | 1535 | documentation = (length >= 3 && scm_is_string (SCM_CAR (cddr_expr))); |
34adf7ea | 1536 | body = documentation ? SCM_CDR (cddr_expr) : cddr_expr; |
430b8401 | 1537 | new_body = m_body (SCM_IM_LAMBDA, body); |
34adf7ea DH |
1538 | |
1539 | SCM_SETCAR (expr, SCM_IM_LAMBDA); | |
1540 | if (documentation) | |
1541 | SCM_SETCDR (cddr_expr, new_body); | |
1542 | else | |
1543 | SCM_SETCDR (cdr_expr, new_body); | |
1544 | return expr; | |
0f2d19dd | 1545 | } |
6dbd0af5 | 1546 | |
212e58ed DH |
1547 | static SCM |
1548 | unmemoize_lambda (const SCM expr, const SCM env) | |
1549 | { | |
1550 | const SCM formals = SCM_CADR (expr); | |
1551 | const SCM body = SCM_CDDR (expr); | |
1552 | ||
1553 | const SCM new_env = SCM_EXTEND_ENV (formals, SCM_EOL, env); | |
1554 | const SCM um_formals = scm_i_finite_list_copy (formals); | |
1555 | const SCM um_body = unmemoize_exprs (body, new_env); | |
1556 | ||
1557 | return scm_cons2 (scm_sym_lambda, um_formals, um_body); | |
1558 | } | |
1559 | ||
0f2d19dd | 1560 | |
d6754c23 | 1561 | /* Check if the format of the bindings is ((<symbol> <init-form>) ...). */ |
302c12b4 | 1562 | static void |
d6754c23 | 1563 | check_bindings (const SCM bindings, const SCM expr) |
0f2d19dd | 1564 | { |
d6754c23 | 1565 | SCM binding_idx; |
302c12b4 | 1566 | |
d6754c23 DH |
1567 | ASSERT_SYNTAX_2 (scm_ilength (bindings) >= 0, |
1568 | s_bad_bindings, bindings, expr); | |
0f2d19dd | 1569 | |
d6754c23 | 1570 | binding_idx = bindings; |
a61f4e0c | 1571 | for (; !scm_is_null (binding_idx); binding_idx = SCM_CDR (binding_idx)) |
0f2d19dd | 1572 | { |
d6754c23 DH |
1573 | SCM name; /* const */ |
1574 | ||
1575 | const SCM binding = SCM_CAR (binding_idx); | |
1576 | ASSERT_SYNTAX_2 (scm_ilength (binding) == 2, | |
1577 | s_bad_binding, binding, expr); | |
1578 | ||
1579 | name = SCM_CAR (binding); | |
cc95e00a | 1580 | ASSERT_SYNTAX_2 (scm_is_symbol (name), s_bad_variable, name, expr); |
0f2d19dd | 1581 | } |
d6754c23 | 1582 | } |
26d5b9b4 | 1583 | |
d6754c23 DH |
1584 | |
1585 | /* The bindings, which must have the format ((v1 i1) (v2 i2) ... (vn in)), are | |
1586 | * transformed to the lists (vn ... v2 v1) and (i1 i2 ... in). That is, the | |
1587 | * variables are returned in a list with their order reversed, and the init | |
1588 | * forms are returned in a list in the same order as they are given in the | |
1589 | * bindings. If a duplicate variable name is detected, an error is | |
1590 | * signalled. */ | |
1591 | static void | |
1592 | transform_bindings ( | |
1593 | const SCM bindings, const SCM expr, | |
1594 | SCM *const rvarptr, SCM *const initptr ) | |
1595 | { | |
1596 | SCM rvariables = SCM_EOL; | |
1597 | SCM rinits = SCM_EOL; | |
1598 | SCM binding_idx = bindings; | |
a61f4e0c | 1599 | for (; !scm_is_null (binding_idx); binding_idx = SCM_CDR (binding_idx)) |
d6754c23 DH |
1600 | { |
1601 | const SCM binding = SCM_CAR (binding_idx); | |
1602 | const SCM cdr_binding = SCM_CDR (binding); | |
1603 | const SCM name = SCM_CAR (binding); | |
7888309b | 1604 | ASSERT_SYNTAX_2 (scm_is_false (scm_c_memq (name, rvariables)), |
d6754c23 DH |
1605 | s_duplicate_binding, name, expr); |
1606 | rvariables = scm_cons (name, rvariables); | |
1607 | rinits = scm_cons (SCM_CAR (cdr_binding), rinits); | |
1608 | } | |
1609 | *rvarptr = rvariables; | |
1610 | *initptr = scm_reverse_x (rinits, SCM_UNDEFINED); | |
0f2d19dd JB |
1611 | } |
1612 | ||
302c12b4 | 1613 | |
3b88ed2a | 1614 | SCM_SYNTAX(s_let, "let", scm_i_makbimacro, scm_m_let); |
5f236208 | 1615 | SCM_GLOBAL_SYMBOL(scm_sym_let, "let"); |
b8229a3b | 1616 | |
d6754c23 DH |
1617 | /* This function is a helper function for memoize_let. It transforms |
1618 | * (let name ((var init) ...) body ...) into | |
1619 | * ((letrec ((name (lambda (var ...) body ...))) name) init ...) | |
1620 | * and memoizes the expression. It is assumed that the caller has checked | |
1621 | * that name is a symbol and that there are bindings and a body. */ | |
1622 | static SCM | |
1623 | memoize_named_let (const SCM expr, const SCM env SCM_UNUSED) | |
1624 | { | |
1625 | SCM rvariables; | |
1626 | SCM variables; | |
1627 | SCM inits; | |
1628 | ||
1629 | const SCM cdr_expr = SCM_CDR (expr); | |
1630 | const SCM name = SCM_CAR (cdr_expr); | |
1631 | const SCM cddr_expr = SCM_CDR (cdr_expr); | |
1632 | const SCM bindings = SCM_CAR (cddr_expr); | |
1633 | check_bindings (bindings, expr); | |
1634 | ||
1635 | transform_bindings (bindings, expr, &rvariables, &inits); | |
1636 | variables = scm_reverse_x (rvariables, SCM_UNDEFINED); | |
1637 | ||
1638 | { | |
1639 | const SCM let_body = SCM_CDR (cddr_expr); | |
430b8401 | 1640 | const SCM lambda_body = m_body (SCM_IM_LET, let_body); |
d6754c23 DH |
1641 | const SCM lambda_tail = scm_cons (variables, lambda_body); |
1642 | const SCM lambda_form = scm_cons_source (expr, scm_sym_lambda, lambda_tail); | |
1643 | ||
1644 | const SCM rvar = scm_list_1 (name); | |
1645 | const SCM init = scm_list_1 (lambda_form); | |
430b8401 | 1646 | const SCM body = m_body (SCM_IM_LET, scm_list_1 (name)); |
d6754c23 DH |
1647 | const SCM letrec_tail = scm_cons (rvar, scm_cons (init, body)); |
1648 | const SCM letrec_form = scm_cons_source (expr, SCM_IM_LETREC, letrec_tail); | |
1649 | return scm_cons_source (expr, letrec_form, inits); | |
1650 | } | |
1651 | } | |
1652 | ||
1653 | /* (let ((v1 i1) (v2 i2) ...) body) with variables v1 .. vn and initializers | |
1654 | * i1 .. in is transformed to (#@let (vn ... v2 v1) (i1 i2 ...) body). */ | |
4d0949ea | 1655 | static SCM |
d6754c23 | 1656 | scm_m_let (SCM expr, SCM env) |
0f2d19dd | 1657 | { |
d6754c23 DH |
1658 | SCM bindings; |
1659 | ||
1660 | const SCM cdr_expr = SCM_CDR (expr); | |
1661 | const long length = scm_ilength (cdr_expr); | |
1662 | ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); | |
1663 | ASSERT_SYNTAX (length >= 2, s_missing_expression, expr); | |
302c12b4 | 1664 | |
d6754c23 | 1665 | bindings = SCM_CAR (cdr_expr); |
cc95e00a | 1666 | if (scm_is_symbol (bindings)) |
26d5b9b4 | 1667 | { |
d6754c23 DH |
1668 | ASSERT_SYNTAX (length >= 3, s_missing_expression, expr); |
1669 | return memoize_named_let (expr, env); | |
26d5b9b4 | 1670 | } |
d6754c23 DH |
1671 | |
1672 | check_bindings (bindings, expr); | |
a61f4e0c | 1673 | if (scm_is_null (bindings) || scm_is_null (SCM_CDR (bindings))) |
26d5b9b4 | 1674 | { |
d6754c23 | 1675 | /* Special case: no bindings or single binding => let* is faster. */ |
430b8401 | 1676 | const SCM body = m_body (SCM_IM_LET, SCM_CDR (cdr_expr)); |
d6754c23 | 1677 | return scm_m_letstar (scm_cons2 (SCM_CAR (expr), bindings, body), env); |
26d5b9b4 | 1678 | } |
302c12b4 DH |
1679 | else |
1680 | { | |
d6754c23 DH |
1681 | /* plain let */ |
1682 | SCM rvariables; | |
1683 | SCM inits; | |
1684 | transform_bindings (bindings, expr, &rvariables, &inits); | |
26d5b9b4 | 1685 | |
302c12b4 | 1686 | { |
430b8401 | 1687 | const SCM new_body = m_body (SCM_IM_LET, SCM_CDR (cdr_expr)); |
d6754c23 DH |
1688 | const SCM new_tail = scm_cons2 (rvariables, inits, new_body); |
1689 | SCM_SETCAR (expr, SCM_IM_LET); | |
1690 | SCM_SETCDR (expr, new_tail); | |
1691 | return expr; | |
302c12b4 DH |
1692 | } |
1693 | } | |
0f2d19dd JB |
1694 | } |
1695 | ||
212e58ed DH |
1696 | static SCM |
1697 | build_binding_list (SCM rnames, SCM rinits) | |
1698 | { | |
1699 | SCM bindings = SCM_EOL; | |
a61f4e0c | 1700 | while (!scm_is_null (rnames)) |
212e58ed DH |
1701 | { |
1702 | const SCM binding = scm_list_2 (SCM_CAR (rnames), SCM_CAR (rinits)); | |
1703 | bindings = scm_cons (binding, bindings); | |
1704 | rnames = SCM_CDR (rnames); | |
1705 | rinits = SCM_CDR (rinits); | |
1706 | } | |
1707 | return bindings; | |
1708 | } | |
1709 | ||
1710 | static SCM | |
1711 | unmemoize_let (const SCM expr, const SCM env) | |
1712 | { | |
1713 | const SCM cdr_expr = SCM_CDR (expr); | |
1714 | const SCM um_rnames = SCM_CAR (cdr_expr); | |
1715 | const SCM extended_env = SCM_EXTEND_ENV (um_rnames, SCM_EOL, env); | |
1716 | const SCM cddr_expr = SCM_CDR (cdr_expr); | |
1717 | const SCM um_inits = unmemoize_exprs (SCM_CAR (cddr_expr), env); | |
1718 | const SCM um_rinits = scm_reverse_x (um_inits, SCM_UNDEFINED); | |
1719 | const SCM um_bindings = build_binding_list (um_rnames, um_rinits); | |
1720 | const SCM um_body = unmemoize_exprs (SCM_CDR (cddr_expr), extended_env); | |
1721 | ||
1722 | return scm_cons2 (scm_sym_let, um_bindings, um_body); | |
1723 | } | |
1724 | ||
1725 | ||
1726 | SCM_SYNTAX(s_letrec, "letrec", scm_i_makbimacro, scm_m_letrec); | |
5f236208 | 1727 | SCM_GLOBAL_SYMBOL(scm_sym_letrec, "letrec"); |
212e58ed | 1728 | |
4d0949ea | 1729 | static SCM |
212e58ed DH |
1730 | scm_m_letrec (SCM expr, SCM env) |
1731 | { | |
1732 | SCM bindings; | |
1733 | ||
1734 | const SCM cdr_expr = SCM_CDR (expr); | |
1735 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1736 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); | |
1737 | ||
1738 | bindings = SCM_CAR (cdr_expr); | |
a61f4e0c | 1739 | if (scm_is_null (bindings)) |
212e58ed DH |
1740 | { |
1741 | /* no bindings, let* is executed faster */ | |
1742 | SCM body = m_body (SCM_IM_LETREC, SCM_CDR (cdr_expr)); | |
1743 | return scm_m_letstar (scm_cons2 (SCM_CAR (expr), SCM_EOL, body), env); | |
1744 | } | |
1745 | else | |
1746 | { | |
1747 | SCM rvariables; | |
1748 | SCM inits; | |
1749 | SCM new_body; | |
1750 | ||
1751 | check_bindings (bindings, expr); | |
1752 | transform_bindings (bindings, expr, &rvariables, &inits); | |
1753 | new_body = m_body (SCM_IM_LETREC, SCM_CDR (cdr_expr)); | |
1754 | return scm_cons2 (SCM_IM_LETREC, rvariables, scm_cons (inits, new_body)); | |
1755 | } | |
1756 | } | |
1757 | ||
1758 | static SCM | |
1759 | unmemoize_letrec (const SCM expr, const SCM env) | |
1760 | { | |
1761 | const SCM cdr_expr = SCM_CDR (expr); | |
1762 | const SCM um_rnames = SCM_CAR (cdr_expr); | |
1763 | const SCM extended_env = SCM_EXTEND_ENV (um_rnames, SCM_EOL, env); | |
1764 | const SCM cddr_expr = SCM_CDR (cdr_expr); | |
1765 | const SCM um_inits = unmemoize_exprs (SCM_CAR (cddr_expr), extended_env); | |
1766 | const SCM um_rinits = scm_reverse_x (um_inits, SCM_UNDEFINED); | |
1767 | const SCM um_bindings = build_binding_list (um_rnames, um_rinits); | |
1768 | const SCM um_body = unmemoize_exprs (SCM_CDR (cddr_expr), extended_env); | |
1769 | ||
1770 | return scm_cons2 (scm_sym_letrec, um_bindings, um_body); | |
1771 | } | |
1772 | ||
1773 | ||
0f2d19dd | 1774 | |
3b88ed2a | 1775 | SCM_SYNTAX (s_letstar, "let*", scm_i_makbimacro, scm_m_letstar); |
5f236208 | 1776 | SCM_GLOBAL_SYMBOL (scm_sym_letstar, "let*"); |
1cc91f1b | 1777 | |
d6754c23 DH |
1778 | /* (let* ((v1 i1) (v2 i2) ...) body) with variables v1 .. vn and initializers |
1779 | * i1 .. in is transformed into the form (#@let* (v1 i1 v2 i2 ...) body). */ | |
4d0949ea | 1780 | static SCM |
d6754c23 | 1781 | scm_m_letstar (SCM expr, SCM env SCM_UNUSED) |
0f2d19dd | 1782 | { |
d6754c23 | 1783 | SCM binding_idx; |
d6754c23 | 1784 | SCM new_body; |
0f2d19dd | 1785 | |
d6754c23 DH |
1786 | const SCM cdr_expr = SCM_CDR (expr); |
1787 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1788 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); | |
9fbee57e | 1789 | |
d6754c23 DH |
1790 | binding_idx = SCM_CAR (cdr_expr); |
1791 | check_bindings (binding_idx, expr); | |
1792 | ||
461bffb1 DH |
1793 | /* Transform ((v1 i1) (v2 i2) ...) into (v1 i1 v2 i2 ...). The |
1794 | * transformation is done in place. At the beginning of one iteration of | |
1795 | * the loop the variable binding_idx holds the form | |
1796 | * P1:( (vn . P2:(in . ())) . P3:( (vn+1 in+1) ... ) ), | |
1797 | * where P1, P2 and P3 indicate the pairs, that are relevant for the | |
1798 | * transformation. P1 and P2 are modified in the loop, P3 remains | |
1799 | * untouched. After the execution of the loop, P1 will hold | |
1800 | * P1:( vn . P2:(in . P3:( (vn+1 in+1) ... )) ) | |
1801 | * and binding_idx will hold P3. */ | |
a61f4e0c | 1802 | while (!scm_is_null (binding_idx)) |
9fbee57e | 1803 | { |
461bffb1 | 1804 | const SCM cdr_binding_idx = SCM_CDR (binding_idx); /* remember P3 */ |
d6754c23 DH |
1805 | const SCM binding = SCM_CAR (binding_idx); |
1806 | const SCM name = SCM_CAR (binding); | |
461bffb1 DH |
1807 | const SCM cdr_binding = SCM_CDR (binding); |
1808 | ||
1809 | SCM_SETCDR (cdr_binding, cdr_binding_idx); /* update P2 */ | |
1810 | SCM_SETCAR (binding_idx, name); /* update P1 */ | |
1811 | SCM_SETCDR (binding_idx, cdr_binding); /* update P1 */ | |
1812 | ||
1813 | binding_idx = cdr_binding_idx; /* continue with P3 */ | |
9fbee57e DH |
1814 | } |
1815 | ||
430b8401 | 1816 | new_body = m_body (SCM_IM_LETSTAR, SCM_CDR (cdr_expr)); |
461bffb1 DH |
1817 | SCM_SETCAR (expr, SCM_IM_LETSTAR); |
1818 | /* the bindings have been changed in place */ | |
1819 | SCM_SETCDR (cdr_expr, new_body); | |
1820 | return expr; | |
9fbee57e | 1821 | } |
b8229a3b | 1822 | |
212e58ed DH |
1823 | static SCM |
1824 | unmemoize_letstar (const SCM expr, const SCM env) | |
0f2d19dd | 1825 | { |
d6754c23 | 1826 | const SCM cdr_expr = SCM_CDR (expr); |
212e58ed DH |
1827 | const SCM body = SCM_CDR (cdr_expr); |
1828 | SCM bindings = SCM_CAR (cdr_expr); | |
1829 | SCM um_bindings = SCM_EOL; | |
1830 | SCM extended_env = env; | |
1831 | SCM um_body; | |
d6754c23 | 1832 | |
a61f4e0c | 1833 | while (!scm_is_null (bindings)) |
9fbee57e | 1834 | { |
212e58ed DH |
1835 | const SCM variable = SCM_CAR (bindings); |
1836 | const SCM init = SCM_CADR (bindings); | |
1837 | const SCM um_init = unmemoize_expression (init, extended_env); | |
1838 | um_bindings = scm_cons (scm_list_2 (variable, um_init), um_bindings); | |
1839 | extended_env = SCM_EXTEND_ENV (variable, SCM_BOOL_F, extended_env); | |
1840 | bindings = SCM_CDDR (bindings); | |
9fbee57e | 1841 | } |
212e58ed | 1842 | um_bindings = scm_reverse_x (um_bindings, SCM_UNDEFINED); |
