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7081d4f9 | 1 | /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002,2003,2004,2005,2006,2007,2008,2009,2010,2011 |
dc3e203e AW |
2 | * Free Software Foundation, Inc. |
3 | * | |
4 | * This library is free software; you can redistribute it and/or | |
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. | |
8 | * | |
9 | * This library is distributed in the hope that it will be useful, but | |
10 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
12 | * Lesser General Public License for more details. | |
13 | * | |
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 | |
16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA | |
17 | * 02110-1301 USA | |
18 | */ | |
19 | ||
20 | \f | |
21 | ||
22 | #ifdef HAVE_CONFIG_H | |
23 | # include <config.h> | |
24 | #endif | |
25 | ||
26 | #include "libguile/__scm.h" | |
27 | #include "libguile/_scm.h" | |
28 | #include "libguile/continuations.h" | |
29 | #include "libguile/eq.h" | |
30 | #include "libguile/list.h" | |
31 | #include "libguile/macros.h" | |
32 | #include "libguile/expand.h" | |
33 | #include "libguile/modules.h" | |
34 | #include "libguile/srcprop.h" | |
35 | #include "libguile/ports.h" | |
36 | #include "libguile/print.h" | |
37 | #include "libguile/strings.h" | |
38 | #include "libguile/throw.h" | |
39 | #include "libguile/validate.h" | |
40 | ||
41 | ||
42 | \f | |
43 | ||
44 | ||
45 | SCM scm_exp_vtable_vtable; | |
46 | static SCM exp_vtables[SCM_NUM_EXPANDED_TYPES]; | |
47 | static size_t exp_nfields[SCM_NUM_EXPANDED_TYPES]; | |
48 | static const char* exp_names[SCM_NUM_EXPANDED_TYPES]; | |
49 | static const char** exp_field_names[SCM_NUM_EXPANDED_TYPES]; | |
50 | ||
51 | ||
52 | #define VOID(src) \ | |
53 | SCM_MAKE_EXPANDED_VOID(src) | |
54 | #define CONST(src, exp) \ | |
55 | SCM_MAKE_EXPANDED_CONST(src, exp) | |
56 | #define PRIMITIVE_REF_TYPE(src, name) \ | |
57 | SCM_MAKE_EXPANDED_PRIMITIVE_REF_TYPE(src, name) | |
58 | #define LEXICAL_REF(src, name, gensym) \ | |
59 | SCM_MAKE_EXPANDED_LEXICAL_REF(src, name, gensym) | |
60 | #define LEXICAL_SET(src, name, gensym, exp) \ | |
61 | SCM_MAKE_EXPANDED_LEXICAL_SET(src, name, gensym, exp) | |
62 | #define MODULE_REF(src, mod, name, public) \ | |
63 | SCM_MAKE_EXPANDED_MODULE_REF(src, mod, name, public) | |
64 | #define MODULE_SET(src, mod, name, public, exp) \ | |
65 | SCM_MAKE_EXPANDED_MODULE_SET(src, mod, name, public, exp) | |
66 | #define TOPLEVEL_REF(src, name) \ | |
67 | SCM_MAKE_EXPANDED_TOPLEVEL_REF(src, name) | |
68 | #define TOPLEVEL_SET(src, name, exp) \ | |
69 | SCM_MAKE_EXPANDED_TOPLEVEL_SET(src, name, exp) | |
70 | #define TOPLEVEL_DEFINE(src, name, exp) \ | |
71 | SCM_MAKE_EXPANDED_TOPLEVEL_DEFINE(src, name, exp) | |
72 | #define CONDITIONAL(src, test, consequent, alternate) \ | |
73 | SCM_MAKE_EXPANDED_CONDITIONAL(src, test, consequent, alternate) | |
7081d4f9 AW |
74 | #define CALL(src, proc, exps) \ |
75 | SCM_MAKE_EXPANDED_CALL(src, proc, exps) | |
6fc3eae4 AW |
76 | #define SEQ(src, head, tail) \ |
77 | SCM_MAKE_EXPANDED_SEQ(src, head, tail) | |
dc3e203e AW |
78 | #define LAMBDA(src, meta, body) \ |
79 | SCM_MAKE_EXPANDED_LAMBDA(src, meta, body) | |
80 | #define LAMBDA_CASE(src, req, opt, rest, kw, inits, gensyms, body, alternate) \ | |
81 | SCM_MAKE_EXPANDED_LAMBDA_CASE(src, req, opt, rest, kw, inits, gensyms, body, alternate) | |
82 | #define LET(src, names, gensyms, vals, body) \ | |
83 | SCM_MAKE_EXPANDED_LET(src, names, gensyms, vals, body) | |
fb6e61ca AW |
84 | #define LETREC(src, in_order_p, names, gensyms, vals, body) \ |
85 | SCM_MAKE_EXPANDED_LETREC(src, in_order_p, names, gensyms, vals, body) | |
dc3e203e AW |
86 | #define DYNLET(src, fluids, vals, body) \ |
87 | SCM_MAKE_EXPANDED_DYNLET(src, fluids, vals, body) | |
88 | ||
89 | #define CAR(x) SCM_CAR(x) | |
90 | #define CDR(x) SCM_CDR(x) | |
91 | #define CAAR(x) SCM_CAAR(x) | |
92 | #define CADR(x) SCM_CADR(x) | |
93 | #define CDAR(x) SCM_CDAR(x) | |
94 | #define CDDR(x) SCM_CDDR(x) | |
95 | #define CADDR(x) SCM_CADDR(x) | |
96 | #define CDDDR(x) SCM_CDDDR(x) | |
97 | #define CADDDR(x) SCM_CADDDR(x) | |
98 | ||
99 | ||
100 | static const char s_bad_expression[] = "Bad expression"; | |
101 | static const char s_expression[] = "Missing or extra expression in"; | |
102 | static const char s_missing_expression[] = "Missing expression in"; | |
103 | static const char s_extra_expression[] = "Extra expression in"; | |
104 | static const char s_empty_combination[] = "Illegal empty combination"; | |
105 | static const char s_missing_body_expression[] = "Missing body expression in"; | |
106 | static const char s_mixed_body_forms[] = "Mixed definitions and expressions in"; | |
107 | static const char s_bad_define[] = "Bad define placement"; | |
108 | static const char s_missing_clauses[] = "Missing clauses"; | |
109 | static const char s_misplaced_else_clause[] = "Misplaced else clause"; | |
110 | static const char s_bad_case_clause[] = "Bad case clause"; | |
111 | static const char s_bad_case_labels[] = "Bad case labels"; | |
112 | static const char s_duplicate_case_label[] = "Duplicate case label"; | |
113 | static const char s_bad_cond_clause[] = "Bad cond clause"; | |