d6754c23 | 1843 | |
212e58ed DH |
1844 | um_body = unmemoize_exprs (body, extended_env); |
1845 | ||
1846 | return scm_cons2 (scm_sym_letstar, um_bindings, um_body); | |
0f2d19dd JB |
1847 | } |
1848 | ||
73b64342 | 1849 | |
3b88ed2a | 1850 | SCM_SYNTAX (s_or, "or", scm_i_makbimacro, scm_m_or); |
5f236208 | 1851 | SCM_GLOBAL_SYMBOL (scm_sym_or, "or"); |
73b64342 | 1852 | |
4d0949ea | 1853 | static SCM |
21628685 | 1854 | scm_m_or (SCM expr, SCM env SCM_UNUSED) |
73b64342 | 1855 | { |
21628685 DH |
1856 | const SCM cdr_expr = SCM_CDR (expr); |
1857 | const long length = scm_ilength (cdr_expr); | |
1858 | ||
1859 | ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); | |
1860 | ||
1861 | if (length == 0) | |
1862 | { | |
1863 | /* Special case: (or) is replaced by #f. */ | |
1864 | return SCM_BOOL_F; | |
1865 | } | |
9fbee57e | 1866 | else |
21628685 DH |
1867 | { |
1868 | SCM_SETCAR (expr, SCM_IM_OR); | |
1869 | return expr; | |
1870 | } | |
73b64342 MD |
1871 | } |
1872 | ||
212e58ed DH |
1873 | static SCM |
1874 | unmemoize_or (const SCM expr, const SCM env) | |
1875 | { | |
1876 | return scm_cons (scm_sym_or, unmemoize_exprs (SCM_CDR (expr), env)); | |
1877 | } | |
1878 | ||
73b64342 | 1879 | |
9fbee57e | 1880 | SCM_SYNTAX (s_quasiquote, "quasiquote", scm_makacro, scm_m_quasiquote); |
5f236208 | 1881 | SCM_GLOBAL_SYMBOL (scm_sym_quasiquote, "quasiquote"); |
6f81708a DH |
1882 | SCM_GLOBAL_SYMBOL (scm_sym_unquote, "unquote"); |
1883 | SCM_GLOBAL_SYMBOL (scm_sym_uq_splicing, "unquote-splicing"); | |
9fbee57e DH |
1884 | |
1885 | /* Internal function to handle a quasiquotation: 'form' is the parameter in | |
1886 | * the call (quasiquotation form), 'env' is the environment where unquoted | |
1887 | * expressions will be evaluated, and 'depth' is the current quasiquotation | |
1888 | * nesting level and is known to be greater than zero. */ | |
1889 | static SCM | |
1890 | iqq (SCM form, SCM env, unsigned long int depth) | |
73b64342 | 1891 | { |
a61f4e0c | 1892 | if (scm_is_pair (form)) |
c96d76b8 | 1893 | { |
21628685 | 1894 | const SCM tmp = SCM_CAR (form); |
bc36d050 | 1895 | if (scm_is_eq (tmp, scm_sym_quasiquote)) |
9fbee57e | 1896 | { |
21628685 DH |
1897 | const SCM args = SCM_CDR (form); |
1898 | ASSERT_SYNTAX (scm_ilength (args) == 1, s_expression, form); | |
9fbee57e DH |
1899 | return scm_list_2 (tmp, iqq (SCM_CAR (args), env, depth + 1)); |
1900 | } | |
bc36d050 | 1901 | else if (scm_is_eq (tmp, scm_sym_unquote)) |
9fbee57e | 1902 | { |
21628685 DH |
1903 | const SCM args = SCM_CDR (form); |
1904 | ASSERT_SYNTAX (scm_ilength (args) == 1, s_expression, form); | |
9fbee57e DH |
1905 | if (depth - 1 == 0) |
1906 | return scm_eval_car (args, env); | |
1907 | else | |
1908 | return scm_list_2 (tmp, iqq (SCM_CAR (args), env, depth - 1)); | |
1909 | } | |
a61f4e0c | 1910 | else if (scm_is_pair (tmp) |
bc36d050 | 1911 | && scm_is_eq (SCM_CAR (tmp), scm_sym_uq_splicing)) |
9fbee57e | 1912 | { |
21628685 DH |
1913 | const SCM args = SCM_CDR (tmp); |
1914 | ASSERT_SYNTAX (scm_ilength (args) == 1, s_expression, form); | |
9fbee57e DH |
1915 | if (depth - 1 == 0) |
1916 | { | |
21628685 DH |
1917 | const SCM list = scm_eval_car (args, env); |
1918 | const SCM rest = SCM_CDR (form); | |
1919 | ASSERT_SYNTAX_2 (scm_ilength (list) >= 0, | |
1920 | s_splicing, list, form); | |
9fbee57e DH |
1921 | return scm_append (scm_list_2 (list, iqq (rest, env, depth))); |
1922 | } | |
1923 | else | |
1924 | return scm_cons (iqq (SCM_CAR (form), env, depth - 1), | |
1925 | iqq (SCM_CDR (form), env, depth)); | |
1926 | } | |
1927 | else | |
1928 | return scm_cons (iqq (SCM_CAR (form), env, depth), | |
1929 | iqq (SCM_CDR (form), env, depth)); | |
1930 | } | |
4057a3e0 MV |
1931 | else if (scm_is_vector (form)) |
1932 | return scm_vector (iqq (scm_vector_to_list (form), env, depth)); | |
9fbee57e DH |
1933 | else |
1934 | return form; | |
1935 | } | |
1936 | ||
4d0949ea | 1937 | static SCM |
21628685 | 1938 | scm_m_quasiquote (SCM expr, SCM env) |
9fbee57e | 1939 | { |
21628685 DH |
1940 | const SCM cdr_expr = SCM_CDR (expr); |
1941 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1942 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 1, s_expression, expr); | |
1943 | return iqq (SCM_CAR (cdr_expr), env, 1); | |
9fbee57e DH |
1944 | } |
1945 | ||
1946 | ||
3b88ed2a | 1947 | SCM_SYNTAX (s_quote, "quote", scm_i_makbimacro, scm_m_quote); |
5f236208 | 1948 | SCM_GLOBAL_SYMBOL (scm_sym_quote, "quote"); |
9fbee57e | 1949 | |
4d0949ea | 1950 | static SCM |
21628685 | 1951 | scm_m_quote (SCM expr, SCM env SCM_UNUSED) |
9fbee57e | 1952 | { |
21628685 DH |
1953 | SCM quotee; |
1954 | ||
1955 | const SCM cdr_expr = SCM_CDR (expr); | |
1956 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1957 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 1, s_expression, expr); | |
1958 | quotee = SCM_CAR (cdr_expr); | |
5fb64383 | 1959 | if (is_self_quoting_p (quotee)) |
21628685 | 1960 | return quotee; |
e7313a9d | 1961 | |
21628685 | 1962 | SCM_SETCAR (expr, SCM_IM_QUOTE); |
e7313a9d | 1963 | SCM_SETCDR (expr, quotee); |
21628685 | 1964 | return expr; |
9fbee57e DH |
1965 | } |
1966 | ||
e7313a9d DH |
1967 | static SCM |
1968 | unmemoize_quote (const SCM expr, const SCM env SCM_UNUSED) | |
1969 | { | |
1970 | return scm_list_2 (scm_sym_quote, SCM_CDR (expr)); | |
1971 | } | |
1972 | ||
9fbee57e DH |
1973 | |
1974 | /* Will go into the RnRS module when Guile is factorized. | |
3b88ed2a | 1975 | SCM_SYNTAX (s_set_x, "set!", scm_i_makbimacro, scm_m_set_x); */ |
5f236208 | 1976 | SCM_GLOBAL_SYMBOL (scm_sym_set_x, "set!"); |
9fbee57e | 1977 | |
4d0949ea | 1978 | static SCM |
82b3e2c6 | 1979 | scm_m_set_x (SCM expr, SCM env SCM_UNUSED) |
9fbee57e | 1980 | { |
82b3e2c6 | 1981 | SCM variable; |
36245b66 | 1982 | SCM new_variable; |
82b3e2c6 DH |
1983 | |
1984 | const SCM cdr_expr = SCM_CDR (expr); | |
1985 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1986 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 2, s_expression, expr); | |
1987 | variable = SCM_CAR (cdr_expr); | |
36245b66 DH |
1988 | |
1989 | /* Memoize the variable form. */ | |
cc95e00a | 1990 | ASSERT_SYNTAX_2 (scm_is_symbol (variable), s_bad_variable, variable, expr); |
36245b66 | 1991 | new_variable = lookup_symbol (variable, env); |
36245b66 DH |
1992 | /* Leave the memoization of unbound symbols to lazy memoization: */ |
1993 | if (SCM_UNBNDP (new_variable)) | |
1994 | new_variable = variable; | |
82b3e2c6 DH |
1995 | |
1996 | SCM_SETCAR (expr, SCM_IM_SET_X); | |
36245b66 | 1997 | SCM_SETCAR (cdr_expr, new_variable); |
82b3e2c6 | 1998 | return expr; |
9fbee57e DH |
1999 | } |
2000 | ||
212e58ed DH |
2001 | static SCM |
2002 | unmemoize_set_x (const SCM expr, const SCM env) | |
2003 | { | |
2004 | return scm_cons (scm_sym_set_x, unmemoize_exprs (SCM_CDR (expr), env)); | |
2005 | } | |
2006 | ||
9fbee57e | 2007 | |
4d0949ea | 2008 | \f |
9fbee57e DH |
2009 | /* Start of the memoizers for non-R5RS builtin macros. */ |
2010 | ||
2011 | ||
249bab1c | 2012 | SCM_SYNTAX (s_at, "@", scm_makmmacro, scm_m_at); |
5f236208 | 2013 | SCM_GLOBAL_SYMBOL (scm_sym_at, "@"); |
249bab1c | 2014 | |
4d0949ea | 2015 | static SCM |
249bab1c AW |
2016 | scm_m_at (SCM expr, SCM env SCM_UNUSED) |
2017 | { | |
2018 | SCM mod, var; | |
2019 | ASSERT_SYNTAX (scm_ilength (expr) == 3, s_bad_expression, expr); | |
2020 | ASSERT_SYNTAX (scm_ilength (scm_cadr (expr)) > 0, s_bad_expression, expr); | |
69dd78d7 | 2021 | ASSERT_SYNTAX (scm_is_symbol (scm_caddr (expr)), s_bad_expression, expr); |
249bab1c AW |
2022 | |
2023 | mod = scm_resolve_module (scm_cadr (expr)); | |
2024 | if (scm_is_false (mod)) | |
2025 | error_unbound_variable (expr); | |
2026 | var = scm_module_variable (scm_module_public_interface (mod), scm_caddr (expr)); | |
2027 | if (scm_is_false (var)) | |
2028 | error_unbound_variable (expr); | |
2029 | ||
2030 | return var; | |
2031 | } | |
2032 | ||
2033 | SCM_SYNTAX (s_atat, "@@", scm_makmmacro, scm_m_atat); | |
5f236208 | 2034 | SCM_GLOBAL_SYMBOL (scm_sym_atat, "@@"); |
249bab1c | 2035 | |
4d0949ea | 2036 | static SCM |
249bab1c AW |
2037 | scm_m_atat (SCM expr, SCM env SCM_UNUSED) |
2038 | { | |
2039 | SCM mod, var; | |
2040 | ASSERT_SYNTAX (scm_ilength (expr) == 3, s_bad_expression, expr); | |
2041 | ASSERT_SYNTAX (scm_ilength (scm_cadr (expr)) > 0, s_bad_expression, expr); | |
69dd78d7 | 2042 | ASSERT_SYNTAX (scm_is_symbol (scm_caddr (expr)), s_bad_expression, expr); |
249bab1c AW |
2043 | |
2044 | mod = scm_resolve_module (scm_cadr (expr)); | |
2045 | if (scm_is_false (mod)) | |
2046 | error_unbound_variable (expr); | |
2047 | var = scm_module_variable (mod, scm_caddr (expr)); | |
2048 | if (scm_is_false (var)) | |
2049 | error_unbound_variable (expr); | |
2050 | ||
2051 | return var; | |
2052 | } | |
2053 | ||
3b88ed2a | 2054 | SCM_SYNTAX (s_atapply, "@apply", scm_i_makbimacro, scm_m_apply); |
5f236208 LC |
2055 | SCM_GLOBAL_SYMBOL (scm_sym_atapply, "@apply"); |
2056 | SCM_GLOBAL_SYMBOL (scm_sym_apply, "apply"); | |
9fbee57e | 2057 | |
4d0949ea | 2058 | static SCM |
82b3e2c6 | 2059 | scm_m_apply (SCM expr, SCM env SCM_UNUSED) |
9fbee57e | 2060 | { |
82b3e2c6 DH |
2061 | const SCM cdr_expr = SCM_CDR (expr); |
2062 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
2063 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 2, s_missing_expression, expr); | |
2e171178 | 2064 | |
82b3e2c6 DH |
2065 | SCM_SETCAR (expr, SCM_IM_APPLY); |
2066 | return expr; | |
2067 | } | |
2e171178 | 2068 | |
212e58ed DH |
2069 | static SCM |
2070 | unmemoize_apply (const SCM expr, const SCM env) | |
2071 | { | |
2072 | return scm_list_2 (scm_sym_atapply, unmemoize_exprs (SCM_CDR (expr), env)); | |
2073 | } | |
2074 | ||
2e171178 | 2075 | |
3b88ed2a | 2076 | SCM_SYNTAX (s_atbind, "@bind", scm_i_makbimacro, scm_m_atbind); |
73b64342 | 2077 | |
82b3e2c6 DH |
2078 | /* FIXME: The following explanation should go into the documentation: */ |
2079 | /* (@bind ((var init) ...) body ...) will assign the values of the `init's to | |
2080 | * the global variables named by `var's (symbols, not evaluated), creating | |
2081 | * them if they don't exist, executes body, and then restores the previous | |
2082 | * values of the `var's. Additionally, whenever control leaves body, the | |
2083 | * values of the `var's are saved and restored when control returns. It is an | |
2084 | * error when a symbol appears more than once among the `var's. All `init's | |
2085 | * are evaluated before any `var' is set. | |
2086 | * | |
2087 | * Think of this as `let' for dynamic scope. | |
2088 | */ | |
2089 | ||
2090 | /* (@bind ((var1 exp1) ... (varn expn)) body ...) is memoized into | |
2091 | * (#@bind ((varn ... var1) . (exp1 ... expn)) body ...). | |
2092 | * | |
2093 | * FIXME - also implement `@bind*'. | |
2094 | */ | |
4d0949ea | 2095 | static SCM |
82b3e2c6 | 2096 | scm_m_atbind (SCM expr, SCM env) |
73b64342 | 2097 | { |
82b3e2c6 DH |
2098 | SCM bindings; |
2099 | SCM rvariables; | |
2100 | SCM inits; | |
2101 | SCM variable_idx; | |
2e171178 | 2102 | |
82b3e2c6 | 2103 | const SCM top_level = scm_env_top_level (env); |
73b64342 | 2104 | |
82b3e2c6 DH |
2105 | const SCM cdr_expr = SCM_CDR (expr); |
2106 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
2107 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); | |
2108 | bindings = SCM_CAR (cdr_expr); | |
2109 | check_bindings (bindings, expr); | |
2110 | transform_bindings (bindings, expr, &rvariables, &inits); | |
2111 | ||
2112 | for (variable_idx = rvariables; | |
a61f4e0c | 2113 | !scm_is_null (variable_idx); |
82b3e2c6 | 2114 | variable_idx = SCM_CDR (variable_idx)) |
73b64342 | 2115 | { |
82b3e2c6 DH |
2116 | /* The first call to scm_sym2var will look beyond the current module, |
2117 | * while the second call wont. */ | |
2118 | const SCM variable = SCM_CAR (variable_idx); | |
2119 | SCM new_variable = scm_sym2var (variable, top_level, SCM_BOOL_F); | |
7888309b | 2120 | if (scm_is_false (new_variable)) |
82b3e2c6 DH |
2121 | new_variable = scm_sym2var (variable, top_level, SCM_BOOL_T); |
2122 | SCM_SETCAR (variable_idx, new_variable); | |
73b64342 | 2123 | } |
82b3e2c6 DH |
2124 | |
2125 | SCM_SETCAR (expr, SCM_IM_BIND); | |
2126 | SCM_SETCAR (cdr_expr, scm_cons (rvariables, inits)); | |
2127 | return expr; | |
73b64342 | 2128 | } |
73b64342 | 2129 | |
b0c5d67b | 2130 | |
3b88ed2a | 2131 | SCM_SYNTAX(s_atcall_cc, "@call-with-current-continuation", scm_i_makbimacro, scm_m_cont); |
5f236208 | 2132 | SCM_GLOBAL_SYMBOL(scm_sym_atcall_cc, "@call-with-current-continuation"); |
9fbee57e | 2133 | |
4d0949ea | 2134 | static SCM |
da48db62 | 2135 | scm_m_cont (SCM expr, SCM env SCM_UNUSED) |
b0c5d67b | 2136 | { |
da48db62 DH |
2137 | const SCM cdr_expr = SCM_CDR (expr); |
2138 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
2139 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 1, s_expression, expr); | |
2140 | ||
2141 | SCM_SETCAR (expr, SCM_IM_CONT); | |
2142 | return expr; | |
b0c5d67b | 2143 | } |
b0c5d67b | 2144 | |
212e58ed DH |
2145 | static SCM |
2146 | unmemoize_atcall_cc (const SCM expr, const SCM env) | |
2147 | { | |
2148 | return scm_list_2 (scm_sym_atcall_cc, unmemoize_exprs (SCM_CDR (expr), env)); | |
2149 | } | |
2150 | ||
b0c5d67b | 2151 | |
3b88ed2a | 2152 | SCM_SYNTAX (s_at_call_with_values, "@call-with-values", scm_i_makbimacro, scm_m_at_call_with_values); |
5f236208 | 2153 | SCM_GLOBAL_SYMBOL(scm_sym_at_call_with_values, "@call-with-values"); |
b0c5d67b | 2154 | |
4d0949ea | 2155 | static SCM |
da48db62 | 2156 | scm_m_at_call_with_values (SCM expr, SCM env SCM_UNUSED) |
b0c5d67b | 2157 | { |
da48db62 DH |
2158 | const SCM cdr_expr = SCM_CDR (expr); |
2159 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
2160 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 2, s_expression, expr); | |