114 | static const char s_missing_recipient[] = "Missing recipient in"; | |
115 | static const char s_bad_variable[] = "Bad variable"; | |
116 | static const char s_bad_bindings[] = "Bad bindings"; | |
117 | static const char s_bad_binding[] = "Bad binding"; | |
118 | static const char s_duplicate_binding[] = "Duplicate binding"; | |
119 | static const char s_bad_exit_clause[] = "Bad exit clause"; | |
120 | static const char s_bad_formals[] = "Bad formals"; | |
121 | static const char s_bad_formal[] = "Bad formal"; | |
122 | static const char s_duplicate_formal[] = "Duplicate formal"; | |
123 | static const char s_splicing[] = "Non-list result for unquote-splicing"; | |
124 | static const char s_bad_slot_number[] = "Bad slot number"; | |
125 | ||
126 | static void syntax_error (const char* const, const SCM, const SCM) SCM_NORETURN; | |
127 | ||
128 | SCM_SYMBOL (syntax_error_key, "syntax-error"); | |
129 | ||
130 | /* Shortcut macros to simplify syntax error handling. */ | |
131 | #define ASSERT_SYNTAX(cond, message, form) \ | |
132 | { if (SCM_UNLIKELY (!(cond))) \ | |
133 | syntax_error (message, form, SCM_UNDEFINED); } | |
134 | #define ASSERT_SYNTAX_2(cond, message, form, expr) \ | |
135 | { if (SCM_UNLIKELY (!(cond))) \ | |
136 | syntax_error (message, form, expr); } | |
137 | ||
138 | ||
139 | \f | |
140 | ||
141 | /* Primitive syntax. */ | |
142 | ||
143 | #define SCM_SYNTAX(STR, CFN) \ | |
144 | SCM_SNARF_HERE(static SCM CFN (SCM xorig, SCM env)) \ | |
145 | SCM_SNARF_INIT(scm_c_define (STR, scm_i_make_primitive_macro (STR, CFN))) | |
146 | ||
147 | ||
148 | /* True primitive syntax */ | |
149 | SCM_SYNTAX ("@", expand_at); | |
150 | SCM_SYNTAX ("@@", expand_atat); | |
151 | SCM_SYNTAX ("begin", expand_begin); | |
152 | SCM_SYNTAX ("define", expand_define); | |
153 | SCM_SYNTAX ("with-fluids", expand_with_fluids); | |
154 | SCM_SYNTAX ("eval-when", expand_eval_when); | |
155 | SCM_SYNTAX ("if", expand_if); | |
156 | SCM_SYNTAX ("lambda", expand_lambda); | |
157 | SCM_SYNTAX ("let", expand_let); | |
158 | SCM_SYNTAX ("quote", expand_quote); | |
159 | SCM_SYNTAX ("set!", expand_set_x); | |
160 | ||
161 | /* Convenient syntax during boot, expands to primitive syntax. Replaced after | |
162 | psyntax boots. */ | |
163 | SCM_SYNTAX ("and", expand_and); | |
164 | SCM_SYNTAX ("cond", expand_cond); | |
165 | SCM_SYNTAX ("letrec", expand_letrec); | |
826373a2 | 166 | SCM_SYNTAX ("letrec*", expand_letrec_star); |
dc3e203e AW |
167 | SCM_SYNTAX ("let*", expand_letstar); |
168 | SCM_SYNTAX ("or", expand_or); | |
169 | SCM_SYNTAX ("lambda*", expand_lambda_star); | |
170 | SCM_SYNTAX ("case-lambda", expand_case_lambda); | |
171 | SCM_SYNTAX ("case-lambda*", expand_case_lambda_star); | |
172 | ||
173 | ||
174 | SCM_GLOBAL_SYMBOL (scm_sym_apply, "apply"); | |
175 | SCM_GLOBAL_SYMBOL (scm_sym_arrow, "=>"); | |
176 | SCM_GLOBAL_SYMBOL (scm_sym_at, "@"); | |
177 | SCM_GLOBAL_SYMBOL (scm_sym_atat, "@@"); | |
178 | SCM_GLOBAL_SYMBOL (scm_sym_at_call_with_values, "@call-with-values"); | |
179 | SCM_GLOBAL_SYMBOL (scm_sym_atapply, "@apply"); | |
180 | SCM_GLOBAL_SYMBOL (scm_sym_atcall_cc, "@call-with-current-continuation"); | |
181 | SCM_GLOBAL_SYMBOL (scm_sym_begin, "begin"); | |
182 | SCM_GLOBAL_SYMBOL (scm_sym_case, "case"); | |
183 | SCM_GLOBAL_SYMBOL (scm_sym_cond, "cond"); | |
184 | SCM_GLOBAL_SYMBOL (scm_sym_define, "define"); | |
185 | SCM_GLOBAL_SYMBOL (scm_sym_at_dynamic_wind, "@dynamic-wind"); | |
186 | SCM_GLOBAL_SYMBOL (scm_sym_with_fluids, "with-fluids"); | |
187 | SCM_GLOBAL_SYMBOL (scm_sym_else, "else"); | |
188 | SCM_GLOBAL_SYMBOL (scm_sym_eval_when, "eval-when"); | |
189 | SCM_GLOBAL_SYMBOL (scm_sym_if, "if"); | |
190 | SCM_GLOBAL_SYMBOL (scm_sym_lambda, "lambda"); | |
191 | SCM_GLOBAL_SYMBOL (scm_sym_let, "let"); | |
192 | SCM_GLOBAL_SYMBOL (scm_sym_letrec, "letrec"); | |
193 | SCM_GLOBAL_SYMBOL (scm_sym_letstar, "let*"); | |
194 | SCM_GLOBAL_SYMBOL (scm_sym_or, "or"); | |
195 | SCM_GLOBAL_SYMBOL (scm_sym_at_prompt, "@prompt"); | |
196 | SCM_GLOBAL_SYMBOL (scm_sym_quote, "quote"); | |
197 | SCM_GLOBAL_SYMBOL (scm_sym_set_x, "set!"); | |
198 | SCM_SYMBOL (sym_lambda_star, "lambda*"); | |
199 | SCM_SYMBOL (sym_eval, "eval"); | |
200 | SCM_SYMBOL (sym_load, "load"); | |
201 | ||
202 | SCM_GLOBAL_SYMBOL (scm_sym_unquote, "unquote"); | |
203 | SCM_GLOBAL_SYMBOL (scm_sym_quasiquote, "quasiquote"); | |
204 | SCM_GLOBAL_SYMBOL (scm_sym_uq_splicing, "unquote-splicing"); | |
205 | ||
206 | SCM_KEYWORD (kw_allow_other_keys, "allow-other-keys"); | |
207 | SCM_KEYWORD (kw_optional, "optional"); | |
208 | SCM_KEYWORD (kw_key, "key"); | |
209 | SCM_KEYWORD (kw_rest, "rest"); | |
210 | ||
211 | ||
212 | \f | |
213 | ||
214 | ||
215 | /* Signal a syntax error. We distinguish between the form that caused the | |
216 | * error and the enclosing expression. The error message will print out as | |
217 | * shown in the following pattern. The file name and line number are only | |
218 | * given when they can be determined from the erroneous form or from the | |
219 | * enclosing expression. | |
220 | * | |
221 | * <filename>: In procedure memoization: | |
222 | * <filename>: In file <name>, line <nr>: <error-message> in <expression>. */ | |
223 | ||
224 | static void | |
225 | syntax_error (const char* const msg, const SCM form, const SCM expr) | |
226 | { | |
227 | SCM msg_string = scm_from_locale_string (msg); | |
228 | SCM filename = SCM_BOOL_F; | |
229 | SCM linenr = SCM_BOOL_F; | |
230 | const char *format; | |
231 | SCM args; | |
232 | ||
233 | if (scm_is_pair (form)) | |
234 | { | |
235 | filename = scm_source_property (form, scm_sym_filename); | |
236 | linenr = scm_source_property (form, scm_sym_line); | |
237 | } | |
238 | ||
239 | if (scm_is_false (filename) && scm_is_false (linenr) && scm_is_pair (expr)) | |
240 | { | |
241 | filename = scm_source_property (expr, scm_sym_filename); | |
242 | linenr = scm_source_property (expr, scm_sym_line); | |
243 | } | |
244 | ||
245 | if (!SCM_UNBNDP (expr)) | |
246 | { | |
247 | if (scm_is_true (filename)) | |
248 | { | |
249 | format = "In file ~S, line ~S: ~A ~S in expression ~S."; | |
250 | args = scm_list_5 (filename, linenr, msg_string, form, expr); | |
251 | } | |
252 | else if (scm_is_true (linenr)) | |
253 | { | |
254 | format = "In line ~S: ~A ~S in expression ~S."; | |
255 | args = scm_list_4 (linenr, msg_string, form, expr); | |
256 | } | |
257 | else | |
258 | { | |
259 | format = "~A ~S in expression ~S."; | |
260 | args = scm_list_3 (msg_string, form, expr); | |
261 | } | |
262 | } | |
263 | else | |
264 | { | |
265 | if (scm_is_true (filename)) | |
266 | { | |
267 | format = "In file ~S, line ~S: ~A ~S."; | |
268 | args = scm_list_4 (filename, linenr, msg_string, form); | |
269 | } | |
270 | else if (scm_is_true (linenr)) | |
271 | { | |
272 | format = "In line ~S: ~A ~S."; | |
273 | args = scm_list_3 (linenr, msg_string, form); | |
274 | } | |
275 | else | |
276 | { | |
277 | format = "~A ~S."; | |
278 | args = scm_list_2 (msg_string, form); | |
279 | } | |
280 | } | |
281 | ||
282 | scm_error (syntax_error_key, "memoization", format, args, SCM_BOOL_F); | |
283 | } | |
284 | ||
285 | ||
286 | \f | |
287 | ||
288 | ||
289 | static int | |
290 | expand_env_var_is_free (SCM env, SCM x) | |
291 | { | |
292 | for (; scm_is_pair (env); env = CDR (env)) | |
293 | if (scm_is_eq (x, CAAR (env))) | |
294 | return 0; /* bound */ | |
295 | return 1; /* free */ | |
296 | } | |
297 | ||
298 | static SCM | |
299 | expand_env_ref_macro (SCM env, SCM x) | |
300 | { | |
301 | SCM var; | |
302 | if (!expand_env_var_is_free (env, x)) | |
303 | return SCM_BOOL_F; /* lexical */ | |
304 | ||
305 | var = scm_module_variable (scm_current_module (), x); | |
306 | if (scm_is_true (var) && scm_is_true (scm_variable_bound_p (var)) | |
307 | && scm_is_true (scm_macro_p (scm_variable_ref (var)))) | |
308 | return scm_variable_ref (var); | |
309 | else | |
310 | return SCM_BOOL_F; /* anything else */ | |
311 | } | |
312 | ||
313 | static SCM | |
314 | expand_env_lexical_gensym (SCM env, SCM name) | |
315 | { | |
316 | for (; scm_is_pair (env); env = CDR (env)) | |
317 | if (scm_is_eq (name, CAAR (env))) | |
318 | return CDAR (env); /* bound */ | |
319 | return SCM_BOOL_F; /* free */ | |
320 | } | |
321 | ||
322 | static SCM | |
323 | expand_env_extend (SCM env, SCM names, SCM vars) | |
324 | { | |
325 | while (scm_is_pair (names)) | |
326 | { | |
327 | env = scm_acons (CAR (names), CAR (vars), env); | |
328 | names = CDR (names); | |
329 | vars = CDR (vars); | |
330 | } | |
331 | return env; | |
332 | } | |
333 | ||
334 | static SCM | |
335 | expand (SCM exp, SCM env) | |
336 | { | |
337 | if (scm_is_pair (exp)) | |
338 | { | |
339 | SCM car; | |
340 | scm_t_macro_primitive trans = NULL; | |
341 | SCM macro = SCM_BOOL_F; | |
342 | ||
343 | car = CAR (exp); | |
344 | if (scm_is_symbol (car)) | |
345 | macro = expand_env_ref_macro (env, car); | |
346 | ||
347 | if (scm_is_true (macro)) | |
348 | trans = scm_i_macro_primitive (macro); | |
349 | ||
350 | if (trans) | |
351 | return trans (exp, env); | |
352 | else | |
353 | { | |
354 | SCM arg_exps = SCM_EOL; | |
355 | SCM args = SCM_EOL; | |
356 | SCM proc = CAR (exp); | |
357 | ||
358 | for (arg_exps = CDR (exp); scm_is_pair (arg_exps); | |
359 | arg_exps = CDR (arg_exps)) | |
360 | args = scm_cons (expand (CAR (arg_exps), env), args); | |
361 | if (scm_is_null (arg_exps)) | |
7081d4f9 AW |
362 | return CALL (scm_source_properties (exp), |
363 | expand (proc, env), | |
364 | scm_reverse_x (args, SCM_UNDEFINED)); | |
dc3e203e AW |
365 | else |
366 | syntax_error ("expected a proper list", exp, SCM_UNDEFINED); | |
367 | } | |
368 | } | |
369 | else if (scm_is_symbol (exp)) | |
370 | { | |
371 | SCM gensym = expand_env_lexical_gensym (env, exp); | |
372 | if (scm_is_true (gensym)) | |
373 | return LEXICAL_REF (SCM_BOOL_F, exp, gensym); | |
374 | else | |
375 | return TOPLEVEL_REF (SCM_BOOL_F, exp); | |
376 | } | |
377 | else | |
378 | return CONST (SCM_BOOL_F, exp); | |
379 | } | |
380 | ||
381 | static SCM | |
382 | expand_exprs (SCM forms, const SCM env) | |
383 | { | |
384 | SCM ret = SCM_EOL; | |
385 | ||
386 | for (; !scm_is_null (forms); forms = CDR (forms)) | |
387 | ret = scm_cons (expand (CAR (forms), env), ret); | |
388 | return scm_reverse_x (ret, SCM_UNDEFINED); | |
389 | } | |
390 | ||
391 | static SCM | |
392 | expand_sequence (const SCM forms, const SCM env) | |
393 | { | |
394 | ASSERT_SYNTAX (scm_ilength (forms) >= 1, s_bad_expression, | |