2161 | ||
2162 | SCM_SETCAR (expr, SCM_IM_CALL_WITH_VALUES); | |
2163 | return expr; | |
b0c5d67b | 2164 | } |
b0c5d67b | 2165 | |
212e58ed DH |
2166 | static SCM |
2167 | unmemoize_at_call_with_values (const SCM expr, const SCM env) | |
2168 | { | |
2169 | return scm_list_2 (scm_sym_at_call_with_values, | |
2170 | unmemoize_exprs (SCM_CDR (expr), env)); | |
2171 | } | |
2172 | ||
9c35c579 | 2173 | SCM_SYNTAX (s_eval_when, "eval-when", scm_makmmacro, scm_m_eval_when); |
5f236208 | 2174 | SCM_GLOBAL_SYMBOL (scm_sym_eval_when, "eval-when"); |
9c35c579 AW |
2175 | SCM_SYMBOL (sym_eval, "eval"); |
2176 | SCM_SYMBOL (sym_load, "load"); | |
2177 | ||
2178 | ||
4d0949ea | 2179 | static SCM |
9c35c579 AW |
2180 | scm_m_eval_when (SCM expr, SCM env SCM_UNUSED) |
2181 | { | |
b3501b80 | 2182 | ASSERT_SYNTAX (scm_ilength (expr) >= 3, s_bad_expression, expr); |
9c35c579 AW |
2183 | ASSERT_SYNTAX (scm_ilength (scm_cadr (expr)) > 0, s_bad_expression, expr); |
2184 | ||
2185 | if (scm_is_true (scm_memq (sym_eval, scm_cadr (expr))) | |
2186 | || scm_is_true (scm_memq (sym_load, scm_cadr (expr)))) | |
b3501b80 | 2187 | return scm_cons (SCM_IM_BEGIN, scm_cddr (expr)); |
9c35c579 AW |
2188 | |
2189 | return scm_list_1 (SCM_IM_BEGIN); | |
2190 | } | |
2191 | ||
3b88ed2a | 2192 | SCM_SYNTAX (s_gset_x, "set!", scm_i_makbimacro, scm_m_generalized_set_x); |
9fbee57e DH |
2193 | SCM_SYMBOL (scm_sym_setter, "setter"); |
2194 | ||
4d0949ea | 2195 | static SCM |
7893dbbf | 2196 | scm_m_generalized_set_x (SCM expr, SCM env) |
9fbee57e | 2197 | { |
7893dbbf | 2198 | SCM target, exp_target; |
da48db62 DH |
2199 | |
2200 | const SCM cdr_expr = SCM_CDR (expr); | |
2201 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
2202 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 2, s_expression, expr); | |
2203 | ||
2204 | target = SCM_CAR (cdr_expr); | |
a61f4e0c | 2205 | if (!scm_is_pair (target)) |
da48db62 DH |
2206 | { |
2207 | /* R5RS usage */ | |
2208 | return scm_m_set_x (expr, env); | |
2209 | } | |
9fbee57e | 2210 | else |
da48db62 DH |
2211 | { |
2212 | /* (set! (foo bar ...) baz) becomes ((setter foo) bar ... baz) */ | |
7893dbbf MV |
2213 | /* Macroexpanding the target might return things of the form |
2214 | (begin <atom>). In that case, <atom> must be a symbol or a | |
2215 | variable and we memoize to (set! <atom> ...). | |
2216 | */ | |
2b189e65 | 2217 | exp_target = macroexp (target, env); |
bc36d050 | 2218 | if (scm_is_eq (SCM_CAR (exp_target), SCM_IM_BEGIN) |
a61f4e0c MV |
2219 | && !scm_is_null (SCM_CDR (exp_target)) |
2220 | && scm_is_null (SCM_CDDR (exp_target))) | |
7893dbbf MV |
2221 | { |
2222 | exp_target= SCM_CADR (exp_target); | |
cc95e00a | 2223 | ASSERT_SYNTAX_2 (scm_is_symbol (exp_target) |
6d1a2e9f MV |
2224 | || SCM_VARIABLEP (exp_target), |
2225 | s_bad_variable, exp_target, expr); | |
7893dbbf MV |
2226 | return scm_cons (SCM_IM_SET_X, scm_cons (exp_target, |
2227 | SCM_CDR (cdr_expr))); | |
2228 | } | |
2229 | else | |
2230 | { | |
2231 | const SCM setter_proc_tail = scm_list_1 (SCM_CAR (target)); | |
2232 | const SCM setter_proc = scm_cons_source (expr, scm_sym_setter, | |
2233 | setter_proc_tail); | |
da48db62 | 2234 | |
7893dbbf MV |
2235 | const SCM cddr_expr = SCM_CDR (cdr_expr); |
2236 | const SCM setter_args = scm_append_x (scm_list_2 (SCM_CDR (target), | |
2237 | cddr_expr)); | |
da48db62 | 2238 | |
7893dbbf MV |
2239 | SCM_SETCAR (expr, setter_proc); |
2240 | SCM_SETCDR (expr, setter_args); | |
2241 | return expr; | |
2242 | } | |
da48db62 | 2243 | } |
9fbee57e DH |
2244 | } |
2245 | ||
2246 | ||
a4aa2134 DH |
2247 | /* @slot-ref is bound privately in the (oop goops) module from goops.c. As |
2248 | * soon as the module system allows us to more freely create bindings in | |
2249 | * arbitrary modules during the startup phase, the code from goops.c should be | |
2250 | * moved here. */ | |
212e58ed | 2251 | |
4d0949ea LC |
2252 | SCM_SYNTAX (s_atslot_ref, "@slot-ref", scm_i_makbimacro, scm_m_atslot_ref); |
2253 | SCM_SYNTAX (s_atslot_set_x, "@slot-set!", scm_i_makbimacro, scm_m_atslot_set_x); | |
212e58ed DH |
2254 | SCM_SYMBOL (sym_atslot_ref, "@slot-ref"); |
2255 | ||
4d0949ea | 2256 | static SCM |
9a848baf | 2257 | scm_m_atslot_ref (SCM expr, SCM env SCM_UNUSED) |
9fbee57e | 2258 | { |
9a848baf DH |
2259 | SCM slot_nr; |
2260 | ||
2261 | const SCM cdr_expr = SCM_CDR (expr); | |
2262 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
2263 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 2, s_expression, expr); | |
2264 | slot_nr = SCM_CADR (cdr_expr); | |
e11e83f3 | 2265 | ASSERT_SYNTAX_2 (SCM_I_INUMP (slot_nr), s_bad_slot_number, slot_nr, expr); |
9fbee57e | 2266 | |
9a848baf | 2267 | SCM_SETCAR (expr, SCM_IM_SLOT_REF); |
e7313a9d | 2268 | SCM_SETCDR (cdr_expr, slot_nr); |
9a848baf DH |
2269 | return expr; |
2270 | } | |
9fbee57e | 2271 | |
212e58ed DH |
2272 | static SCM |
2273 | unmemoize_atslot_ref (const SCM expr, const SCM env) | |
2274 | { | |
2275 | const SCM instance = SCM_CADR (expr); | |
2276 | const SCM um_instance = unmemoize_expression (instance, env); | |
2277 | const SCM slot_nr = SCM_CDDR (expr); | |
2278 | return scm_list_3 (sym_atslot_ref, um_instance, slot_nr); | |
2279 | } | |
2280 | ||
9fbee57e | 2281 | |
a4aa2134 DH |
2282 | /* @slot-set! is bound privately in the (oop goops) module from goops.c. As |
2283 | * soon as the module system allows us to more freely create bindings in | |
2284 | * arbitrary modules during the startup phase, the code from goops.c should be | |
2285 | * moved here. */ | |
212e58ed DH |
2286 | |
2287 | SCM_SYMBOL (sym_atslot_set_x, "@slot-set!"); | |
2288 | ||
4d0949ea | 2289 | static SCM |
9a848baf | 2290 | scm_m_atslot_set_x (SCM expr, SCM env SCM_UNUSED) |
9fbee57e | 2291 | { |
9a848baf DH |
2292 | SCM slot_nr; |
2293 | ||
2294 | const SCM cdr_expr = SCM_CDR (expr); | |
2295 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
2296 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 3, s_expression, expr); | |
2297 | slot_nr = SCM_CADR (cdr_expr); | |
e11e83f3 | 2298 | ASSERT_SYNTAX_2 (SCM_I_INUMP (slot_nr), s_bad_slot_number, slot_nr, expr); |
9a848baf DH |
2299 | |
2300 | SCM_SETCAR (expr, SCM_IM_SLOT_SET_X); | |
2301 | return expr; | |
9fbee57e | 2302 | } |
9fbee57e | 2303 | |
212e58ed DH |
2304 | static SCM |
2305 | unmemoize_atslot_set_x (const SCM expr, const SCM env) | |
2306 | { | |
2307 | const SCM cdr_expr = SCM_CDR (expr); | |
2308 | const SCM instance = SCM_CAR (cdr_expr); | |
2309 | const SCM um_instance = unmemoize_expression (instance, env); | |
2310 | const SCM cddr_expr = SCM_CDR (cdr_expr); | |
2311 | const SCM slot_nr = SCM_CAR (cddr_expr); | |
2312 | const SCM cdddr_expr = SCM_CDR (cddr_expr); | |
2313 | const SCM value = SCM_CAR (cdddr_expr); | |
2314 | const SCM um_value = unmemoize_expression (value, env); | |
2315 | return scm_list_4 (sym_atslot_set_x, um_instance, slot_nr, um_value); | |
2316 | } | |
2317 | ||
9fbee57e DH |
2318 | |
2319 | #if SCM_ENABLE_ELISP | |
2320 | ||
70c1c108 DH |
2321 | static const char s_defun[] = "Symbol's function definition is void"; |
2322 | ||
3b88ed2a | 2323 | SCM_SYNTAX (s_nil_cond, "nil-cond", scm_i_makbimacro, scm_m_nil_cond); |
9fbee57e | 2324 | |
70c1c108 DH |
2325 | /* nil-cond expressions have the form |
2326 | * (nil-cond COND VAL COND VAL ... ELSEVAL) */ | |
4d0949ea | 2327 | static SCM |
70c1c108 | 2328 | scm_m_nil_cond (SCM expr, SCM env SCM_UNUSED) |
9fbee57e | 2329 | { |
70c1c108 DH |
2330 | const long length = scm_ilength (SCM_CDR (expr)); |
2331 | ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); | |
2332 | ASSERT_SYNTAX (length >= 1 && (length % 2) == 1, s_expression, expr); | |
2333 | ||
2334 | SCM_SETCAR (expr, SCM_IM_NIL_COND); | |
2335 | return expr; | |
9fbee57e DH |
2336 | } |
2337 | ||
2338 | ||
3b88ed2a | 2339 | SCM_SYNTAX (s_atfop, "@fop", scm_i_makbimacro, scm_m_atfop); |
9fbee57e | 2340 | |
70c1c108 DH |
2341 | /* The @fop-macro handles procedure and macro applications for elisp. The |
2342 | * input expression must have the form | |
2343 | * (@fop <var> (transformer-macro <expr> ...)) | |
2344 | * where <var> must be a symbol. The expression is transformed into the | |
2345 | * memoized form of either | |
2346 | * (apply <un-aliased var> (transformer-macro <expr> ...)) | |
2347 | * if the value of var (across all aliasing) is not a macro, or | |
2348 | * (<un-aliased var> <expr> ...) | |
2349 | * if var is a macro. */ | |
4d0949ea | 2350 | static SCM |
70c1c108 | 2351 | scm_m_atfop (SCM expr, SCM env SCM_UNUSED) |
9fbee57e | 2352 | { |
70c1c108 DH |
2353 | SCM location; |
2354 | SCM symbol; | |
2355 | ||
2356 | const SCM cdr_expr = SCM_CDR (expr); | |
2357 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
2358 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 1, s_missing_expression, expr); | |
2359 | ||
2360 | symbol = SCM_CAR (cdr_expr); | |
cc95e00a | 2361 | ASSERT_SYNTAX_2 (scm_is_symbol (symbol), s_bad_variable, symbol, expr); |
70c1c108 DH |
2362 | |
2363 | location = scm_symbol_fref (symbol); | |
2364 | ASSERT_SYNTAX_2 (SCM_VARIABLEP (location), s_defun, symbol, expr); | |
2365 | ||
2366 | /* The elisp function `defalias' allows to define aliases for symbols. To | |
2367 | * look up such definitions, the chain of symbol definitions has to be | |
2368 | * followed up to the terminal symbol. */ | |
cc95e00a | 2369 | while (scm_is_symbol (SCM_VARIABLE_REF (location))) |
9fbee57e | 2370 | { |
70c1c108 DH |
2371 | const SCM alias = SCM_VARIABLE_REF (location); |
2372 | location = scm_symbol_fref (alias); | |
2373 | ASSERT_SYNTAX_2 (SCM_VARIABLEP (location), s_defun, symbol, expr); | |
9fbee57e | 2374 | } |
70c1c108 DH |
2375 | |
2376 | /* Memoize the value location belonging to the terminal symbol. */ | |
2377 | SCM_SETCAR (cdr_expr, location); | |
2378 | ||
2379 | if (!SCM_MACROP (SCM_VARIABLE_REF (location))) | |
9fbee57e | 2380 | { |
70c1c108 DH |
2381 | /* Since the location does not contain a macro, the form is a procedure |
2382 | * application. Replace `@fop' by `@apply' and transform the expression | |
2383 | * including the `transformer-macro'. */ | |
2384 | SCM_SETCAR (expr, SCM_IM_APPLY); | |
2385 | return expr; | |
2386 | } | |
2387 | else | |
2388 | { | |
2389 | /* Since the location contains a macro, the arguments should not be | |
2390 | * transformed, so the `transformer-macro' is cut out. The resulting | |
2391 | * expression starts with the memoized variable, that is at the cdr of | |
2392 | * the input expression. */ | |
2393 | SCM_SETCDR (cdr_expr, SCM_CDADR (cdr_expr)); | |
2394 | return cdr_expr; | |
9fbee57e | 2395 | } |
9fbee57e DH |
2396 | } |
2397 | ||
2398 | #endif /* SCM_ENABLE_ELISP */ | |
2399 | ||
2400 | ||
212e58ed DH |
2401 | static SCM |
2402 | unmemoize_builtin_macro (const SCM expr, const SCM env) | |
2403 | { | |
2404 | switch (ISYMNUM (SCM_CAR (expr))) | |
2405 | { | |
2406 | case (ISYMNUM (SCM_IM_AND)): | |
2407 | return unmemoize_and (expr, env); | |
2408 | ||
2409 | case (ISYMNUM (SCM_IM_BEGIN)): | |
2410 | return unmemoize_begin (expr, env); | |
2411 | ||
2412 | case (ISYMNUM (SCM_IM_CASE)): | |
2413 | return unmemoize_case (expr, env); | |
2414 | ||
2415 | case (ISYMNUM (SCM_IM_COND)): | |
2416 | return unmemoize_cond (expr, env); | |
2417 | ||
2418 | case (ISYMNUM (SCM_IM_DELAY)): | |
2419 | return unmemoize_delay (expr, env); | |
2420 | ||
2421 | case (ISYMNUM (SCM_IM_DO)): | |
2422 | return unmemoize_do (expr, env); | |
2423 | ||
2424 | case (ISYMNUM (SCM_IM_IF)): | |
2425 | return unmemoize_if (expr, env); | |
2426 | ||
2427 | case (ISYMNUM (SCM_IM_LAMBDA)): | |
2428 | return unmemoize_lambda (expr, env); | |
2429 | ||
2430 | case (ISYMNUM (SCM_IM_LET)): | |
2431 | return unmemoize_let (expr, env); | |
2432 | ||
2433 | case (ISYMNUM (SCM_IM_LETREC)): | |
2434 | return unmemoize_letrec (expr, env); | |
2435 | ||
2436 | case (ISYMNUM (SCM_IM_LETSTAR)): | |
2437 | return unmemoize_letstar (expr, env); | |
2438 | ||
2439 | case (ISYMNUM (SCM_IM_OR)): | |
2440 | return unmemoize_or (expr, env); | |
2441 | ||
2442 | case (ISYMNUM (SCM_IM_QUOTE)): | |
2443 | return unmemoize_quote (expr, env); | |
2444 | ||
2445 | case (ISYMNUM (SCM_IM_SET_X)): | |
2446 | return unmemoize_set_x (expr, env); | |
2447 | ||
2448 | case (ISYMNUM (SCM_IM_APPLY)): | |
2449 | return unmemoize_apply (expr, env); | |
2450 | ||
2451 | case (ISYMNUM (SCM_IM_BIND)): | |
2452 | return unmemoize_exprs (expr, env); /* FIXME */ | |
2453 | ||
2454 | case (ISYMNUM (SCM_IM_CONT)): | |
2455 | return unmemoize_atcall_cc (expr, env); | |
2456 | ||
2457 | case (ISYMNUM (SCM_IM_CALL_WITH_VALUES)): | |
2458 | return unmemoize_at_call_with_values (expr, env); | |
2459 | ||
212e58ed DH |
2460 | case (ISYMNUM (SCM_IM_SLOT_REF)): |
2461 | return unmemoize_atslot_ref (expr, env); | |
2462 | ||
2463 | case (ISYMNUM (SCM_IM_SLOT_SET_X)): | |
2464 | return unmemoize_atslot_set_x (expr, env); | |
2465 | ||
2466 | case (ISYMNUM (SCM_IM_NIL_COND)): | |
2467 | return unmemoize_exprs (expr, env); /* FIXME */ | |
2468 | ||
2469 | default: | |
2470 | return unmemoize_exprs (expr, env); /* FIXME */ | |
2471 | } | |
2472 | } | |
2473 | ||
2474 | ||
9fcf3cbb DH |
2475 | /* scm_i_unmemocopy_expr and scm_i_unmemocopy_body take a memoized expression |
2476 | * respectively a memoized body together with its environment and rewrite it | |
2477 | * to its original form. Thus, these functions are the inversion of the | |
2478 | * rewrite rules above. The procedure is not optimized for speed. It's used | |
2479 | * in scm_i_unmemoize_expr, scm_procedure_source, macro_print and scm_iprin1. | |
212e58ed DH |
2480 | * |
2481 | * Unmemoizing is not a reliable process. You cannot in general expect to get | |
2482 | * the original source back. | |
2483 | * | |
2484 | * However, GOOPS currently relies on this for method compilation. This ought | |