395 | scm_cons (scm_sym_begin, forms)); | |
396 | if (scm_is_null (CDR (forms))) | |
397 | return expand (CAR (forms), env); | |
398 | else | |
6fc3eae4 AW |
399 | return SEQ (scm_source_properties (forms), |
400 | expand (CAR (forms), env), | |
401 | expand_sequence (CDR (forms), env)); | |
dc3e203e AW |
402 | } |
403 | ||
404 | ||
405 | \f | |
406 | ||
407 | ||
408 | static SCM | |
409 | expand_at (SCM expr, SCM env SCM_UNUSED) | |
410 | { | |
411 | ASSERT_SYNTAX (scm_ilength (expr) == 3, s_bad_expression, expr); | |
412 | ASSERT_SYNTAX (scm_ilength (CADR (expr)) > 0, s_bad_expression, expr); | |
413 | ASSERT_SYNTAX (scm_is_symbol (CADDR (expr)), s_bad_expression, expr); | |
414 | ||
415 | return MODULE_REF (scm_source_properties (expr), | |
416 | CADR (expr), CADDR (expr), SCM_BOOL_T); | |
417 | } | |
418 | ||
419 | static SCM | |
420 | expand_atat (SCM expr, SCM env SCM_UNUSED) | |
421 | { | |
422 | ASSERT_SYNTAX (scm_ilength (expr) == 3, s_bad_expression, expr); | |
423 | ASSERT_SYNTAX (scm_ilength (CADR (expr)) > 0, s_bad_expression, expr); | |
424 | ASSERT_SYNTAX (scm_is_symbol (CADDR (expr)), s_bad_expression, expr); | |
425 | ||
426 | return MODULE_REF (scm_source_properties (expr), | |
427 | CADR (expr), CADDR (expr), SCM_BOOL_F); | |
428 | } | |
429 | ||
430 | static SCM | |
431 | expand_and (SCM expr, SCM env) | |
432 | { | |
433 | const SCM cdr_expr = CDR (expr); | |
434 | ||
435 | if (scm_is_null (cdr_expr)) | |
436 | return CONST (SCM_BOOL_F, SCM_BOOL_T); | |
437 | ||
438 | ASSERT_SYNTAX (scm_is_pair (cdr_expr), s_bad_expression, expr); | |
439 | ||
440 | if (scm_is_null (CDR (cdr_expr))) | |
441 | return expand (CAR (cdr_expr), env); | |
442 | else | |
443 | return CONDITIONAL (scm_source_properties (expr), | |
444 | expand (CAR (cdr_expr), env), | |
445 | expand_and (cdr_expr, env), | |
446 | CONST (SCM_BOOL_F, SCM_BOOL_F)); | |
447 | } | |
448 | ||
449 | static SCM | |
450 | expand_begin (SCM expr, SCM env) | |
451 | { | |
452 | const SCM cdr_expr = CDR (expr); | |
453 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 1, s_bad_expression, expr); | |
454 | return expand_sequence (cdr_expr, env); | |
455 | } | |
456 | ||
457 | static SCM | |
458 | expand_cond_clauses (SCM clause, SCM rest, int elp, int alp, SCM env) | |
459 | { | |
460 | SCM test; | |
461 | const long length = scm_ilength (clause); | |
462 | ASSERT_SYNTAX (length >= 1, s_bad_cond_clause, clause); | |
463 | ||
464 | test = CAR (clause); | |
465 | if (scm_is_eq (test, scm_sym_else) && elp) | |
466 | { | |
467 | const int last_clause_p = scm_is_null (rest); | |
468 | ASSERT_SYNTAX (length >= 2, s_bad_cond_clause, clause); | |
469 | ASSERT_SYNTAX (last_clause_p, s_misplaced_else_clause, clause); | |
470 | return expand_sequence (CDR (clause), env); | |
471 | } | |
472 | ||
473 | if (scm_is_null (rest)) | |
474 | rest = VOID (SCM_BOOL_F); | |
475 | else | |
476 | rest = expand_cond_clauses (CAR (rest), CDR (rest), elp, alp, env); | |
477 | ||
478 | if (length >= 2 | |
479 | && scm_is_eq (CADR (clause), scm_sym_arrow) | |
480 | && alp) | |
481 | { | |
482 | SCM tmp = scm_gensym (scm_from_locale_string ("cond ")); | |
483 | SCM new_env = scm_acons (tmp, tmp, env); | |
484 | ASSERT_SYNTAX (length > 2, s_missing_recipient, clause); | |
485 | ASSERT_SYNTAX (length == 3, s_extra_expression, clause); | |
486 | return LET (SCM_BOOL_F, | |
487 | scm_list_1 (tmp), | |
488 | scm_list_1 (tmp), | |
489 | scm_list_1 (expand (test, env)), | |
490 | CONDITIONAL (SCM_BOOL_F, | |
491 | LEXICAL_REF (SCM_BOOL_F, tmp, tmp), | |
7081d4f9 AW |
492 | CALL (SCM_BOOL_F, |
493 | expand (CADDR (clause), new_env), | |
494 | scm_list_1 (LEXICAL_REF (SCM_BOOL_F, | |
495 | tmp, tmp))), | |
dc3e203e AW |
496 | rest)); |
497 | } | |
498 | /* FIXME length == 1 case */ | |
499 | else | |
500 | return CONDITIONAL (SCM_BOOL_F, | |
501 | expand (test, env), | |
502 | expand_sequence (CDR (clause), env), | |
503 | rest); | |
504 | } | |
505 | ||
506 | static SCM | |
507 | expand_cond (SCM expr, SCM env) | |
508 | { | |
509 | const int else_literal_p = expand_env_var_is_free (env, scm_sym_else); | |
510 | const int arrow_literal_p = expand_env_var_is_free (env, scm_sym_arrow); | |
511 | const SCM clauses = CDR (expr); | |
512 | ||
513 | ASSERT_SYNTAX (scm_ilength (clauses) >= 0, s_bad_expression, expr); | |
514 | ASSERT_SYNTAX (scm_ilength (clauses) >= 1, s_missing_clauses, expr); | |
515 | ||
516 | return expand_cond_clauses (CAR (clauses), CDR (clauses), | |
517 | else_literal_p, arrow_literal_p, env); | |
518 | } | |
519 | ||
520 | /* lone forward decl */ | |
521 | static SCM expand_lambda (SCM expr, SCM env); | |
522 | ||
523 | /* According to Section 5.2.1 of R5RS we first have to make sure that the | |
524 | variable is bound, and then perform the `(set! variable expression)' | |
525 | operation. However, EXPRESSION _can_ be evaluated before VARIABLE is | |
526 | bound. This means that EXPRESSION won't necessarily be able to assign | |
527 | values to VARIABLE as in `(define foo (begin (set! foo 1) (+ foo 1)))'. */ | |
528 | static SCM | |
529 | expand_define (SCM expr, SCM env) | |
530 | { | |
531 | const SCM cdr_expr = CDR (expr); | |
532 | SCM body; | |
533 | SCM variable; | |
534 | ||
535 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
536 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); | |
537 | ASSERT_SYNTAX (!scm_is_pair (env), s_bad_define, expr); | |
538 | ||
539 | body = CDR (cdr_expr); | |
540 | variable = CAR (cdr_expr); | |
541 | ||
542 | if (scm_is_pair (variable)) | |
543 | { | |
544 | ASSERT_SYNTAX_2 (scm_is_symbol (CAR (variable)), s_bad_variable, variable, expr); | |
545 | return TOPLEVEL_DEFINE | |
546 | (scm_source_properties (expr), | |
547 | CAR (variable), | |
548 | expand_lambda (scm_cons (scm_sym_lambda, scm_cons (CDR (variable), body)), | |
549 | env)); | |
550 | } | |
551 | ASSERT_SYNTAX_2 (scm_is_symbol (variable), s_bad_variable, variable, expr); | |
552 | ASSERT_SYNTAX (scm_ilength (body) == 1, s_expression, expr); | |
553 | return TOPLEVEL_DEFINE (scm_source_properties (expr), variable, | |
554 | expand (CAR (body), env)); | |
555 | } | |
556 | ||
557 | static SCM | |
558 | expand_with_fluids (SCM expr, SCM env) | |
559 | { | |
560 | SCM binds, fluids, vals; | |
561 | ASSERT_SYNTAX (scm_ilength (expr) >= 3, s_bad_expression, expr); | |
562 | binds = CADR (expr); | |
563 | ASSERT_SYNTAX_2 (scm_ilength (binds) >= 0, s_bad_bindings, binds, expr); | |
564 | for (fluids = SCM_EOL, vals = SCM_EOL; | |
565 | scm_is_pair (binds); | |
566 | binds = CDR (binds)) | |
567 | { | |
568 | SCM binding = CAR (binds); | |
569 | ASSERT_SYNTAX_2 (scm_ilength (CAR (binds)) == 2, s_bad_binding, | |
570 | binding, expr); | |
571 | fluids = scm_cons (expand (CAR (binding), env), fluids); | |
572 | vals = scm_cons (expand (CADR (binding), env), vals); | |
573 | } | |
574 | ||
575 | return DYNLET (scm_source_properties (expr), | |
576 | scm_reverse_x (fluids, SCM_UNDEFINED), | |
577 | scm_reverse_x (vals, SCM_UNDEFINED), | |
578 | expand_sequence (CDDR (expr), env)); | |
579 | } | |
580 | ||
581 | static SCM | |
582 | expand_eval_when (SCM expr, SCM env) | |
583 | { | |
584 | ASSERT_SYNTAX (scm_ilength (expr) >= 3, s_bad_expression, expr); | |
585 | ASSERT_SYNTAX (scm_ilength (CADR (expr)) > 0, s_bad_expression, expr); | |
586 | ||
587 | if (scm_is_true (scm_memq (sym_eval, CADR (expr))) | |
588 | || scm_is_true (scm_memq (sym_load, CADR (expr)))) | |
589 | return expand_sequence (CDDR (expr), env); | |
590 | else | |
591 | return VOID (scm_source_properties (expr)); | |
592 | } | |
593 | ||
594 | static SCM | |
595 | expand_if (SCM expr, SCM env SCM_UNUSED) | |
596 | { | |
597 | const SCM cdr_expr = CDR (expr); | |
598 | const long length = scm_ilength (cdr_expr); | |
599 | ASSERT_SYNTAX (length == 2 || length == 3, s_expression, expr); | |
600 | return CONDITIONAL (scm_source_properties (expr), | |
601 | expand (CADR (expr), env), | |
602 | expand (CADDR (expr), env), | |
603 | ((length == 3) | |
604 | ? expand (CADDDR (expr), env) | |
605 | : VOID (SCM_BOOL_F))); | |
606 | } | |
607 | ||
608 | /* A helper function for expand_lambda to support checking for duplicate | |
609 | * formal arguments: Return true if OBJ is `eq?' to one of the elements of | |
610 | * LIST or to the CDR of the last cons. Therefore, LIST may have any of the | |
611 | * forms that a formal argument can have: | |
612 | * <rest>, (<arg1> ...), (<arg1> ... . <rest>) */ | |
613 | static int | |
614 | c_improper_memq (SCM obj, SCM list) | |
615 | { | |
616 | for (; scm_is_pair (list); list = CDR (list)) | |
617 | { | |
618 | if (scm_is_eq (CAR (list), obj)) | |
619 | return 1; | |
620 | } | |
621 | return scm_is_eq (list, obj); | |
622 | } | |
623 | ||
624 | static SCM | |
625 | expand_lambda_case (SCM clause, SCM alternate, SCM env) | |
626 | { | |
627 | SCM formals; | |
628 | SCM rest; | |
629 | SCM req = SCM_EOL; | |
630 | SCM vars = SCM_EOL; | |
631 | SCM body; | |
632 | int nreq = 0; | |
633 | ||
634 | ASSERT_SYNTAX (scm_is_pair (clause) && scm_is_pair (CDR (clause)), | |
635 | s_bad_expression, scm_cons (scm_sym_lambda, clause)); | |
636 | ||
637 | /* Before iterating the list of formal arguments, make sure the formals | |
638 | * actually are given as either a symbol or a non-cyclic list. */ | |
639 | formals = CAR (clause); | |
640 | if (scm_is_pair (formals)) | |
641 | { | |
642 | /* Dirk:FIXME:: We should check for a cyclic list of formals, and if | |
643 | * detected, report a 'Bad formals' error. */ | |
644 | } | |
645 | else | |
646 | ASSERT_SYNTAX_2 (scm_is_symbol (formals) || scm_is_null (formals), | |
647 | s_bad_formals, formals, scm_cons (scm_sym_lambda, clause)); | |
648 | ||
649 | /* Now iterate the list of formal arguments to check if all formals are | |
650 | * symbols, and that there are no duplicates. */ | |
651 | while (scm_is_pair (formals)) | |
652 | { | |
653 | const SCM formal = CAR (formals); | |
654 | formals = CDR (formals); | |
655 | ASSERT_SYNTAX_2 (scm_is_symbol (formal), s_bad_formal, formal, | |
656 | scm_cons (scm_sym_lambda, clause)); | |
657 | ASSERT_SYNTAX_2 (!c_improper_memq (formal, formals), s_duplicate_formal, | |
658 | formal, scm_cons (scm_sym_lambda, clause)); | |
659 | nreq++; | |
660 | req = scm_cons (formal, req); | |
661 | vars = scm_cons (scm_gensym (SCM_UNDEFINED), vars); | |
662 | env = scm_acons (formal, CAR (vars), env); | |
663 | } | |
664 | ||