2485 | * to change. */ | |
2486 | ||
2487 | SCM | |
9fcf3cbb DH |
2488 | scm_i_unmemocopy_expr (SCM expr, SCM env) |
2489 | { | |
2490 | const SCM source_properties = scm_whash_lookup (scm_source_whash, expr); | |
2491 | const SCM um_expr = unmemoize_expression (expr, env); | |
2492 | ||
7888309b | 2493 | if (scm_is_true (source_properties)) |
9fcf3cbb DH |
2494 | scm_whash_insert (scm_source_whash, um_expr, source_properties); |
2495 | ||
2496 | return um_expr; | |
2497 | } | |
2498 | ||
2499 | SCM | |
2500 | scm_i_unmemocopy_body (SCM forms, SCM env) | |
212e58ed DH |
2501 | { |
2502 | const SCM source_properties = scm_whash_lookup (scm_source_whash, forms); | |
2503 | const SCM um_forms = unmemoize_exprs (forms, env); | |
2504 | ||
7888309b | 2505 | if (scm_is_true (source_properties)) |
212e58ed DH |
2506 | scm_whash_insert (scm_source_whash, um_forms, source_properties); |
2507 | ||
2508 | return um_forms; | |
2509 | } | |
2510 | ||
2511 | ||
434f2f7a | 2512 | #if (SCM_ENABLE_DEPRECATED == 1) |
f58c472a | 2513 | |
b3ce13b6 | 2514 | static SCM scm_m_undefine (SCM expr, SCM env); |
f58c472a DH |
2515 | |
2516 | SCM_SYNTAX (s_undefine, "undefine", scm_makacro, scm_m_undefine); | |
2517 | ||
b3ce13b6 | 2518 | static SCM |
70c1c108 | 2519 | scm_m_undefine (SCM expr, SCM env) |
f58c472a | 2520 | { |
70c1c108 DH |
2521 | SCM variable; |
2522 | SCM location; | |
2523 | ||
2524 | const SCM cdr_expr = SCM_CDR (expr); | |
2525 | ASSERT_SYNTAX (SCM_TOP_LEVEL (env), "Bad undefine placement in", expr); | |
2526 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
2527 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 1, s_expression, expr); | |
2528 | ||
2b189e65 MV |
2529 | scm_c_issue_deprecation_warning |
2530 | ("`undefine' is deprecated.\n"); | |
2531 | ||
70c1c108 | 2532 | variable = SCM_CAR (cdr_expr); |
cc95e00a | 2533 | ASSERT_SYNTAX_2 (scm_is_symbol (variable), s_bad_variable, variable, expr); |
70c1c108 | 2534 | location = scm_sym2var (variable, scm_env_top_level (env), SCM_BOOL_F); |
7888309b | 2535 | ASSERT_SYNTAX_2 (scm_is_true (location) |
70c1c108 DH |
2536 | && !SCM_UNBNDP (SCM_VARIABLE_REF (location)), |
2537 | "variable already unbound ", variable, expr); | |
2538 | SCM_VARIABLE_SET (location, SCM_UNDEFINED); | |
f58c472a | 2539 | return SCM_UNSPECIFIED; |
f58c472a DH |
2540 | } |
2541 | ||
b3ce13b6 | 2542 | #endif /* SCM_ENABLE_DEPRECATED */ |
60a49842 | 2543 | |
434f2f7a | 2544 | |
b3ce13b6 | 2545 | \f |
6f81708a DH |
2546 | /*****************************************************************************/ |
2547 | /*****************************************************************************/ | |
2548 | /* The definitions for execution start here. */ | |
2549 | /*****************************************************************************/ | |
2550 | /*****************************************************************************/ | |
2551 | ||
2552 | SCM_GLOBAL_SYMBOL (scm_sym_enter_frame, "enter-frame"); | |
2553 | SCM_GLOBAL_SYMBOL (scm_sym_apply_frame, "apply-frame"); | |
2554 | SCM_GLOBAL_SYMBOL (scm_sym_exit_frame, "exit-frame"); | |
72f19c26 | 2555 | SCM_GLOBAL_SYMBOL (scm_sym_memoize_symbol, "memoize-symbol"); |
6f81708a | 2556 | SCM_GLOBAL_SYMBOL (scm_sym_trace, "trace"); |
7c9c0169 | 2557 | SCM_SYMBOL (sym_instead, "instead"); |
6f81708a DH |
2558 | |
2559 | /* A function object to implement "apply" for non-closure functions. */ | |
2560 | static SCM f_apply; | |
2561 | /* An endless list consisting of #<undefined> objects: */ | |
2562 | static SCM undefineds; | |
2563 | ||
2564 | ||
2565 | int | |
6e8d25a6 | 2566 | scm_badargsp (SCM formals, SCM args) |
0f2d19dd | 2567 | { |
a61f4e0c | 2568 | while (!scm_is_null (formals)) |
0f2d19dd | 2569 | { |
a61f4e0c | 2570 | if (!scm_is_pair (formals)) |
ff467021 | 2571 | return 0; |
a61f4e0c | 2572 | if (scm_is_null (args)) |
ff467021 | 2573 | return 1; |
0f2d19dd JB |
2574 | formals = SCM_CDR (formals); |
2575 | args = SCM_CDR (args); | |
2576 | } | |
a61f4e0c | 2577 | return !scm_is_null (args) ? 1 : 0; |
0f2d19dd | 2578 | } |
a392ee15 | 2579 | |
0f2d19dd | 2580 | \f |
62360b89 | 2581 | |
0ee05b85 | 2582 | /* The evaluator contains a plethora of EVAL symbols. |
62360b89 | 2583 | * |
62360b89 | 2584 | * |
385609b9 | 2585 | * SCM_I_EVALIM is used when it is known that the expression is an |
62360b89 | 2586 | * immediate. (This macro never calls an evaluator.) |
434f2f7a | 2587 | * |
0ee05b85 | 2588 | * SCM_I_XEVAL evaluates an expression that is expected to have its symbols already |
434f2f7a DH |
2589 | * memoized. Expressions that are not of the form '(<form> <form> ...)' are |
2590 | * evaluated inline without calling an evaluator. | |
2591 | * | |
0ee05b85 HWN |
2592 | * This macro uses ceval or deval depending on its 3rd argument. |
2593 | * | |
2594 | * SCM_I_XEVALCAR evaluates the car of an expression 'X:(Y:<form> <form> ...)', | |
434f2f7a DH |
2595 | * potentially replacing a symbol at the position Y:<form> by its memoized |
2596 | * variable. If Y:<form> is not of the form '(<form> <form> ...)', the | |
2597 | * evaluation is performed inline without calling an evaluator. | |
62360b89 | 2598 | * |
0ee05b85 | 2599 | * This macro uses ceval or deval depending on its 3rd argument. |
62360b89 | 2600 | * |
62360b89 DH |
2601 | */ |
2602 | ||
385609b9 | 2603 | #define SCM_I_EVALIM2(x) \ |
bc36d050 | 2604 | ((scm_is_eq ((x), SCM_EOL) \ |
62360b89 DH |
2605 | ? syntax_error (s_empty_combination, (x), SCM_UNDEFINED), 0 \ |
2606 | : 0), \ | |
2607 | (x)) | |
2608 | ||
385609b9 | 2609 | #define SCM_I_EVALIM(x, env) (SCM_ILOCP (x) \ |
434f2f7a | 2610 | ? *scm_ilookup ((x), (env)) \ |
385609b9 | 2611 | : SCM_I_EVALIM2(x)) |
62360b89 | 2612 | |
0ee05b85 | 2613 | #define SCM_I_XEVAL(x, env, debug_p) \ |
434f2f7a | 2614 | (SCM_IMP (x) \ |
385609b9 | 2615 | ? SCM_I_EVALIM2 (x) \ |
434f2f7a DH |
2616 | : (SCM_VARIABLEP (x) \ |
2617 | ? SCM_VARIABLE_REF (x) \ | |
a61f4e0c | 2618 | : (scm_is_pair (x) \ |
0ee05b85 | 2619 | ? (debug_p \ |
434f2f7a DH |
2620 | ? deval ((x), (env)) \ |
2621 | : ceval ((x), (env))) \ | |
2622 | : (x)))) | |
2623 | ||
0ee05b85 | 2624 | #define SCM_I_XEVALCAR(x, env, debug_p) \ |
434f2f7a | 2625 | (SCM_IMP (SCM_CAR (x)) \ |
385609b9 | 2626 | ? SCM_I_EVALIM (SCM_CAR (x), (env)) \ |
434f2f7a DH |
2627 | : (SCM_VARIABLEP (SCM_CAR (x)) \ |
2628 | ? SCM_VARIABLE_REF (SCM_CAR (x)) \ | |
a61f4e0c | 2629 | : (scm_is_pair (SCM_CAR (x)) \ |
0ee05b85 | 2630 | ? (debug_p \ |
434f2f7a DH |
2631 | ? deval (SCM_CAR (x), (env)) \ |
2632 | : ceval (SCM_CAR (x), (env))) \ | |
cc95e00a | 2633 | : (!scm_is_symbol (SCM_CAR (x)) \ |
434f2f7a DH |
2634 | ? SCM_CAR (x) \ |
2635 | : *scm_lookupcar ((x), (env), 1))))) | |
2636 | ||
d1138028 | 2637 | scm_i_pthread_mutex_t source_mutex; |
62360b89 DH |
2638 | |
2639 | ||
e5156567 DH |
2640 | /* Lookup a given local variable in an environment. The local variable is |
2641 | * given as an iloc, that is a triple <frame, binding, last?>, where frame | |
2642 | * indicates the relative number of the environment frame (counting upwards | |
2643 | * from the innermost environment frame), binding indicates the number of the | |
2644 | * binding within the frame, and last? (which is extracted from the iloc using | |
2645 | * the macro SCM_ICDRP) indicates whether the binding forms the binding at the | |
2646 | * very end of the improper list of bindings. */ | |
2647 | SCM * | |
2648 | scm_ilookup (SCM iloc, SCM env) | |
2649 | { | |
2650 | unsigned int frame_nr = SCM_IFRAME (iloc); | |
2651 | unsigned int binding_nr = SCM_IDIST (iloc); | |
2652 | SCM frames = env; | |
2653 | SCM bindings; | |
2654 | ||
2655 | for (; 0 != frame_nr; --frame_nr) | |
2656 | frames = SCM_CDR (frames); | |
2657 | ||
2658 | bindings = SCM_CAR (frames); | |
2659 | for (; 0 != binding_nr; --binding_nr) | |
2660 | bindings = SCM_CDR (bindings); | |
2661 | ||
2662 | if (SCM_ICDRP (iloc)) | |
2663 | return SCM_CDRLOC (bindings); | |
2664 | return SCM_CARLOC (SCM_CDR (bindings)); | |
2665 | } | |
2666 | ||
2667 | ||
2668 | SCM_SYMBOL (scm_unbound_variable_key, "unbound-variable"); | |
2669 | ||
2d0c133f MV |
2670 | /* Call this for variables that are unfound. |
2671 | */ | |
e5156567 DH |
2672 | static void |
2673 | error_unbound_variable (SCM symbol) | |
2674 | { | |
2675 | scm_error (scm_unbound_variable_key, NULL, | |
2676 | "Unbound variable: ~S", | |
2677 | scm_list_1 (symbol), SCM_BOOL_F); | |
2678 | } | |
2679 | ||
2d0c133f MV |
2680 | /* Call this for variables that are found but contain SCM_UNDEFINED. |
2681 | */ | |
2682 | static void | |
2683 | error_defined_variable (SCM symbol) | |
2684 | { | |
2685 | /* We use the 'unbound-variable' key here as well, since it | |
2686 | basically is the same kind of error, with a slight variation in | |
2687 | the displayed message. | |
2688 | */ | |
2689 | scm_error (scm_unbound_variable_key, NULL, | |
a03bad87 | 2690 | "Variable used before given a value: ~S", |
2d0c133f MV |
2691 | scm_list_1 (symbol), SCM_BOOL_F); |
2692 | } | |
2693 | ||
e5156567 DH |
2694 | |
2695 | /* The Lookup Car Race | |
2696 | - by Eva Luator | |
2697 | ||
2698 | Memoization of variables and special forms is done while executing | |
2699 | the code for the first time. As long as there is only one thread | |
2700 | everything is fine, but as soon as two threads execute the same | |
2701 | code concurrently `for the first time' they can come into conflict. | |
2702 | ||
2703 | This memoization includes rewriting variable references into more | |
2704 | efficient forms and expanding macros. Furthermore, macro expansion | |
2705 | includes `compiling' special forms like `let', `cond', etc. into | |
2706 | tree-code instructions. | |
2707 | ||
2708 | There shouldn't normally be a problem with memoizing local and | |
2709 | global variable references (into ilocs and variables), because all | |
2710 | threads will mutate the code in *exactly* the same way and (if I | |
2711 | read the C code correctly) it is not possible to observe a half-way | |
2712 | mutated cons cell. The lookup procedure can handle this | |
2713 | transparently without any critical sections. | |
2714 | ||
2715 | It is different with macro expansion, because macro expansion | |
2716 | happens outside of the lookup procedure and can't be | |
2717 | undone. Therefore the lookup procedure can't cope with it. It has | |
2718 | to indicate failure when it detects a lost race and hope that the | |
2719 | caller can handle it. Luckily, it turns out that this is the case. | |
2720 | ||
2721 | An example to illustrate this: Suppose that the following form will | |
2722 | be memoized concurrently by two threads | |
2723 | ||
2724 | (let ((x 12)) x) | |
2725 | ||
2726 | Let's first examine the lookup of X in the body. The first thread | |
2727 | decides that it has to find the symbol "x" in the environment and | |
2728 | starts to scan it. Then the other thread takes over and actually | |
2729 | overtakes the first. It looks up "x" and substitutes an | |
2730 | appropriate iloc for it. Now the first thread continues and | |
2731 | completes its lookup. It comes to exactly the same conclusions as | |
2732 | the second one and could - without much ado - just overwrite the | |
2733 | iloc with the same iloc. | |
2734 | ||
2735 | But let's see what will happen when the race occurs while looking | |
2736 | up the symbol "let" at the start of the form. It could happen that | |
2737 | the second thread interrupts the lookup of the first thread and not | |
2738 | only substitutes a variable for it but goes right ahead and | |
2739 | replaces it with the compiled form (#@let* (x 12) x). Now, when | |
2740 | the first thread completes its lookup, it would replace the #@let* | |
2741 | with a variable containing the "let" binding, effectively reverting | |
2742 | the form to (let (x 12) x). This is wrong. It has to detect that | |
2743 | it has lost the race and the evaluator has to reconsider the | |
2744 | changed form completely. | |
2745 | ||
2746 | This race condition could be resolved with some kind of traffic | |
2747 | light (like mutexes) around scm_lookupcar, but I think that it is | |
2748 | best to avoid them in this case. They would serialize memoization | |
2749 | completely and because lookup involves calling arbitrary Scheme | |
2750 | code (via the lookup-thunk), threads could be blocked for an | |
2751 | arbitrary amount of time or even deadlock. But with the current | |
2752 | solution a lot of unnecessary work is potentially done. */ | |
2753 | ||
2754 | /* SCM_LOOKUPCAR1 is what SCM_LOOKUPCAR used to be but is allowed to | |
2755 | return NULL to indicate a failed lookup due to some race conditions | |
2756 | between threads. This only happens when VLOC is the first cell of | |
2757 | a special form that will eventually be memoized (like `let', etc.) | |
2758 | In that case the whole lookup is bogus and the caller has to | |
2759 | reconsider the complete special form. | |
2760 | ||
2761 | SCM_LOOKUPCAR is still there, of course. It just calls | |
2762 | SCM_LOOKUPCAR1 and aborts on receiving NULL. So SCM_LOOKUPCAR | |
2763 | should only be called when it is known that VLOC is not the first | |
2764 | pair of a special form. Otherwise, use SCM_LOOKUPCAR1 and check | |
2765 | for NULL. I think I've found the only places where this | |
2766 | applies. */ | |
2767 | ||
2768 | static SCM * | |
2769 | scm_lookupcar1 (SCM vloc, SCM genv, int check) | |
2770 | { | |
2771 | SCM env = genv; | |
2772 | register SCM *al, fl, var = SCM_CAR (vloc); | |
2773 | register SCM iloc = SCM_ILOC00; | |
2774 | for (; SCM_NIMP (env); env = SCM_CDR (env)) | |
2775 | { | |
a61f4e0c | 2776 | if (!scm_is_pair (SCM_CAR (env))) |
e5156567 DH |
2777 | break; |
2778 | al = SCM_CARLOC (env); | |
2779 | for (fl = SCM_CAR (*al); SCM_NIMP (fl); fl = SCM_CDR (fl)) | |
2780 | { | |
a61f4e0c | 2781 | if (!scm_is_pair (fl)) |
e5156567 | 2782 | { |
bc36d050 | 2783 | if (scm_is_eq (fl, var)) |
e5156567 | 2784 | { |
bc36d050 | 2785 | if (!scm_is_eq (SCM_CAR (vloc), var)) |
e5156567 DH |
2786 | goto race; |
2787 | SCM_SET_CELL_WORD_0 (vloc, SCM_UNPACK (iloc) + SCM_ICDR); | |
2788 | return SCM_CDRLOC (*al); | |
2789 | } | |
2790 | else | |
2791 | break; | |
2792 | } | |
2793 | al = SCM_CDRLOC (*al); | |
bc36d050 | 2794 | if (scm_is_eq (SCM_CAR (fl), var)) |
e5156567 DH |
2795 | { |
2796 | if (SCM_UNBNDP (SCM_CAR (*al))) | |
2d0c133f | 2797 | error_defined_variable (var); |
bc36d050 | 2798 | if (!scm_is_eq (SCM_CAR (vloc), var)) |
e5156567 DH |
2799 | goto race; |
2800 | SCM_SETCAR (vloc, iloc); | |
2801 | return SCM_CARLOC (*al); | |
2802 | } | |
2803 | iloc = SCM_PACK (SCM_UNPACK (iloc) + SCM_IDINC); | |
2804 | } | |
2805 | iloc = SCM_PACK ((~SCM_IDSTMSK) & (SCM_UNPACK(iloc) + SCM_IFRINC)); | |
2806 | } | |
2807 | { | |
2808 | SCM top_thunk, real_var; | |
2809 | if (SCM_NIMP (env)) | |
2810 | { | |
2811 | top_thunk = SCM_CAR (env); /* env now refers to a | |
2812 | top level env thunk */ | |
2813 | env = SCM_CDR (env); | |
2814 | } | |
2815 | else | |
2816 | top_thunk = SCM_BOOL_F; | |
2817 | real_var = scm_sym2var (var, top_thunk, SCM_BOOL_F); | |
7888309b | 2818 | if (scm_is_false (real_var)) |
e5156567 DH |
2819 | goto errout; |
2820 | ||
a61f4e0c | 2821 | if (!scm_is_null (env) || SCM_UNBNDP (SCM_VARIABLE_REF (real_var))) |
e5156567 DH |
2822 | { |
2823 | errout: | |
2824 | if (check) | |
2825 | { | |
a61f4e0c | 2826 | if (scm_is_null (env)) |
e5156567 DH |
2827 | error_unbound_variable (var); |
2828 | else | |
2829 | scm_misc_error (NULL, "Damaged environment: ~S", | |
2830 | scm_list_1 (var)); | |
2831 | } | |
2832 | else | |
2833 | { | |
2834 | /* A variable could not be found, but we shall | |
2835 | not throw an error. */ | |
2836 | static SCM undef_object = SCM_UNDEFINED; | |
2837 | return &undef_object; | |
2838 | } | |
2839 | } | |
2840 | ||
bc36d050 | 2841 | if (!scm_is_eq (SCM_CAR (vloc), var)) |
e5156567 DH |
2842 | { |
2843 | /* Some other thread has changed the very cell we are working | |
2844 | on. In effect, it must have done our job or messed it up | |
2845 | completely. */ | |
2846 | race: | |
2847 | var = SCM_CAR (vloc); | |
2848 | if (SCM_VARIABLEP (var)) | |
2849 | return SCM_VARIABLE_LOC (var); | |
2850 | if (SCM_ILOCP (var)) | |
2851 | return scm_ilookup (var, genv); | |
2852 | /* We can't cope with anything else than variables and ilocs. When | |
2853 | a special form has been memoized (i.e. `let' into `#@let') we | |
2854 | return NULL and expect the calling function to do the right | |
2855 | thing. For the evaluator, this means going back and redoing | |
2856 | the dispatch on the car of the form. */ | |
2857 | return NULL; | |
2858 | } | |
2859 | ||
2860 | SCM_SETCAR (vloc, real_var); | |
2861 | return SCM_VARIABLE_LOC (real_var); | |
2862 | } | |
2863 | } | |
2864 | ||
2865 | SCM * | |
2866 | scm_lookupcar (SCM vloc, SCM genv, int check) | |
2867 | { | |
2868 | SCM *loc = scm_lookupcar1 (vloc, genv, check); | |
2869 | if (loc == NULL) | |
2870 | abort (); | |
2871 | return loc; | |
2872 | } | |
2873 | ||
2874 | ||
36245b66 DH |
2875 | /* During execution, look up a symbol in the top level of the given local |
2876 | * environment and return the corresponding variable object. If no binding | |
2877 | * for the symbol can be found, an 'Unbound variable' error is signalled. */ | |
2878 | static SCM | |
2879 | lazy_memoize_variable (const SCM symbol, const SCM environment) | |
2880 | { | |
2881 | const SCM top_level = scm_env_top_level (environment); | |
2882 | const SCM variable = scm_sym2var (symbol, top_level, SCM_BOOL_F); | |
2883 | ||
7888309b | 2884 | if (scm_is_false (variable)) |
36245b66 DH |
2885 | error_unbound_variable (symbol); |
2886 | else | |
2887 | return variable; | |
2888 | } | |
2889 | ||
2890 | ||
62360b89 DH |
2891 | SCM |
2892 | scm_eval_car (SCM pair, SCM env) | |
2893 | { | |
0ee05b85 | 2894 | return SCM_I_XEVALCAR (pair, env, scm_debug_mode_p); |
6dbd0af5 | 2895 | } |
c4ac4d88 | 2896 | |
d0b07b5d | 2897 | |
9de33deb MD |
2898 | SCM |
2899 | scm_eval_body (SCM code, SCM env) | |
2900 | { | |
2901 | SCM next; | |
434f2f7a | 2902 | |
9de33deb | 2903 | again: |
01f11e02 | 2904 | next = SCM_CDR (code); |
a61f4e0c | 2905 | while (!scm_is_null (next)) |
9de33deb MD |
2906 | { |
2907 | if (SCM_IMP (SCM_CAR (code))) | |
2908 | { | |
2909 | if (SCM_ISYMP (SCM_CAR (code))) | |
2910 | { | |
cce0e9c8 | 2911 | scm_dynwind_begin (0); |
2b829bbb | 2912 | scm_i_dynwind_pthread_mutex_lock (&source_mutex); |
9bc4701c MD |
2913 | /* check for race condition */ |
2914 | if (SCM_ISYMP (SCM_CAR (code))) | |
9d4bf6d3 | 2915 | m_expand_body (code, env); |
cce0e9c8 | 2916 | scm_dynwind_end (); |
9de33deb MD |
2917 | goto again; |
2918 | } | |
2919 | } | |
2920 | else | |
0ee05b85 | 2921 | SCM_I_XEVAL (SCM_CAR (code), env, scm_debug_mode_p); |
9de33deb | 2922 | code = next; |
01f11e02 | 2923 | next = SCM_CDR (code); |
9de33deb | 2924 | } |
0ee05b85 | 2925 | return SCM_I_XEVALCAR (code, env, scm_debug_mode_p); |
9de33deb MD |
2926 | } |
2927 | ||
0f2d19dd | 2928 | |
434f2f7a DH |
2929 | /* scm_last_debug_frame contains a pointer to the last debugging information |
2930 | * stack frame. It is accessed very often from the debugging evaluator, so it | |
2931 | * should probably not be indirectly addressed. Better to save and restore it | |
2932 | * from the current root at any stack swaps. | |
6dbd0af5 MD |
2933 | */ |
2934 | ||
6dbd0af5 MD |
2935 | /* scm_debug_eframe_size is the number of slots available for pseudo |
2936 | * stack frames at each real stack frame. | |
2937 | */ | |
2938 | ||
c014a02e | 2939 | long scm_debug_eframe_size; |
6dbd0af5 | 2940 | |
434f2f7a DH |
2941 | int scm_debug_mode_p; |
2942 | int scm_check_entry_p; | |
2943 | int scm_check_apply_p; | |
2944 | int scm_check_exit_p; | |
72f19c26 | 2945 | int scm_check_memoize_p; |
6dbd0af5 | 2946 | |
c014a02e | 2947 | long scm_eval_stack; |
a74145b8 | 2948 | |
92c2555f | 2949 | scm_t_option scm_eval_opts[] = { |
62560650 HWN |
2950 | { SCM_OPTION_INTEGER, "stack", 22000, "Size of thread stacks (in machine words)." }, |
2951 | { 0 } | |
33b97402 MD |
2952 | }; |
2953 | ||
92c2555f | 2954 | scm_t_option scm_debug_opts[] = { |
b7ff98dd | 2955 | { SCM_OPTION_BOOLEAN, "cheap", 1, |
7c9c0169 | 2956 | "*This option is now obsolete. Setting it has no effect." }, |
b7ff98dd MD |
2957 | { SCM_OPTION_BOOLEAN, "breakpoints", 0, "*Check for breakpoints." }, |
2958 | { SCM_OPTION_BOOLEAN, "trace", 0, "*Trace mode." }, | |
2959 | { SCM_OPTION_BOOLEAN, "procnames", 1, | |
2960 | "Record procedure names at definition." }, | |
2961 | { SCM_OPTION_BOOLEAN, "backwards", 0, | |
2962 | "Display backtrace in anti-chronological order." }, | |
274dc5fd | 2963 | { SCM_OPTION_INTEGER, "width", 79, "Maximal width of backtrace." }, |
4e646a03 MD |
2964 | { SCM_OPTION_INTEGER, "indent", 10, "Maximal indentation in backtrace." }, |
2965 | { SCM_OPTION_INTEGER, "frames", 3, | |
b7ff98dd | 2966 | "Maximum number of tail-recursive frames in backtrace." }, |
4e646a03 MD |
2967 | { SCM_OPTION_INTEGER, "maxdepth", 1000, |
2968 | "Maximal number of stored backtrace frames." }, | |
2969 | { SCM_OPTION_INTEGER, "depth", 20, "Maximal length of printed backtrace." }, | |
11f77bfc MD |
2970 | { SCM_OPTION_BOOLEAN, "backtrace", 0, "Show backtrace on error." }, |
2971 | { SCM_OPTION_BOOLEAN, "debug", 0, "Use the debugging evaluator." }, | |
de3d1fc9 AW |
2972 | /* This default stack limit will be overridden by debug.c:init_stack_limit(), |
2973 | if we have getrlimit() and the stack limit is not INFINITY. But it is still | |
2974 | important, as some systems have both the soft and the hard limits set to | |
2975 | INFINITY; in that case we fall back to this value. | |
0ee05b85 | 2976 | |
de3d1fc9 AW |
2977 | The situation is aggravated by certain compilers, which can consume |
2978 | "beaucoup de stack", as they say in France. | |
2979 | ||
2980 | See http://thread.gmane.org/gmane.lisp.guile.devel/8599/focus=8662 for | |
2981 | more discussion. This setting is 640 KB on 32-bit arches (should be enough | |
2982 | for anyone!) or a whoppin' 1280 KB on 64-bit arches. | |
2983 | */ | |
2984 | { SCM_OPTION_INTEGER, "stack", 160000, "Stack size limit (measured in words; 0 = no check)." }, | |
243ebb61 HWN |
2985 | { SCM_OPTION_SCM, "show-file-name", (unsigned long)SCM_BOOL_T, |
2986 | "Show file names and line numbers " | |
2987 | "in backtraces when not `#f'. A value of `base' " | |
2988 | "displays only base names, while `#t' displays full names."}, | |
2989 | { SCM_OPTION_BOOLEAN, "warn-deprecated", 0, | |
2990 | "Warn when deprecated features are used." }, | |
62560650 | 2991 | { 0 }, |
6dbd0af5 MD |
2992 | }; |
2993 | ||
62560650 | 2994 | |
72f19c26 | 2995 | /* |
0ee05b85 HWN |
2996 | * this ordering is awkward and illogical, but we maintain it for |
2997 | * compatibility. --hwn | |
2998 | */ | |
92c2555f | 2999 | scm_t_option scm_evaluator_trap_table[] = { |
b6d75948 | 3000 | { SCM_OPTION_BOOLEAN, "traps", 0, "Enable evaluator traps." }, |
b7ff98dd MD |
3001 | { SCM_OPTION_BOOLEAN, "enter-frame", 0, "Trap when eval enters new frame." }, |
3002 | { SCM_OPTION_BOOLEAN, "apply-frame", 0, "Trap when entering apply." }, | |
d95c0b76 NJ |
3003 | { SCM_OPTION_BOOLEAN, "exit-frame", 0, "Trap when exiting eval or apply." }, |
3004 | { SCM_OPTION_SCM, "enter-frame-handler", (unsigned long)SCM_BOOL_F, "Handler for enter-frame traps." }, | |
3005 | { SCM_OPTION_SCM, "apply-frame-handler", (unsigned long)SCM_BOOL_F, "Handler for apply-frame traps." }, | |
62560650 | 3006 | { SCM_OPTION_SCM, "exit-frame-handler", (unsigned long)SCM_BOOL_F, "Handler for exit-frame traps." }, |
72f19c26 HWN |
3007 | { SCM_OPTION_BOOLEAN, "memoize-symbol", 0, "Trap when memoizing a symbol." }, |
3008 | { SCM_OPTION_SCM, "memoize-symbol-handler", (unsigned long)SCM_BOOL_F, "The handler for memoization." }, | |
62560650 | 3009 | { 0 } |
6dbd0af5 MD |
3010 | }; |
3011 | ||
72f19c26 | 3012 | |
a1ec6916 | 3013 | SCM_DEFINE (scm_eval_options_interface, "eval-options-interface", 0, 1, 0, |
1bbd0b84 | 3014 | (SCM setting), |
b3f26b14 MG |
3015 | "Option interface for the evaluation options. Instead of using\n" |
3016 | "this procedure directly, use the procedures @code{eval-enable},\n" | |
3939e9df | 3017 | "@code{eval-disable}, @code{eval-set!} and @code{eval-options}.") |
1bbd0b84 | 3018 | #define FUNC_NAME s_scm_eval_options_interface |
33b97402 MD |
3019 | { |
3020 | SCM ans; | |
876099d4 | 3021 | |
661ae7ab MV |
3022 | scm_dynwind_begin (0); |
3023 | scm_dynwind_critical_section (SCM_BOOL_F); | |
33b97402 MD |
3024 | ans = scm_options (setting, |
3025 | scm_eval_opts, | |
1bbd0b84 | 3026 | FUNC_NAME); |
a74145b8 | 3027 | scm_eval_stack = SCM_EVAL_STACK * sizeof (void *); |
661ae7ab | 3028 | scm_dynwind_end (); |
876099d4 | 3029 | |
33b97402 MD |
3030 | return ans; |
3031 | } | |
1bbd0b84 | 3032 | #undef FUNC_NAME |
33b97402 | 3033 | |
d0b07b5d | 3034 | |
a1ec6916 | 3035 | SCM_DEFINE (scm_evaluator_traps, "evaluator-traps-interface", 0, 1, 0, |
1bbd0b84 | 3036 | (SCM setting), |
b3f26b14 | 3037 | "Option interface for the evaluator trap options.") |
1bbd0b84 | 3038 | #define FUNC_NAME s_scm_evaluator_traps |
33b97402 MD |
3039 | { |
3040 | SCM ans; | |
72f19c26 HWN |
3041 | |
3042 | ||
3043 | scm_options_try (setting, | |
3044 | scm_evaluator_trap_table, | |
3045 | FUNC_NAME, 1); | |
9de87eea | 3046 | SCM_CRITICAL_SECTION_START; |
33b97402 MD |
3047 | ans = scm_options (setting, |
3048 | scm_evaluator_trap_table, | |
1bbd0b84 | 3049 | FUNC_NAME); |
72f19c26 | 3050 | |
2b0fb0a5 | 3051 | /* njrev: same again. */ |
33b97402 | 3052 | SCM_RESET_DEBUG_MODE; |
9de87eea | 3053 | SCM_CRITICAL_SECTION_END; |
33b97402 MD |
3054 | return ans; |
3055 | } | |
1bbd0b84 | 3056 | #undef FUNC_NAME |
33b97402 | 3057 | |
d0b07b5d | 3058 | |
0f2d19dd | 3059 | |
fdc28395 | 3060 | \f |
d0b07b5d | 3061 | |
fdc28395 KN |
3062 | /* Simple procedure calls |
3063 | */ | |
3064 | ||
3065 | SCM | |
3066 | scm_call_0 (SCM proc) | |
3067 | { | |
4abef68f AW |
3068 | if (SCM_PROGRAM_P (proc)) |
3069 | return scm_c_vm_run (scm_the_vm (), proc, NULL, 0); | |
3070 | else | |
3071 | return scm_apply (proc, SCM_EOL, SCM_EOL); | |
fdc28395 KN |
3072 | } |
3073 | ||
3074 | SCM | |
3075 | scm_call_1 (SCM proc, SCM arg1) | |
3076 | { | |
4abef68f AW |
3077 | if (SCM_PROGRAM_P (proc)) |
3078 | return scm_c_vm_run (scm_the_vm (), proc, &arg1, 1); | |
3079 | else | |
3080 | return scm_apply (proc, arg1, scm_listofnull); | |
fdc28395 KN |
3081 | } |
3082 | ||
3083 | SCM | |
3084 | scm_call_2 (SCM proc, SCM arg1, SCM arg2) | |
3085 | { | |
4abef68f AW |
3086 | if (SCM_PROGRAM_P (proc)) |
3087 | { | |
3088 | SCM args[] = { arg1, arg2 }; | |
3089 | return scm_c_vm_run (scm_the_vm (), proc, args, 2); | |
3090 | } | |
3091 | else | |
3092 | return scm_apply (proc, arg1, scm_cons (arg2, scm_listofnull)); | |
fdc28395 KN |
3093 | } |
3094 | ||
3095 | SCM | |
3096 | scm_call_3 (SCM proc, SCM arg1, SCM arg2, SCM arg3) | |
3097 | { | |
4abef68f AW |
3098 | if (SCM_PROGRAM_P (proc)) |
3099 | { | |
3100 | SCM args[] = { arg1, arg2, arg3 }; | |
3101 | return scm_c_vm_run (scm_the_vm (), proc, args, 3); | |
3102 | } | |
3103 | else | |
3104 | return scm_apply (proc, arg1, scm_cons2 (arg2, arg3, scm_listofnull)); | |
fdc28395 KN |
3105 | } |
3106 | ||
d95c0b76 NJ |
3107 | SCM |
3108 | scm_call_4 (SCM proc, SCM arg1, SCM arg2, SCM arg3, SCM arg4) | |
3109 | { | |
4abef68f AW |
3110 | if (SCM_PROGRAM_P (proc)) |
3111 | { | |
3112 | SCM args[] = { arg1, arg2, arg3, arg4 }; | |
3113 | return scm_c_vm_run (scm_the_vm (), proc, args, 4); | |
3114 | } | |
3115 | else | |
3116 | return scm_apply (proc, arg1, scm_cons2 (arg2, arg3, | |