665 | ASSERT_SYNTAX_2 (scm_is_null (formals) || scm_is_symbol (formals), | |
666 | s_bad_formal, formals, scm_cons (scm_sym_lambda, clause)); | |
667 | if (scm_is_symbol (formals)) | |
668 | { | |
669 | rest = formals; | |
670 | vars = scm_cons (scm_gensym (SCM_UNDEFINED), vars); | |
671 | env = scm_acons (rest, CAR (vars), env); | |
672 | } | |
673 | else | |
674 | rest = SCM_BOOL_F; | |
675 | ||
676 | body = expand_sequence (CDR (clause), env); | |
677 | req = scm_reverse_x (req, SCM_UNDEFINED); | |
678 | vars = scm_reverse_x (vars, SCM_UNDEFINED); | |
679 | ||
680 | if (scm_is_true (alternate) && !(SCM_EXPANDED_P (alternate) && SCM_EXPANDED_TYPE (alternate) == SCM_EXPANDED_LAMBDA_CASE)) | |
681 | abort (); | |
682 | ||
683 | return LAMBDA_CASE (SCM_BOOL_F, req, SCM_BOOL_F, rest, SCM_BOOL_F, | |
684 | SCM_EOL, vars, body, alternate); | |
685 | } | |
686 | ||
687 | static SCM | |
688 | expand_lambda (SCM expr, SCM env) | |
689 | { | |
690 | return LAMBDA (scm_source_properties (expr), | |
691 | SCM_EOL, | |
692 | expand_lambda_case (CDR (expr), SCM_BOOL_F, env)); | |
693 | } | |
694 | ||
695 | static SCM | |
696 | expand_lambda_star_case (SCM clause, SCM alternate, SCM env) | |
697 | { | |
698 | SCM req, opt, kw, allow_other_keys, rest, formals, vars, body, tmp; | |
632ddbf0 | 699 | SCM inits; |
dc3e203e AW |
700 | int nreq, nopt; |
701 | ||
702 | const long length = scm_ilength (clause); | |
703 | ASSERT_SYNTAX (length >= 1, s_bad_expression, | |
704 | scm_cons (sym_lambda_star, clause)); | |
705 | ASSERT_SYNTAX (length >= 2, s_missing_expression, | |
706 | scm_cons (sym_lambda_star, clause)); | |
707 | ||
708 | formals = CAR (clause); | |
709 | body = CDR (clause); | |
710 | ||
711 | nreq = nopt = 0; | |
712 | req = opt = kw = SCM_EOL; | |
713 | rest = allow_other_keys = SCM_BOOL_F; | |
714 | ||
715 | while (scm_is_pair (formals) && scm_is_symbol (CAR (formals))) | |
716 | { | |
717 | nreq++; | |
718 | req = scm_cons (CAR (formals), req); | |
719 | formals = scm_cdr (formals); | |
720 | } | |
721 | ||
722 | if (scm_is_pair (formals) && scm_is_eq (CAR (formals), kw_optional)) | |
723 | { | |
724 | formals = CDR (formals); | |
725 | while (scm_is_pair (formals) | |
726 | && (scm_is_symbol (CAR (formals)) || scm_is_pair (CAR (formals)))) | |
727 | { | |
728 | nopt++; | |
729 | opt = scm_cons (CAR (formals), opt); | |
730 | formals = scm_cdr (formals); | |
731 | } | |
732 | } | |
733 | ||
734 | if (scm_is_pair (formals) && scm_is_eq (CAR (formals), kw_key)) | |
735 | { | |
736 | formals = CDR (formals); | |
737 | while (scm_is_pair (formals) | |
738 | && (scm_is_symbol (CAR (formals)) || scm_is_pair (CAR (formals)))) | |
739 | { | |
740 | kw = scm_cons (CAR (formals), kw); | |
741 | formals = scm_cdr (formals); | |
742 | } | |
743 | } | |
744 | ||
745 | if (scm_is_pair (formals) && scm_is_eq (CAR (formals), kw_allow_other_keys)) | |
746 | { | |
747 | formals = CDR (formals); | |
748 | allow_other_keys = SCM_BOOL_T; | |
749 | } | |
750 | ||
751 | if (scm_is_pair (formals) && scm_is_eq (CAR (formals), kw_rest)) | |
752 | { | |
753 | ASSERT_SYNTAX (scm_ilength (formals) == 2, s_bad_formals, | |
754 | CAR (clause)); | |
755 | rest = CADR (formals); | |
756 | } | |
757 | else if (scm_is_symbol (formals)) | |
758 | rest = formals; | |
759 | else | |
760 | { | |
761 | ASSERT_SYNTAX (scm_is_null (formals), s_bad_formals, CAR (clause)); | |
762 | rest = SCM_BOOL_F; | |
763 | } | |
764 | ||
765 | /* Now, iterate through them a second time, building up an expansion-time | |
766 | environment, checking, expanding and canonicalizing the opt/kw init forms, | |
767 | and eventually memoizing the body as well. Note that the rest argument, if | |
768 | any, is expanded before keyword args, thus necessitating the second | |
769 | pass. | |
770 | ||
771 | Also note that the specific environment during expansion of init | |
772 | expressions here needs to coincide with the environment when psyntax | |
773 | expands. A lot of effort for something that is only used in the bootstrap | |
774 | expandr, you say? Yes. Yes it is. | |
775 | */ | |
776 | ||
777 | vars = SCM_EOL; | |
778 | req = scm_reverse_x (req, SCM_EOL); | |
779 | for (tmp = req; scm_is_pair (tmp); tmp = scm_cdr (tmp)) | |
780 | { | |
781 | vars = scm_cons (scm_gensym (SCM_UNDEFINED), vars); | |
782 | env = scm_acons (CAR (tmp), CAR (vars), env); | |
783 | } | |
784 | ||
785 | /* Build up opt inits and env */ | |
786 | inits = SCM_EOL; | |
787 | opt = scm_reverse_x (opt, SCM_EOL); | |
788 | for (tmp = opt; scm_is_pair (tmp); tmp = scm_cdr (tmp)) | |
789 | { | |
790 | SCM x = CAR (tmp); | |
791 | vars = scm_cons (scm_gensym (SCM_UNDEFINED), vars); | |
792 | env = scm_acons (x, CAR (vars), env); | |
793 | if (scm_is_symbol (x)) | |
794 | inits = scm_cons (CONST (SCM_BOOL_F, SCM_BOOL_F), inits); | |
795 | else | |
796 | { | |
797 | ASSERT_SYNTAX (scm_ilength (x) == 2 && scm_is_symbol (CAR (x)), | |
798 | s_bad_formals, CAR (clause)); | |
799 | inits = scm_cons (expand (CADR (x), env), inits); | |
800 | } | |
801 | env = scm_acons (scm_is_symbol (x) ? x : CAR (x), CAR (vars), env); | |
802 | } | |
803 | if (scm_is_null (opt)) | |
804 | opt = SCM_BOOL_F; | |
805 | ||
806 | /* Process rest before keyword args */ | |