3117 | scm_cons (arg4, scm_listofnull))); | |
d95c0b76 NJ |
3118 | } |
3119 | ||
fdc28395 KN |
3120 | /* Simple procedure applies |
3121 | */ | |
3122 | ||
3123 | SCM | |
3124 | scm_apply_0 (SCM proc, SCM args) | |
3125 | { | |
3126 | return scm_apply (proc, args, SCM_EOL); | |
3127 | } | |
3128 | ||
3129 | SCM | |
3130 | scm_apply_1 (SCM proc, SCM arg1, SCM args) | |
3131 | { | |
3132 | return scm_apply (proc, scm_cons (arg1, args), SCM_EOL); | |
3133 | } | |
3134 | ||
3135 | SCM | |
3136 | scm_apply_2 (SCM proc, SCM arg1, SCM arg2, SCM args) | |
3137 | { | |
3138 | return scm_apply (proc, scm_cons2 (arg1, arg2, args), SCM_EOL); | |
3139 | } | |
3140 | ||
3141 | SCM | |
3142 | scm_apply_3 (SCM proc, SCM arg1, SCM arg2, SCM arg3, SCM args) | |
3143 | { | |
3144 | return scm_apply (proc, scm_cons (arg1, scm_cons2 (arg2, arg3, args)), | |
3145 | SCM_EOL); | |
3146 | } | |
3147 | ||
82a2622a | 3148 | /* This code processes the arguments to apply: |
b145c172 JB |
3149 | |
3150 | (apply PROC ARG1 ... ARGS) | |
3151 | ||
82a2622a JB |
3152 | Given a list (ARG1 ... ARGS), this function conses the ARG1 |
3153 | ... arguments onto the front of ARGS, and returns the resulting | |
3154 | list. Note that ARGS is a list; thus, the argument to this | |
3155 | function is a list whose last element is a list. | |
3156 | ||
3157 | Apply calls this function, and applies PROC to the elements of the | |
b145c172 JB |
3158 | result. apply:nconc2last takes care of building the list of |
3159 | arguments, given (ARG1 ... ARGS). | |
3160 | ||
82a2622a JB |
3161 | Rather than do new consing, apply:nconc2last destroys its argument. |
3162 | On that topic, this code came into my care with the following | |
3163 | beautifully cryptic comment on that topic: "This will only screw | |
3164 | you if you do (scm_apply scm_apply '( ... ))" If you know what | |
3165 | they're referring to, send me a patch to this comment. */ | |
b145c172 | 3166 | |
3b3b36dd | 3167 | SCM_DEFINE (scm_nconc2last, "apply:nconc2last", 1, 0, 0, |
b3f26b14 MG |
3168 | (SCM lst), |
3169 | "Given a list (@var{arg1} @dots{} @var{args}), this function\n" | |
3170 | "conses the @var{arg1} @dots{} arguments onto the front of\n" | |
3171 | "@var{args}, and returns the resulting list. Note that\n" | |
3172 | "@var{args} is a list; thus, the argument to this function is\n" | |
3173 | "a list whose last element is a list.\n" | |
3174 | "Note: Rather than do new consing, @code{apply:nconc2last}\n" | |
3175 | "destroys its argument, so use with care.") | |
1bbd0b84 | 3176 | #define FUNC_NAME s_scm_nconc2last |
0f2d19dd JB |
3177 | { |
3178 | SCM *lloc; | |
34d19ef6 | 3179 | SCM_VALIDATE_NONEMPTYLIST (1, lst); |
0f2d19dd | 3180 | lloc = &lst; |
a61f4e0c | 3181 | while (!scm_is_null (SCM_CDR (*lloc))) /* Perhaps should be |
c96d76b8 NJ |
3182 | SCM_NULL_OR_NIL_P, but not |
3183 | needed in 99.99% of cases, | |
3184 | and it could seriously hurt | |
3185 | performance. - Neil */ | |
a23afe53 | 3186 | lloc = SCM_CDRLOC (*lloc); |
1bbd0b84 | 3187 | SCM_ASSERT (scm_ilength (SCM_CAR (*lloc)) >= 0, lst, SCM_ARG1, FUNC_NAME); |
0f2d19dd JB |
3188 | *lloc = SCM_CAR (*lloc); |
3189 | return lst; | |
3190 | } | |
1bbd0b84 | 3191 | #undef FUNC_NAME |
0f2d19dd | 3192 | |
0f2d19dd | 3193 | |
6dbd0af5 MD |
3194 | |
3195 | /* SECTION: The rest of this file is only read once. | |
3196 | */ | |
3197 | ||
504d99c5 MD |
3198 | /* Trampolines |
3199 | * | |
3200 | * Trampolines make it possible to move procedure application dispatch | |
3201 | * outside inner loops. The motivation was clean implementation of | |
3202 | * efficient replacements of R5RS primitives in SRFI-1. | |
3203 | * | |
3204 | * The semantics is clear: scm_trampoline_N returns an optimized | |
3205 | * version of scm_call_N (or NULL if the procedure isn't applicable | |
3206 | * on N args). | |
3207 | * | |
3208 | * Applying the optimization to map and for-each increased efficiency | |
3209 | * noticeably. For example, (map abs ls) is now 8 times faster than | |
3210 | * before. | |
3211 | */ | |
3212 | ||
756414cf MD |
3213 | static SCM |
3214 | call_subr0_0 (SCM proc) | |
3215 | { | |
3216 | return SCM_SUBRF (proc) (); | |
3217 | } | |
3218 | ||
3219 | static SCM | |
3220 | call_subr1o_0 (SCM proc) | |
3221 | { | |
3222 | return SCM_SUBRF (proc) (SCM_UNDEFINED); | |
3223 | } | |
3224 | ||
3225 | static SCM | |
3226 | call_lsubr_0 (SCM proc) | |
3227 | { | |
3228 | return SCM_SUBRF (proc) (SCM_EOL); | |
3229 | } | |
3230 | ||
3231 | SCM | |
3232 | scm_i_call_closure_0 (SCM proc) | |
3233 | { | |
6a3f13f0 DH |
3234 | const SCM env = SCM_EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), |
3235 | SCM_EOL, | |
3236 | SCM_ENV (proc)); | |
3237 | const SCM result = scm_eval_body (SCM_CLOSURE_BODY (proc), env); | |
d0b07b5d | 3238 | return result; |
756414cf MD |
3239 | } |
3240 | ||
3241 | scm_t_trampoline_0 | |
3242 | scm_trampoline_0 (SCM proc) | |
3243 | { | |
2510c810 DH |
3244 | scm_t_trampoline_0 trampoline; |
3245 | ||
756414cf | 3246 | if (SCM_IMP (proc)) |
d0b07b5d | 3247 | return NULL; |
2510c810 | 3248 | |
756414cf MD |
3249 | switch (SCM_TYP7 (proc)) |
3250 | { | |
3251 | case scm_tc7_subr_0: | |
2510c810 DH |
3252 | trampoline = call_subr0_0; |
3253 | break; | |
756414cf | 3254 | case scm_tc7_subr_1o: |
2510c810 DH |
3255 | trampoline = call_subr1o_0; |
3256 | break; | |
756414cf | 3257 | case scm_tc7_lsubr: |
2510c810 DH |
3258 | trampoline = call_lsubr_0; |
3259 | break; | |
756414cf MD |
3260 | case scm_tcs_closures: |
3261 | { | |
3262 | SCM formals = SCM_CLOSURE_FORMALS (proc); | |
a61f4e0c | 3263 | if (scm_is_null (formals) || !scm_is_pair (formals)) |
2510c810 | 3264 | trampoline = scm_i_call_closure_0; |
756414cf | 3265 | else |
d0b07b5d | 3266 | return NULL; |
2510c810 | 3267 | break; |
756414cf MD |
3268 | } |
3269 | case scm_tcs_struct: | |
3270 | if (SCM_OBJ_CLASS_FLAGS (proc) & SCM_CLASSF_PURE_GENERIC) | |
2510c810 | 3271 | trampoline = scm_call_generic_0; |
2510c810 DH |
3272 | else |
3273 | return NULL; | |
3274 | break; | |
756414cf MD |
3275 | case scm_tc7_smob: |
3276 | if (SCM_SMOB_APPLICABLE_P (proc)) | |
2510c810 | 3277 | trampoline = SCM_SMOB_DESCRIPTOR (proc).apply_0; |
756414cf | 3278 | else |
d0b07b5d | 3279 | return NULL; |
2510c810 | 3280 | break; |
756414cf MD |
3281 | case scm_tc7_asubr: |
3282 | case scm_tc7_rpsubr: | |
e20d7001 | 3283 | case scm_tc7_gsubr: |
756414cf | 3284 | case scm_tc7_pws: |
2fb924f6 | 3285 | case scm_tc7_program: |
2510c810 DH |
3286 | trampoline = scm_call_0; |
3287 | break; | |
756414cf | 3288 | default: |
2510c810 | 3289 | return NULL; /* not applicable on zero arguments */ |
756414cf | 3290 | } |
2510c810 DH |
3291 | /* We only reach this point if a valid trampoline was determined. */ |
3292 | ||
3293 | /* If debugging is enabled, we want to see all calls to proc on the stack. | |
3294 | * Thus, we replace the trampoline shortcut with scm_call_0. */ | |
434f2f7a | 3295 | if (scm_debug_mode_p) |
2510c810 DH |
3296 | return scm_call_0; |
3297 | else | |
3298 | return trampoline; | |
756414cf MD |
3299 | } |
3300 | ||
504d99c5 MD |
3301 | static SCM |
3302 | call_subr1_1 (SCM proc, SCM arg1) | |
3303 | { | |
3304 | return SCM_SUBRF (proc) (arg1); | |
3305 | } | |
3306 | ||
9ed24633 MD |
3307 | static SCM |
3308 | call_subr2o_1 (SCM proc, SCM arg1) | |
3309 | { | |
3310 | return SCM_SUBRF (proc) (arg1, SCM_UNDEFINED); | |
3311 | } | |
3312 | ||
504d99c5 MD |
3313 | static SCM |
3314 | call_lsubr_1 (SCM proc, SCM arg1) | |
3315 | { | |
3316 | return SCM_SUBRF (proc) (scm_list_1 (arg1)); | |
3317 | } | |
3318 | ||
3319 | static SCM | |
3320 | call_dsubr_1 (SCM proc, SCM arg1) | |
3321 | { | |
e11e83f3 | 3322 | if (SCM_I_INUMP (arg1)) |
504d99c5 | 3323 | { |
0ee05b85 | 3324 | return (scm_from_double (SCM_DSUBRF (proc) ((double) SCM_I_INUM (arg1)))); |
504d99c5 MD |
3325 | } |
3326 | else if (SCM_REALP (arg1)) | |
3327 | { | |
0ee05b85 | 3328 | return (scm_from_double (SCM_DSUBRF (proc) (SCM_REAL_VALUE (arg1)))); |
504d99c5 | 3329 | } |
504d99c5 | 3330 | else if (SCM_BIGP (arg1)) |
f92e85f7 | 3331 | { |
0ee05b85 | 3332 | return (scm_from_double (SCM_DSUBRF (proc) (scm_i_big2dbl (arg1)))); |
f92e85f7 MV |
3333 | } |
3334 | else if (SCM_FRACTIONP (arg1)) | |
3335 | { | |
0ee05b85 | 3336 | return (scm_from_double (SCM_DSUBRF (proc) (scm_i_fraction2double (arg1)))); |
f92e85f7 | 3337 | } |
0193377d | 3338 | SCM_WTA_DISPATCH_1_SUBR (proc, arg1, SCM_ARG1); |
504d99c5 MD |
3339 | } |
3340 | ||
3341 | static SCM | |
3342 | call_cxr_1 (SCM proc, SCM arg1) | |
3343 | { | |
a61f4e0c | 3344 | return scm_i_chase_pairs (arg1, (scm_t_bits) SCM_SUBRF (proc)); |
504d99c5 MD |
3345 | } |
3346 | ||
3347 | static SCM | |
3348 | call_closure_1 (SCM proc, SCM arg1) | |
3349 | { | |
6a3f13f0 DH |
3350 | const SCM env = SCM_EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), |
3351 | scm_list_1 (arg1), | |
3352 | SCM_ENV (proc)); | |
3353 | const SCM result = scm_eval_body (SCM_CLOSURE_BODY (proc), env); | |
d0b07b5d | 3354 | return result; |
504d99c5 MD |
3355 | } |
3356 | ||
3357 | scm_t_trampoline_1 | |
3358 | scm_trampoline_1 (SCM proc) | |
3359 | { | |
2510c810 DH |
3360 | scm_t_trampoline_1 trampoline; |
3361 | ||
504d99c5 | 3362 | if (SCM_IMP (proc)) |
d0b07b5d | 3363 | return NULL; |
2510c810 | 3364 | |
504d99c5 MD |
3365 | switch (SCM_TYP7 (proc)) |
3366 | { | |
3367 | case scm_tc7_subr_1: | |
3368 | case scm_tc7_subr_1o: | |
2510c810 DH |
3369 | trampoline = call_subr1_1; |
3370 | break; | |
9ed24633 | 3371 | case scm_tc7_subr_2o: |
2510c810 DH |
3372 | trampoline = call_subr2o_1; |
3373 | break; | |
504d99c5 | 3374 | case scm_tc7_lsubr: |
2510c810 DH |
3375 | trampoline = call_lsubr_1; |
3376 | break; | |
14b18ed6 | 3377 | case scm_tc7_dsubr: |
2510c810 DH |
3378 | trampoline = call_dsubr_1; |
3379 | break; | |
504d99c5 | 3380 | case scm_tc7_cxr: |
2510c810 DH |
3381 | trampoline = call_cxr_1; |
3382 | break; | |
504d99c5 MD |
3383 | case scm_tcs_closures: |
3384 | { | |
3385 | SCM formals = SCM_CLOSURE_FORMALS (proc); | |
a61f4e0c MV |
3386 | if (!scm_is_null (formals) |
3387 | && (!scm_is_pair (formals) || !scm_is_pair (SCM_CDR (formals)))) | |
2510c810 | 3388 | trampoline = call_closure_1; |
504d99c5 | 3389 | else |
d0b07b5d | 3390 | return NULL; |
2510c810 | 3391 | break; |
504d99c5 MD |
3392 | } |
3393 | case scm_tcs_struct: | |
3394 | if (SCM_OBJ_CLASS_FLAGS (proc) & SCM_CLASSF_PURE_GENERIC) | |
2510c810 | 3395 | trampoline = scm_call_generic_1; |
2510c810 DH |
3396 | else |
3397 | return NULL; | |
3398 | break; | |
504d99c5 MD |
3399 | case scm_tc7_smob: |
3400 | if (SCM_SMOB_APPLICABLE_P (proc)) | |
2510c810 | 3401 | trampoline = SCM_SMOB_DESCRIPTOR (proc).apply_1; |
504d99c5 | 3402 | else |
d0b07b5d | 3403 | return NULL; |
2510c810 | 3404 | break; |
504d99c5 MD |
3405 | case scm_tc7_asubr: |
3406 | case scm_tc7_rpsubr: | |
e20d7001 | 3407 | case scm_tc7_gsubr: |
504d99c5 | 3408 | case scm_tc7_pws: |
2fb924f6 | 3409 | case scm_tc7_program: |
2510c810 DH |
3410 | trampoline = scm_call_1; |
3411 | break; | |
504d99c5 | 3412 | default: |
d0b07b5d | 3413 | return NULL; /* not applicable on one arg */ |
504d99c5 | 3414 | } |
2510c810 DH |
3415 | /* We only reach this point if a valid trampoline was determined. */ |
3416 | ||
3417 | /* If debugging is enabled, we want to see all calls to proc on the stack. | |
3418 | * Thus, we replace the trampoline shortcut with scm_call_1. */ | |
434f2f7a | 3419 | if (scm_debug_mode_p) |
2510c810 DH |
3420 | return scm_call_1; |
3421 | else | |
3422 | return trampoline; | |
504d99c5 MD |
3423 | } |
3424 | ||
3425 | static SCM | |
3426 | call_subr2_2 (SCM proc, SCM arg1, SCM arg2) | |
3427 | { | |
3428 | return SCM_SUBRF (proc) (arg1, arg2); | |
3429 | } | |
3430 | ||
9ed24633 MD |
3431 | static SCM |
3432 | call_lsubr2_2 (SCM proc, SCM arg1, SCM arg2) | |
3433 | { | |
3434 | return SCM_SUBRF (proc) (arg1, arg2, SCM_EOL); | |
3435 | } | |
3436 | ||
504d99c5 MD |
3437 | static SCM |
3438 | call_lsubr_2 (SCM proc, SCM arg1, SCM arg2) | |
3439 | { | |
3440 | return SCM_SUBRF (proc) (scm_list_2 (arg1, arg2)); | |
3441 | } | |
3442 | ||
3443 | static SCM | |
3444 | call_closure_2 (SCM proc, SCM arg1, SCM arg2) | |
3445 | { | |
6a3f13f0 DH |
3446 | const SCM env = SCM_EXTEND_ENV (SCM_CLOSURE_FORMALS (proc), |
3447 | scm_list_2 (arg1, arg2), | |
3448 | SCM_ENV (proc)); | |
3449 | const SCM result = scm_eval_body (SCM_CLOSURE_BODY (proc), env); | |
d0b07b5d | 3450 | return result; |
504d99c5 MD |
3451 | } |
3452 | ||
3453 | scm_t_trampoline_2 | |
3454 | scm_trampoline_2 (SCM proc) | |
3455 | { | |
2510c810 DH |
3456 | scm_t_trampoline_2 trampoline; |
3457 | ||
504d99c5 | 3458 | if (SCM_IMP (proc)) |
d0b07b5d | 3459 | return NULL; |
2510c810 | 3460 | |
504d99c5 MD |
3461 | switch (SCM_TYP7 (proc)) |
3462 | { | |
3463 | case scm_tc7_subr_2: | |
3464 | case scm_tc7_subr_2o: | |
3465 | case scm_tc7_rpsubr: | |
3466 | case scm_tc7_asubr: | |
2510c810 DH |
3467 | trampoline = call_subr2_2; |
3468 | break; | |
9ed24633 | 3469 | case scm_tc7_lsubr_2: |
2510c810 DH |
3470 | trampoline = call_lsubr2_2; |
3471 | break; | |
504d99c5 | 3472 | case scm_tc7_lsubr: |
2510c810 DH |
3473 | trampoline = call_lsubr_2; |
3474 | break; | |
504d99c5 MD |
3475 | case scm_tcs_closures: |
3476 | { | |
3477 | SCM formals = SCM_CLOSURE_FORMALS (proc); | |
a61f4e0c MV |
3478 | if (!scm_is_null (formals) |
3479 | && (!scm_is_pair (formals) | |
3480 | || (!scm_is_null (SCM_CDR (formals)) | |
3481 | && (!scm_is_pair (SCM_CDR (formals)) | |
3482 | || !scm_is_pair (SCM_CDDR (formals)))))) | |
2510c810 | 3483 | trampoline = call_closure_2; |
504d99c5 | 3484 | else |
d0b07b5d | 3485 | return NULL; |
2510c810 | 3486 | break; |
504d99c5 MD |
3487 | } |
3488 | case scm_tcs_struct: | |
3489 | if (SCM_OBJ_CLASS_FLAGS (proc) & SCM_CLASSF_PURE_GENERIC) | |
2510c810 | 3490 | trampoline = scm_call_generic_2; |
2510c810 DH |
3491 | else |
3492 | return NULL; | |
3493 | break; | |
504d99c5 MD |
3494 | case scm_tc7_smob: |
3495 | if (SCM_SMOB_APPLICABLE_P (proc)) | |
2510c810 | 3496 | trampoline = SCM_SMOB_DESCRIPTOR (proc).apply_2; |
504d99c5 | 3497 | else |
d0b07b5d | 3498 | return NULL; |
2510c810 | 3499 | break; |
e20d7001 | 3500 | case scm_tc7_gsubr: |
504d99c5 | 3501 | case scm_tc7_pws: |
2fb924f6 | 3502 | case scm_tc7_program: |
2510c810 DH |
3503 | trampoline = scm_call_2; |
3504 | break; | |
504d99c5 | 3505 | default: |
d0b07b5d | 3506 | return NULL; /* not applicable on two args */ |
504d99c5 | 3507 | } |
2510c810 DH |
3508 | /* We only reach this point if a valid trampoline was determined. */ |
3509 | ||
3510 | /* If debugging is enabled, we want to see all calls to proc on the stack. | |
3511 | * Thus, we replace the trampoline shortcut with scm_call_2. */ | |
434f2f7a | 3512 | if (scm_debug_mode_p) |
2510c810 DH |
3513 | return scm_call_2; |
3514 | else | |
3515 | return trampoline; | |
504d99c5 MD |
3516 | } |
3517 | ||
d9c393f5 JB |
3518 | /* Typechecking for multi-argument MAP and FOR-EACH. |
3519 | ||
47c3f06d | 3520 | Verify that each element of the vector ARGV, except for the first, |
d9c393f5 | 3521 | is a proper list whose length is LEN. Attribute errors to WHO, |
47c3f06d | 3522 | and claim that the i'th element of ARGV is WHO's i+2'th argument. */ |
d9c393f5 | 3523 | static inline void |
47c3f06d | 3524 | check_map_args (SCM argv, |
c014a02e | 3525 | long len, |
47c3f06d MD |
3526 | SCM gf, |
3527 | SCM proc, | |
3528 | SCM args, | |
3529 | const char *who) | |
d9c393f5 | 3530 | { |
c014a02e | 3531 | long i; |
d9c393f5 | 3532 | |
4057a3e0 | 3533 | for (i = SCM_SIMPLE_VECTOR_LENGTH (argv) - 1; i >= 1; i--) |
d9c393f5 | 3534 | { |
4057a3e0 MV |
3535 | SCM elt = SCM_SIMPLE_VECTOR_REF (argv, i); |
3536 | long elt_len = scm_ilength (elt); | |
d9c393f5 JB |
3537 | |
3538 | if (elt_len < 0) | |
47c3f06d MD |
3539 | { |
3540 | if (gf) | |
3541 | scm_apply_generic (gf, scm_cons (proc, args)); | |
3542 | else | |
4057a3e0 | 3543 | scm_wrong_type_arg (who, i + 2, elt); |
47c3f06d | 3544 | } |
d9c393f5 JB |
3545 | |
3546 | if (elt_len != len) | |
4057a3e0 | 3547 | scm_out_of_range_pos (who, elt, scm_from_long (i + 2)); |
d9c393f5 | 3548 | } |
d9c393f5 JB |
3549 | } |
3550 | ||
3551 | ||
47c3f06d | 3552 | SCM_GPROC (s_map, "map", 2, 0, 1, scm_map, g_map); |
1cc91f1b | 3553 | |
368bf056 MD |
3554 | /* Note: Currently, scm_map applies PROC to the argument list(s) |
3555 | sequentially, starting with the first element(s). This is used in | |
8878f040 | 3556 | evalext.c where the Scheme procedure `map-in-order', which guarantees |
368bf056 | 3557 | sequential behaviour, is implemented using scm_map. If the |
8878f040 | 3558 | behaviour changes, we need to update `map-in-order'. |
368bf056 MD |
3559 | */ |
3560 | ||
0f2d19dd | 3561 | SCM |
1bbd0b84 | 3562 | scm_map (SCM proc, SCM arg1, SCM args) |
af45e3b0 | 3563 | #define FUNC_NAME s_map |
0f2d19dd | 3564 | { |
c014a02e | 3565 | long i, len; |
0f2d19dd JB |
3566 | SCM res = SCM_EOL; |
3567 | SCM *pres = &res; | |
0f2d19dd | 3568 | |
d9c393f5 | 3569 | len = scm_ilength (arg1); |
47c3f06d MD |
3570 | SCM_GASSERTn (len >= 0, |
3571 | g_map, scm_cons2 (proc, arg1, args), SCM_ARG2, s_map); | |
af45e3b0 | 3572 | SCM_VALIDATE_REST_ARGUMENT (args); |
a61f4e0c | 3573 | if (scm_is_null (args)) |
0f2d19dd | 3574 | { |
504d99c5 MD |
3575 | scm_t_trampoline_1 call = scm_trampoline_1 (proc); |
3576 | SCM_GASSERT2 (call, g_map, proc, arg1, SCM_ARG1, s_map); | |
3577 | while (SCM_NIMP (arg1)) | |
3578 | { | |
3579 | *pres = scm_list_1 (call (proc, SCM_CAR (arg1))); | |
3580 | pres = SCM_CDRLOC (*pres); | |
3581 | arg1 = SCM_CDR (arg1); | |
3582 | } | |
3583 | return res; | |
3584 | } | |
a61f4e0c | 3585 | if (scm_is_null (SCM_CDR (args))) |
504d99c5 MD |
3586 | { |
3587 | SCM arg2 = SCM_CAR (args); | |
3588 | int len2 = scm_ilength (arg2); | |
3589 | scm_t_trampoline_2 call = scm_trampoline_2 (proc); | |
3590 | SCM_GASSERTn (call, | |
3591 | g_map, scm_cons2 (proc, arg1, args), SCM_ARG1, s_map); | |
3592 | SCM_GASSERTn (len2 >= 0, | |
3593 | g_map, scm_cons2 (proc, arg1, args), SCM_ARG3, s_map); | |
3594 | if (len2 != len) | |
3595 | SCM_OUT_OF_RANGE (3, arg2); | |
0f2d19dd JB |
3596 | while (SCM_NIMP (arg1)) |
3597 | { | |
504d99c5 | 3598 | *pres = scm_list_1 (call (proc, SCM_CAR (arg1), SCM_CAR (arg2))); |
a23afe53 | 3599 | pres = SCM_CDRLOC (*pres); |
0f2d19dd | 3600 | arg1 = SCM_CDR (arg1); |
504d99c5 | 3601 | arg2 = SCM_CDR (arg2); |
0f2d19dd JB |
3602 | } |
3603 | return res; | |
3604 | } | |
05b15362 DH |
3605 | arg1 = scm_cons (arg1, args); |
3606 | args = scm_vector (arg1); | |
47c3f06d | 3607 | check_map_args (args, len, g_map, proc, arg1, s_map); |
0f2d19dd JB |
3608 | while (1) |
3609 | { | |
3610 | arg1 = SCM_EOL; | |
4057a3e0 | 3611 | for (i = SCM_SIMPLE_VECTOR_LENGTH (args) - 1; i >= 0; i--) |
0f2d19dd | 3612 | { |
4057a3e0 MV |
3613 | SCM elt = SCM_SIMPLE_VECTOR_REF (args, i); |
3614 | if (SCM_IMP (elt)) | |
d9c393f5 | 3615 | return res; |
4057a3e0 MV |
3616 | arg1 = scm_cons (SCM_CAR (elt), arg1); |
3617 | SCM_SIMPLE_VECTOR_SET (args, i, SCM_CDR (elt)); | |
0f2d19dd | 3618 | } |
8ea46249 | 3619 | *pres = scm_list_1 (scm_apply (proc, arg1, SCM_EOL)); |
a23afe53 | 3620 | pres = SCM_CDRLOC (*pres); |
0f2d19dd JB |
3621 | } |
3622 | } | |
af45e3b0 | 3623 | #undef FUNC_NAME |
0f2d19dd JB |
3624 | |
3625 | ||
47c3f06d | 3626 | SCM_GPROC (s_for_each, "for-each", 2, 0, 1, scm_for_each, g_for_each); |
1cc91f1b | 3627 | |
0f2d19dd | 3628 | SCM |
1bbd0b84 | 3629 | scm_for_each (SCM proc, SCM arg1, SCM args) |
af45e3b0 | 3630 | #define FUNC_NAME s_for_each |
0f2d19dd | 3631 | { |
c014a02e | 3632 | long i, len; |
d9c393f5 | 3633 | len = scm_ilength (arg1); |
47c3f06d MD |
3634 | SCM_GASSERTn (len >= 0, g_for_each, scm_cons2 (proc, arg1, args), |
3635 | SCM_ARG2, s_for_each); | |
af45e3b0 | 3636 | SCM_VALIDATE_REST_ARGUMENT (args); |
a61f4e0c | 3637 | if (scm_is_null (args)) |
0f2d19dd | 3638 | { |
504d99c5 MD |
3639 | scm_t_trampoline_1 call = scm_trampoline_1 (proc); |
3640 | SCM_GASSERT2 (call, g_for_each, proc, arg1, SCM_ARG1, s_for_each); | |
3641 | while (SCM_NIMP (arg1)) | |
3642 | { | |
3643 | call (proc, SCM_CAR (arg1)); | |
3644 | arg1 = SCM_CDR (arg1); | |
3645 | } | |
3646 | return SCM_UNSPECIFIED; | |
3647 | } | |
a61f4e0c | 3648 | if (scm_is_null (SCM_CDR (args))) |
504d99c5 MD |
3649 | { |
3650 | SCM arg2 = SCM_CAR (args); | |
3651 | int len2 = scm_ilength (arg2); | |
3652 | scm_t_trampoline_2 call = scm_trampoline_2 (proc); | |
3653 | SCM_GASSERTn (call, g_for_each, | |
3654 | scm_cons2 (proc, arg1, args), SCM_ARG1, s_for_each); | |
3655 | SCM_GASSERTn (len2 >= 0, g_for_each, | |
3656 | scm_cons2 (proc, arg1, args), SCM_ARG3, s_for_each); | |
3657 | if (len2 != len) | |
3658 | SCM_OUT_OF_RANGE (3, arg2); | |
c96d76b8 | 3659 | while (SCM_NIMP (arg1)) |
0f2d19dd | 3660 | { |
504d99c5 | 3661 | call (proc, SCM_CAR (arg1), SCM_CAR (arg2)); |
0f2d19dd | 3662 | arg1 = SCM_CDR (arg1); |
504d99c5 | 3663 | arg2 = SCM_CDR (arg2); |
0f2d19dd JB |
3664 | } |
3665 | return SCM_UNSPECIFIED; | |
3666 | } | |
05b15362 DH |
3667 | arg1 = scm_cons (arg1, args); |
3668 | args = scm_vector (arg1); | |
47c3f06d | 3669 | check_map_args (args, len, g_for_each, proc, arg1, s_for_each); |
0f2d19dd JB |
3670 | while (1) |
3671 | { | |
3672 | arg1 = SCM_EOL; | |
4057a3e0 | 3673 | for (i = SCM_SIMPLE_VECTOR_LENGTH (args) - 1; i >= 0; i--) |
0f2d19dd | 3674 | { |
4057a3e0 MV |
3675 | SCM elt = SCM_SIMPLE_VECTOR_REF (args, i); |
3676 | if (SCM_IMP (elt)) | |
c96d76b8 | 3677 | return SCM_UNSPECIFIED; |
4057a3e0 MV |
3678 | arg1 = scm_cons (SCM_CAR (elt), arg1); |
3679 | SCM_SIMPLE_VECTOR_SET (args, i, SCM_CDR (elt)); | |
0f2d19dd JB |
3680 | } |
3681 | scm_apply (proc, arg1, SCM_EOL); | |
3682 | } | |
3683 | } | |
af45e3b0 | 3684 | #undef FUNC_NAME |
0f2d19dd | 3685 | |
1cc91f1b | 3686 | |
0f2d19dd | 3687 | SCM |
6e8d25a6 | 3688 | scm_closure (SCM code, SCM env) |
0f2d19dd | 3689 | { |
16d4699b MV |
3690 | SCM z; |
3691 | SCM closcar = scm_cons (code, SCM_EOL); | |
3db825b0 LC |
3692 | z = scm_immutable_cell (SCM_UNPACK (closcar) + scm_tc3_closure, |
3693 | (scm_t_bits) env); | |
16d4699b | 3694 | scm_remember_upto_here (closcar); |
0f2d19dd JB |
3695 | return z; |
3696 | } | |
3697 | ||
3698 | ||
92c2555f | 3699 | scm_t_bits scm_tc16_promise; |
1cc91f1b | 3700 | |
7c455996 AW |
3701 | SCM_DEFINE (scm_make_promise, "make-promise", 1, 0, 0, |
3702 | (SCM thunk), | |
3703 | "Create a new promise object.\n\n" | |
3704 | "@code{make-promise} is a procedural form of @code{delay}.\n" | |
3705 | "These two expressions are equivalent:\n" | |
3706 | "@lisp\n" | |
3707 | "(delay @var{exp})\n" | |
3708 | "(make-promise (lambda () @var{exp}))\n" | |
3709 | "@end lisp\n") | |
3710 | #define FUNC_NAME s_scm_make_promise | |
3711 | { | |
3712 | SCM_VALIDATE_THUNK (1, thunk); | |
28d52ebb | 3713 | SCM_RETURN_NEWSMOB2 (scm_tc16_promise, |
7c455996 | 3714 | SCM_UNPACK (thunk), |
9de87eea MV |
3715 | scm_make_recursive_mutex ()); |
3716 | } | |
7c455996 | 3717 | #undef FUNC_NAME |
9de87eea | 3718 | |
1cc91f1b | 3719 | |
0f2d19dd | 3720 | static int |
e841c3e0 | 3721 | promise_print (SCM exp, SCM port, scm_print_state *pstate) |
0f2d19dd | 3722 | { |
19402679 | 3723 | int writingp = SCM_WRITINGP (pstate); |
b7f3516f | 3724 | scm_puts ("#<promise ", port); |
19402679 | 3725 | SCM_SET_WRITINGP (pstate, 1); |
28d52ebb | 3726 | scm_iprin1 (SCM_PROMISE_DATA (exp), port, pstate); |
19402679 | 3727 | SCM_SET_WRITINGP (pstate, writingp); |
b7f3516f | 3728 | scm_putc ('>', port); |
0f2d19dd JB |
3729 | return !0; |
3730 | } | |
3731 | ||
3b3b36dd | 3732 | SCM_DEFINE (scm_force, "force", 1, 0, 0, |
28d52ebb | 3733 | (SCM promise), |
67e8151b MG |
3734 | "If the promise @var{x} has not been computed yet, compute and\n" |
3735 | "return @var{x}, otherwise just return the previously computed\n" | |
3736 | "value.") | |
1bbd0b84 | 3737 | #define FUNC_NAME s_scm_force |
0f2d19dd | 3738 | { |
28d52ebb | 3739 | SCM_VALIDATE_SMOB (1, promise, promise); |
9de87eea | 3740 | scm_lock_mutex (SCM_PROMISE_MUTEX (promise)); |
28d52ebb | 3741 | if (!SCM_PROMISE_COMPUTED_P (promise)) |
0f2d19dd | 3742 | { |
28d52ebb MD |
3743 | SCM ans = scm_call_0 (SCM_PROMISE_DATA (promise)); |
3744 | if (!SCM_PROMISE_COMPUTED_P (promise)) | |
0f2d19dd | 3745 | { |
28d52ebb MD |
3746 | SCM_SET_PROMISE_DATA (promise, ans); |
3747 | SCM_SET_PROMISE_COMPUTED (promise); | |
0f2d19dd JB |
3748 | } |
3749 | } | |
9de87eea | 3750 | scm_unlock_mutex (SCM_PROMISE_MUTEX (promise)); |
28d52ebb | 3751 | return SCM_PROMISE_DATA (promise); |
0f2d19dd | 3752 | } |
1bbd0b84 | 3753 | #undef FUNC_NAME |
0f2d19dd | 3754 | |
445f675c | 3755 | |
a1ec6916 | 3756 | SCM_DEFINE (scm_promise_p, "promise?", 1, 0, 0, |
67e8151b | 3757 | (SCM obj), |
b380b885 | 3758 | "Return true if @var{obj} is a promise, i.e. a delayed computation\n" |
7a095584 | 3759 | "(@pxref{Delayed evaluation,,,r5rs.info,The Revised^5 Report on Scheme}).") |
1bbd0b84 | 3760 | #define FUNC_NAME s_scm_promise_p |
0f2d19dd | 3761 | { |
7888309b | 3762 | return scm_from_bool (SCM_TYP16_PREDICATE (scm_tc16_promise, obj)); |
0f2d19dd | 3763 | } |
1bbd0b84 | 3764 | #undef FUNC_NAME |
0f2d19dd | 3765 | |
445f675c | 3766 | |
a1ec6916 | 3767 | SCM_DEFINE (scm_cons_source, "cons-source", 3, 0, 0, |
1bbd0b84 | 3768 | (SCM xorig, SCM x, SCM y), |
11768c04 NJ |
3769 | "Create and return a new pair whose car and cdr are @var{x} and @var{y}.\n" |
3770 | "Any source properties associated with @var{xorig} are also associated\n" | |
3771 | "with the new pair.") | |
1bbd0b84 | 3772 | #define FUNC_NAME s_scm_cons_source |
26d5b9b4 MD |
3773 | { |
3774 | SCM p, z; | |
16d4699b | 3775 | z = scm_cons (x, y); |
26d5b9b4 MD |
3776 | /* Copy source properties possibly associated with xorig. */ |
3777 | p = scm_whash_lookup (scm_source_whash, xorig); | |
7888309b | 3778 | if (scm_is_true (p)) |
26d5b9b4 MD |
3779 | scm_whash_insert (scm_source_whash, z, p); |
3780 | return z; | |
3781 | } | |
1bbd0b84 | 3782 | #undef FUNC_NAME |
26d5b9b4 | 3783 | |
445f675c | 3784 | |
62360b89 DH |
3785 | /* The function scm_copy_tree is used to copy an expression tree to allow the |
3786 | * memoizer to modify the expression during memoization. scm_copy_tree | |
3787 | * creates deep copies of pairs and vectors, but not of any other data types, | |
3788 | * since only pairs and vectors will be parsed by the memoizer. | |
3789 | * | |
3790 | * To avoid infinite recursion due to cyclic structures, the hare-and-tortoise | |
3791 | * pattern is used to detect cycles. In fact, the pattern is used in two | |
3792 | * dimensions, vertical (indicated in the code by the variable names 'hare' | |
3793 | * and 'tortoise') and horizontal ('rabbit' and 'turtle'). In both | |
3794 | * dimensions, the hare/rabbit will take two steps when the tortoise/turtle | |
3795 | * takes one. | |
3796 | * | |
3797 | * The vertical dimension corresponds to recursive calls to function | |
3798 | * copy_tree: This happens when descending into vector elements, into cars of | |
3799 | * lists and into the cdr of an improper list. In this dimension, the | |
3800 | * tortoise follows the hare by using the processor stack: Every stack frame | |
3801 | * will hold an instance of struct t_trace. These instances are connected in | |
3802 | * a way that represents the trace of the hare, which thus can be followed by | |
3803 | * the tortoise. The tortoise will always point to struct t_trace instances | |
3804 | * relating to SCM objects that have already been copied. Thus, a cycle is | |
3805 | * detected if the tortoise and the hare point to the same object, | |
3806 | * | |
3807 | * The horizontal dimension is within one execution of copy_tree, when the | |