807 | if (scm_is_true (rest)) | |
808 | { | |
809 | vars = scm_cons (scm_gensym (SCM_UNDEFINED), vars); | |
810 | env = scm_acons (rest, CAR (vars), env); | |
811 | } | |
812 | ||
632ddbf0 | 813 | /* Build up kw inits, env, and kw-canon list */ |
dc3e203e AW |
814 | if (scm_is_null (kw)) |
815 | kw = SCM_BOOL_F; | |
816 | else | |
817 | { | |
632ddbf0 | 818 | SCM kw_canon = SCM_EOL; |
dc3e203e AW |
819 | kw = scm_reverse_x (kw, SCM_UNDEFINED); |
820 | for (tmp = kw; scm_is_pair (tmp); tmp = scm_cdr (tmp)) | |
821 | { | |
822 | SCM x, sym, k, init; | |
823 | x = CAR (tmp); | |
824 | if (scm_is_symbol (x)) | |
825 | { | |
826 | sym = x; | |
827 | init = SCM_BOOL_F; | |
828 | k = scm_symbol_to_keyword (sym); | |
829 | } | |
830 | else if (scm_ilength (x) == 2 && scm_is_symbol (CAR (x))) | |
831 | { | |
832 | sym = CAR (x); | |
833 | init = CADR (x); | |
834 | k = scm_symbol_to_keyword (sym); | |
835 | } | |
836 | else if (scm_ilength (x) == 3 && scm_is_symbol (CAR (x)) | |
837 | && scm_is_keyword (CADDR (x))) | |
838 | { | |
839 | sym = CAR (x); | |
840 | init = CADR (x); | |
841 | k = CADDR (x); | |
842 | } | |
843 | else | |
844 | syntax_error (s_bad_formals, CAR (clause), SCM_UNDEFINED); | |
845 | ||
dc3e203e AW |
846 | inits = scm_cons (expand (init, env), inits); |
847 | vars = scm_cons (scm_gensym (SCM_UNDEFINED), vars); | |
632ddbf0 | 848 | kw_canon = scm_cons (scm_list_3 (k, sym, CAR (vars)), kw_canon); |
dc3e203e AW |
849 | env = scm_acons (sym, CAR (vars), env); |
850 | } | |
632ddbf0 AW |
851 | kw_canon = scm_reverse_x (kw_canon, SCM_UNDEFINED); |
852 | kw = scm_cons (allow_other_keys, kw_canon); | |
dc3e203e AW |
853 | } |
854 | ||
855 | /* We should check for no duplicates, but given that psyntax does this | |
856 | already, we can punt on it here... */ | |
857 | ||
858 | vars = scm_reverse_x (vars, SCM_UNDEFINED); | |
859 | inits = scm_reverse_x (inits, SCM_UNDEFINED); | |
860 | body = expand_sequence (body, env); | |
861 | ||
862 | return LAMBDA_CASE (SCM_BOOL_F, req, opt, rest, kw, inits, vars, body, | |
863 | alternate); | |
864 | } | |
865 | ||
866 | static SCM | |
867 | expand_lambda_star (SCM expr, SCM env) | |
868 | { | |
869 | return LAMBDA (scm_source_properties (expr), | |
870 | SCM_EOL, | |
871 | expand_lambda_star_case (CDR (expr), SCM_BOOL_F, env)); | |
872 | } | |
873 | ||
874 | static SCM | |
875 | expand_case_lambda_clauses (SCM expr, SCM rest, SCM env) | |
876 | { | |
877 | SCM alt; | |
878 | ||
879 | if (scm_is_pair (rest)) | |
880 | alt = expand_case_lambda_clauses (CAR (rest), CDR (rest), env); | |
881 | else | |
882 | alt = SCM_BOOL_F; | |
883 | ||
884 | return expand_lambda_case (expr, alt, env); | |
885 | } | |
886 | ||
887 | static SCM | |
888 | expand_case_lambda (SCM expr, SCM env) | |
889 | { | |
890 | ASSERT_SYNTAX (scm_is_pair (CDR (expr)), s_missing_expression, expr); | |
891 | ||
892 | return LAMBDA (scm_source_properties (expr), | |
893 | SCM_EOL, | |
894 | expand_case_lambda_clauses (CADR (expr), CDDR (expr), env)); | |
895 | } | |
896 | ||
897 | static SCM | |
898 | expand_case_lambda_star_clauses (SCM expr, SCM rest, SCM env) | |
899 | { | |
900 | SCM alt; | |
901 | ||
902 | if (scm_is_pair (rest)) | |
903 | alt = expand_case_lambda_star_clauses (CAR (rest), CDR (rest), env); | |
904 | else | |
905 | alt = SCM_BOOL_F; | |
906 | ||
907 | return expand_lambda_star_case (expr, alt, env); | |
908 | } | |
909 | ||
910 | static SCM | |
911 | expand_case_lambda_star (SCM expr, SCM env) | |
912 | { | |
913 | ASSERT_SYNTAX (scm_is_pair (CDR (expr)), s_missing_expression, expr); | |
914 | ||
915 | return LAMBDA (scm_source_properties (expr), | |
916 | SCM_EOL, | |
917 | expand_case_lambda_star_clauses (CADR (expr), CDDR (expr), env)); | |
918 | } | |
919 | ||
920 | /* Check if the format of the bindings is ((<symbol> <init-form>) ...). */ | |
921 | static void | |
922 | check_bindings (const SCM bindings, const SCM expr) | |
923 | { | |
924 | SCM binding_idx; | |
925 | ||
926 | ASSERT_SYNTAX_2 (scm_ilength (bindings) >= 0, | |
927 | s_bad_bindings, bindings, expr); | |
928 | ||
929 | binding_idx = bindings; | |
930 | for (; !scm_is_null (binding_idx); binding_idx = CDR (binding_idx)) | |
931 | { | |
932 | SCM name; /* const */ | |
933 | ||
934 | const SCM binding = CAR (binding_idx); | |
935 | ASSERT_SYNTAX_2 (scm_ilength (binding) == 2, | |
936 | s_bad_binding, binding, expr); | |
937 | ||
938 | name = CAR (binding); | |
939 | ASSERT_SYNTAX_2 (scm_is_symbol (name), s_bad_variable, name, expr); | |
940 | } | |
941 | } | |
942 | ||
943 | /* The bindings, which must have the format ((v1 i1) (v2 i2) ... (vn in)), are | |
944 | * transformed to the lists (vn .. v2 v1) and (i1 i2 ... in). If a duplicate | |
945 | * variable name is detected, an error is signalled. */ | |
946 | static void | |
947 | transform_bindings (const SCM bindings, const SCM expr, | |
948 | SCM *const names, SCM *const vars, SCM *const initptr) | |
949 | { | |
950 | SCM rnames = SCM_EOL; | |
951 | SCM rvars = SCM_EOL; | |
952 | SCM rinits = SCM_EOL; | |
953 | SCM binding_idx = bindings; | |
954 | for (; !scm_is_null (binding_idx); binding_idx = CDR (binding_idx)) | |
955 | { | |
956 | const SCM binding = CAR (binding_idx); | |