3808 | * function cdr's along the pairs of a list. This is the standard | |
3809 | * hare-and-tortoise implementation, found several times in guile. */ | |
3810 | ||
3811 | struct t_trace { | |
2b829bbb KR |
3812 | struct t_trace *trace; /* These pointers form a trace along the stack. */ |
3813 | SCM obj; /* The object handled at the respective stack frame.*/ | |
62360b89 DH |
3814 | }; |
3815 | ||
3816 | static SCM | |
3817 | copy_tree ( | |
3818 | struct t_trace *const hare, | |
3819 | struct t_trace *tortoise, | |
3820 | unsigned int tortoise_delay ) | |
3821 | { | |
4057a3e0 | 3822 | if (!scm_is_pair (hare->obj) && !scm_is_simple_vector (hare->obj)) |
62360b89 DH |
3823 | { |
3824 | return hare->obj; | |
3825 | } | |
3826 | else | |
3827 | { | |
3828 | /* Prepare the trace along the stack. */ | |
3829 | struct t_trace new_hare; | |
3830 | hare->trace = &new_hare; | |
3831 | ||
3832 | /* The tortoise will make its step after the delay has elapsed. Note | |
3833 | * that in contrast to the typical hare-and-tortoise pattern, the step | |
3834 | * of the tortoise happens before the hare takes its steps. This is, in | |
3835 | * principle, no problem, except for the start of the algorithm: Then, | |
5fb64383 | 3836 | * it has to be made sure that the hare actually gets its advantage of |
62360b89 DH |
3837 | * two steps. */ |
3838 | if (tortoise_delay == 0) | |
3839 | { | |
3840 | tortoise_delay = 1; | |
3841 | tortoise = tortoise->trace; | |
bc36d050 | 3842 | ASSERT_SYNTAX (!scm_is_eq (hare->obj, tortoise->obj), |
62360b89 DH |
3843 | s_bad_expression, hare->obj); |
3844 | } | |
3845 | else | |
3846 | { | |
3847 | --tortoise_delay; | |
3848 | } | |
3849 | ||
4057a3e0 | 3850 | if (scm_is_simple_vector (hare->obj)) |
62360b89 | 3851 | { |
4057a3e0 MV |
3852 | size_t length = SCM_SIMPLE_VECTOR_LENGTH (hare->obj); |
3853 | SCM new_vector = scm_c_make_vector (length, SCM_UNSPECIFIED); | |
62360b89 DH |
3854 | |
3855 | /* Each vector element is copied by recursing into copy_tree, having | |
3856 | * the tortoise follow the hare into the depths of the stack. */ | |
3857 | unsigned long int i; | |
3858 | for (i = 0; i < length; ++i) | |
3859 | { | |
3860 | SCM new_element; | |
4057a3e0 | 3861 | new_hare.obj = SCM_SIMPLE_VECTOR_REF (hare->obj, i); |
62360b89 | 3862 | new_element = copy_tree (&new_hare, tortoise, tortoise_delay); |
4057a3e0 | 3863 | SCM_SIMPLE_VECTOR_SET (new_vector, i, new_element); |
62360b89 DH |
3864 | } |
3865 | ||
3866 | return new_vector; | |
3867 | } | |
2b829bbb | 3868 | else /* scm_is_pair (hare->obj) */ |
62360b89 DH |
3869 | { |
3870 | SCM result; | |
3871 | SCM tail; | |
3872 | ||
3873 | SCM rabbit = hare->obj; | |
3874 | SCM turtle = hare->obj; | |
3875 | ||
3876 | SCM copy; | |
3877 | ||
3878 | /* The first pair of the list is treated specially, in order to | |
3879 | * preserve a potential source code position. */ | |
3880 | result = tail = scm_cons_source (rabbit, SCM_EOL, SCM_EOL); | |
3881 | new_hare.obj = SCM_CAR (rabbit); | |
3882 | copy = copy_tree (&new_hare, tortoise, tortoise_delay); | |
3883 | SCM_SETCAR (tail, copy); | |
3884 | ||
3885 | /* The remaining pairs of the list are copied by, horizontally, | |
3886 | * having the turtle follow the rabbit, and, vertically, having the | |
3887 | * tortoise follow the hare into the depths of the stack. */ | |
3888 | rabbit = SCM_CDR (rabbit); | |
a61f4e0c | 3889 | while (scm_is_pair (rabbit)) |
62360b89 DH |
3890 | { |
3891 | new_hare.obj = SCM_CAR (rabbit); | |
3892 | copy = copy_tree (&new_hare, tortoise, tortoise_delay); | |
3893 | SCM_SETCDR (tail, scm_cons (copy, SCM_UNDEFINED)); | |
3894 | tail = SCM_CDR (tail); | |
3895 | ||
3896 | rabbit = SCM_CDR (rabbit); | |
a61f4e0c | 3897 | if (scm_is_pair (rabbit)) |
62360b89 DH |
3898 | { |
3899 | new_hare.obj = SCM_CAR (rabbit); | |
3900 | copy = copy_tree (&new_hare, tortoise, tortoise_delay); | |
3901 | SCM_SETCDR (tail, scm_cons (copy, SCM_UNDEFINED)); | |
3902 | tail = SCM_CDR (tail); | |
3903 | rabbit = SCM_CDR (rabbit); | |
3904 | ||
3905 | turtle = SCM_CDR (turtle); | |
bc36d050 | 3906 | ASSERT_SYNTAX (!scm_is_eq (rabbit, turtle), |
62360b89 DH |
3907 | s_bad_expression, rabbit); |
3908 | } | |
3909 | } | |
3910 | ||
3911 | /* We have to recurse into copy_tree again for the last cdr, in | |
3912 | * order to handle the situation that it holds a vector. */ | |
3913 | new_hare.obj = rabbit; | |
3914 | copy = copy_tree (&new_hare, tortoise, tortoise_delay); | |
3915 | SCM_SETCDR (tail, copy); | |
3916 | ||
3917 | return result; | |
3918 | } | |
3919 | } | |
3920 | } | |
3921 | ||
a1ec6916 | 3922 | SCM_DEFINE (scm_copy_tree, "copy-tree", 1, 0, 0, |
1bbd0b84 | 3923 | (SCM obj), |
b380b885 | 3924 | "Recursively copy the data tree that is bound to @var{obj}, and return a\n" |
bfefbf18 | 3925 | "the new data structure. @code{copy-tree} recurses down the\n" |
b380b885 MD |
3926 | "contents of both pairs and vectors (since both cons cells and vector\n" |
3927 | "cells may point to arbitrary objects), and stops recursing when it hits\n" | |
3928 | "any other object.") | |
1bbd0b84 | 3929 | #define FUNC_NAME s_scm_copy_tree |
0f2d19dd | 3930 | { |
62360b89 DH |
3931 | /* Prepare the trace along the stack. */ |
3932 | struct t_trace trace; | |
3933 | trace.obj = obj; | |
3934 | ||
3935 | /* In function copy_tree, if the tortoise makes its step, it will do this | |
3936 | * before the hare has the chance to move. Thus, we have to make sure that | |
3937 | * the very first step of the tortoise will not happen after the hare has | |
3938 | * really made two steps. This is achieved by passing '2' as the initial | |
3939 | * delay for the tortoise. NOTE: Since cycles are unlikely, giving the hare | |
3940 | * a bigger advantage may improve performance slightly. */ | |
3941 | return copy_tree (&trace, &trace, 2); | |
0f2d19dd | 3942 | } |
1bbd0b84 | 3943 | #undef FUNC_NAME |
0f2d19dd | 3944 | |
1cc91f1b | 3945 | |
4163eb72 MV |
3946 | /* We have three levels of EVAL here: |
3947 | ||
3948 | - scm_i_eval (exp, env) | |
3949 | ||
3950 | evaluates EXP in environment ENV. ENV is a lexical environment | |
3951 | structure as used by the actual tree code evaluator. When ENV is | |
3952 | a top-level environment, then changes to the current module are | |
a513ead3 | 3953 | tracked by updating ENV so that it continues to be in sync with |
4163eb72 MV |
3954 | the current module. |
3955 | ||
3956 | - scm_primitive_eval (exp) | |
3957 | ||
3958 | evaluates EXP in the top-level environment as determined by the | |
3959 | current module. This is done by constructing a suitable | |
3960 | environment and calling scm_i_eval. Thus, changes to the | |
3961 | top-level module are tracked normally. | |
3962 | ||
9de87eea | 3963 | - scm_eval (exp, mod_or_state) |
4163eb72 | 3964 | |
9de87eea MV |
3965 | evaluates EXP while MOD_OR_STATE is the current module or current |
3966 | dynamic state (as appropriate). This is done by setting the | |
3967 | current module (or dynamic state) to MOD_OR_STATE, invoking | |
3968 | scm_primitive_eval on EXP, and then restoring the current module | |
3969 | (or dynamic state) to the value it had previously. That is, | |
3970 | while EXP is evaluated, changes to the current module (or dynamic | |
3971 | state) are tracked, but these changes do not persist when | |
4163eb72 MV |
3972 | scm_eval returns. |
3973 | ||
3974 | For each level of evals, there are two variants, distinguished by a | |
3975 | _x suffix: the ordinary variant does not modify EXP while the _x | |
3976 | variant can destructively modify EXP into something completely | |
3977 | unintelligible. A Scheme data structure passed as EXP to one of the | |
3978 | _x variants should not ever be used again for anything. So when in | |
3979 | doubt, use the ordinary variant. | |
3980 | ||
3981 | */ | |
3982 | ||
0f2d19dd | 3983 | SCM |
68d8be66 | 3984 | scm_i_eval_x (SCM exp, SCM env) |
0f2d19dd | 3985 | { |
cc95e00a | 3986 | if (scm_is_symbol (exp)) |
434f2f7a DH |
3987 | return *scm_lookupcar (scm_cons (exp, SCM_UNDEFINED), env, 1); |
3988 | else | |
0ee05b85 | 3989 | return SCM_I_XEVAL (exp, env, scm_debug_mode_p); |
0f2d19dd JB |
3990 | } |
3991 | ||
68d8be66 MD |
3992 | SCM |
3993 | scm_i_eval (SCM exp, SCM env) | |
3994 | { | |
26fb6390 | 3995 | exp = scm_copy_tree (exp); |
cc95e00a | 3996 | if (scm_is_symbol (exp)) |
434f2f7a DH |
3997 | return *scm_lookupcar (scm_cons (exp, SCM_UNDEFINED), env, 1); |
3998 | else | |
0ee05b85 | 3999 | return SCM_I_XEVAL (exp, env, scm_debug_mode_p); |
68d8be66 MD |
4000 | } |
4001 | ||
4002 | SCM | |
4163eb72 | 4003 | scm_primitive_eval_x (SCM exp) |
0f2d19dd | 4004 | { |
a513ead3 | 4005 | SCM env; |
bcdab802 | 4006 | SCM transformer = scm_current_module_transformer (); |
a513ead3 | 4007 | if (SCM_NIMP (transformer)) |
fdc28395 | 4008 | exp = scm_call_1 (transformer, exp); |
a513ead3 | 4009 | env = scm_top_level_env (scm_current_module_lookup_closure ()); |
4163eb72 | 4010 | return scm_i_eval_x (exp, env); |
0f2d19dd JB |
4011 | } |
4012 | ||
4163eb72 MV |
4013 | SCM_DEFINE (scm_primitive_eval, "primitive-eval", 1, 0, 0, |
4014 | (SCM exp), | |
2069af38 | 4015 | "Evaluate @var{exp} in the top-level environment specified by\n" |
4163eb72 MV |
4016 | "the current module.") |
4017 | #define FUNC_NAME s_scm_primitive_eval | |
4018 | { | |
a513ead3 | 4019 | SCM env; |
bcdab802 | 4020 | SCM transformer = scm_current_module_transformer (); |
7888309b | 4021 | if (scm_is_true (transformer)) |
fdc28395 | 4022 | exp = scm_call_1 (transformer, exp); |
a513ead3 | 4023 | env = scm_top_level_env (scm_current_module_lookup_closure ()); |
4163eb72 MV |
4024 | return scm_i_eval (exp, env); |
4025 | } | |
4026 | #undef FUNC_NAME | |
4027 | ||
6bff1368 | 4028 | |
68d8be66 MD |
4029 | /* Eval does not take the second arg optionally. This is intentional |
4030 | * in order to be R5RS compatible, and to prepare for the new module | |
4031 | * system, where we would like to make the choice of evaluation | |
4163eb72 | 4032 | * environment explicit. */ |
549e6ec6 | 4033 | |
4163eb72 | 4034 | SCM |
9de87eea | 4035 | scm_eval_x (SCM exp, SCM module_or_state) |
4163eb72 | 4036 | { |
9de87eea | 4037 | SCM res; |
4163eb72 | 4038 | |
661ae7ab | 4039 | scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE); |
9de87eea | 4040 | if (scm_is_dynamic_state (module_or_state)) |
661ae7ab | 4041 | scm_dynwind_current_dynamic_state (module_or_state); |
9de87eea | 4042 | else |
661ae7ab | 4043 | scm_dynwind_current_module (module_or_state); |
4163eb72 | 4044 | |
9de87eea MV |
4045 | res = scm_primitive_eval_x (exp); |
4046 | ||
661ae7ab | 4047 | scm_dynwind_end (); |
9de87eea | 4048 | return res; |
4163eb72 | 4049 | } |
09074dbf | 4050 | |
68d8be66 | 4051 | SCM_DEFINE (scm_eval, "eval", 2, 0, 0, |
9de87eea | 4052 | (SCM exp, SCM module_or_state), |
4163eb72 | 4053 | "Evaluate @var{exp}, a list representing a Scheme expression,\n" |
9de87eea MV |
4054 | "in the top-level environment specified by\n" |
4055 | "@var{module_or_state}.\n" | |
8f85c0c6 | 4056 | "While @var{exp} is evaluated (using @code{primitive-eval}),\n" |
9de87eea MV |
4057 | "@var{module_or_state} is made the current module when\n" |
4058 | "it is a module, or the current dynamic state when it is\n" | |
4059 | "a dynamic state." | |
6be1fab9 | 4060 | "Example: (eval '(+ 1 2) (interaction-environment))") |
1bbd0b84 | 4061 | #define FUNC_NAME s_scm_eval |
0f2d19dd | 4062 | { |
9de87eea MV |
4063 | SCM res; |
4064 | ||
661ae7ab | 4065 | scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE); |
9de87eea | 4066 | if (scm_is_dynamic_state (module_or_state)) |
661ae7ab | 4067 | scm_dynwind_current_dynamic_state (module_or_state); |
181f1cd7 | 4068 | else if (scm_module_system_booted_p) |
61b6542a LC |
4069 | { |
4070 | SCM_VALIDATE_MODULE (2, module_or_state); | |
4071 | scm_dynwind_current_module (module_or_state); | |
4072 | } | |
181f1cd7 | 4073 | /* otherwise if the module system isn't booted, ignore the module arg */ |
9de87eea MV |
4074 | |
4075 | res = scm_primitive_eval (exp); | |
09074dbf | 4076 | |
661ae7ab | 4077 | scm_dynwind_end (); |
9de87eea | 4078 | return res; |
0f2d19dd | 4079 | } |
1bbd0b84 | 4080 | #undef FUNC_NAME |
0f2d19dd | 4081 | |
6dbd0af5 | 4082 | |
434f2f7a | 4083 | /* At this point, deval and scm_dapply are generated. |
6dbd0af5 MD |
4084 | */ |
4085 | ||
a44a9715 | 4086 | #define DEVAL |
0ee05b85 HWN |
4087 | #include "eval.i.c" |
4088 | #undef DEVAL | |
4089 | #include "eval.i.c" | |
434f2f7a DH |
4090 | |
4091 | ||
0f2d19dd JB |
4092 | void |
4093 | scm_init_eval () | |
0f2d19dd | 4094 | { |
d1138028 MV |
4095 | scm_i_pthread_mutex_init (&source_mutex, |
4096 | scm_i_pthread_mutexattr_recursive); | |
4097 | ||
33b97402 | 4098 | scm_init_opts (scm_evaluator_traps, |
62560650 | 4099 | scm_evaluator_trap_table); |
33b97402 | 4100 | scm_init_opts (scm_eval_options_interface, |
62560650 | 4101 | scm_eval_opts); |
33b97402 | 4102 | |
f99c9c28 | 4103 | scm_tc16_promise = scm_make_smob_type ("promise", 0); |
e841c3e0 | 4104 | scm_set_smob_print (scm_tc16_promise, promise_print); |
b8229a3b | 4105 | |
a44a9715 DH |
4106 | undefineds = scm_list_1 (SCM_UNDEFINED); |
4107 | SCM_SETCDR (undefineds, undefineds); | |
4108 | scm_permanent_object (undefineds); | |
7c33806a | 4109 | |
a44a9715 | 4110 | scm_listofnull = scm_list_1 (SCM_EOL); |
0f2d19dd | 4111 | |
a44a9715 DH |
4112 | f_apply = scm_c_define_subr ("apply", scm_tc7_lsubr_2, scm_apply); |
4113 | scm_permanent_object (f_apply); | |
86d31dfe | 4114 | |
a0599745 | 4115 | #include "libguile/eval.x" |
60a49842 | 4116 | |
25eaf21a | 4117 | scm_add_feature ("delay"); |
0f2d19dd | 4118 | } |
0f2d19dd | 4119 | |
89e00824 ML |
4120 | /* |
4121 | Local Variables: | |
4122 | c-file-style: "gnu" | |
4123 | End: | |
4124 | */ | |
62560650 | 4125 |