957 | const SCM CDR_binding = CDR (binding); | |
958 | const SCM name = CAR (binding); | |
959 | ASSERT_SYNTAX_2 (scm_is_false (scm_c_memq (name, rnames)), | |
960 | s_duplicate_binding, name, expr); | |
961 | rnames = scm_cons (name, rnames); | |
962 | rvars = scm_cons (scm_gensym (SCM_UNDEFINED), rvars); | |
963 | rinits = scm_cons (CAR (CDR_binding), rinits); | |
964 | } | |
965 | *names = scm_reverse_x (rnames, SCM_UNDEFINED); | |
966 | *vars = scm_reverse_x (rvars, SCM_UNDEFINED); | |
967 | *initptr = scm_reverse_x (rinits, SCM_UNDEFINED); | |
968 | } | |
969 | ||
970 | /* FIXME: Remove named let in this boot expander. */ | |
971 | static SCM | |
972 | expand_named_let (const SCM expr, SCM env) | |
973 | { | |
974 | SCM var_names, var_syms, inits; | |
975 | SCM inner_env; | |
976 | SCM name_sym; | |
977 | ||
978 | const SCM cdr_expr = CDR (expr); | |
979 | const SCM name = CAR (cdr_expr); | |
980 | const SCM cddr_expr = CDR (cdr_expr); | |
981 | const SCM bindings = CAR (cddr_expr); | |
982 | check_bindings (bindings, expr); | |
983 | ||
984 | transform_bindings (bindings, expr, &var_names, &var_syms, &inits); | |
985 | name_sym = scm_gensym (SCM_UNDEFINED); | |
986 | inner_env = scm_acons (name, name_sym, env); | |
987 | inner_env = expand_env_extend (inner_env, var_names, var_syms); | |
988 | ||
989 | return LETREC | |
fb6e61ca | 990 | (scm_source_properties (expr), SCM_BOOL_F, |
dc3e203e AW |
991 | scm_list_1 (name), scm_list_1 (name_sym), |
992 | scm_list_1 (LAMBDA (SCM_BOOL_F, | |
993 | SCM_EOL, | |
994 | LAMBDA_CASE (SCM_BOOL_F, var_names, SCM_BOOL_F, SCM_BOOL_F, | |
995 | SCM_BOOL_F, SCM_BOOL_F, var_syms, | |
996 | expand_sequence (CDDDR (expr), inner_env), | |
997 | SCM_BOOL_F))), | |
7081d4f9 AW |
998 | CALL (SCM_BOOL_F, |
999 | LEXICAL_REF (SCM_BOOL_F, name, name_sym), | |
1000 | expand_exprs (inits, env))); | |
dc3e203e AW |
1001 | } |
1002 | ||
1003 | static SCM | |
1004 | expand_let (SCM expr, SCM env) | |
1005 | { | |
1006 | SCM bindings; | |
1007 | ||
1008 | const SCM cdr_expr = CDR (expr); | |
1009 | const long length = scm_ilength (cdr_expr); | |
1010 | ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); | |
1011 | ASSERT_SYNTAX (length >= 2, s_missing_expression, expr); | |
1012 | ||
1013 | bindings = CAR (cdr_expr); | |
1014 | if (scm_is_symbol (bindings)) | |
1015 | { | |
1016 | ASSERT_SYNTAX (length >= 3, s_missing_expression, expr); | |
1017 | return expand_named_let (expr, env); | |
1018 | } | |
1019 | ||
1020 | check_bindings (bindings, expr); | |
1021 | if (scm_is_null (bindings)) | |
1022 | return expand_sequence (CDDR (expr), env); | |
1023 | else | |
1024 | { | |
1025 | SCM var_names, var_syms, inits; | |
1026 | transform_bindings (bindings, expr, &var_names, &var_syms, &inits); | |
1027 | return LET (SCM_BOOL_F, | |
1028 | var_names, var_syms, expand_exprs (inits, env), | |
1029 | expand_sequence (CDDR (expr), | |
1030 | expand_env_extend (env, var_names, | |
1031 | var_syms))); | |
1032 | } | |
1033 | } | |
1034 | ||
1035 | static SCM | |
826373a2 | 1036 | expand_letrec_helper (SCM expr, SCM env, SCM in_order_p) |
dc3e203e AW |
1037 | { |
1038 | SCM bindings; | |
1039 | ||
1040 | const SCM cdr_expr = CDR (expr); | |
1041 | const long length = scm_ilength (cdr_expr); | |
1042 | ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); | |
1043 | ASSERT_SYNTAX (length >= 2, s_missing_expression, expr); | |
1044 | ||
1045 | bindings = CAR (cdr_expr); | |
1046 | check_bindings (bindings, expr); | |
1047 | if (scm_is_null (bindings)) | |
1048 | return expand_sequence (CDDR (expr), env); | |
1049 | else | |
1050 | { | |
1051 | SCM var_names, var_syms, inits; | |
1052 | transform_bindings (bindings, expr, &var_names, &var_syms, &inits); | |
1053 | env = expand_env_extend (env, var_names, var_syms); | |
826373a2 | 1054 | return LETREC (SCM_BOOL_F, in_order_p, |
dc3e203e AW |
1055 | var_names, var_syms, expand_exprs (inits, env), |
1056 | expand_sequence (CDDR (expr), env)); | |
1057 | } | |
1058 | } | |
1059 | ||
826373a2 AW |
1060 | static SCM |
1061 | expand_letrec (SCM expr, SCM env) | |
1062 | { | |
1063 | return expand_letrec_helper (expr, env, SCM_BOOL_F); | |
1064 | } | |
1065 | ||
1066 | static SCM | |
1067 | expand_letrec_star (SCM expr, SCM env) | |
1068 | { | |
1069 | return expand_letrec_helper (expr, env, SCM_BOOL_T); | |
1070 | } | |
1071 | ||
dc3e203e AW |
1072 | static SCM |
1073 | expand_letstar_clause (SCM bindings, SCM body, SCM env SCM_UNUSED) | |
1074 | { | |
1075 | if (scm_is_null (bindings)) | |
1076 | return expand_sequence (body, env); | |
1077 | else | |
1078 | { | |
1079 | SCM bind, name, sym, init; | |
1080 | ||
1081 | ASSERT_SYNTAX (scm_is_pair (bindings), s_bad_expression, bindings); | |
1082 | bind = CAR (bindings); | |
1083 | ASSERT_SYNTAX (scm_ilength (bind) == 2, s_bad_binding, bind); | |
1084 | name = CAR (bind); | |
1085 | sym = scm_gensym (SCM_UNDEFINED); | |
1086 | init = CADR (bind); | |
1087 | ||
1088 | return LET (SCM_BOOL_F, scm_list_1 (name), scm_list_1 (sym), | |
1089 | scm_list_1 (expand (init, env)), | |
1090 | expand_letstar_clause (CDR (bindings), body, | |
1091 | scm_acons (name, sym, env))); | |
1092 | } | |
1093 | } | |
1094 | ||
1095 | static SCM | |
1096 | expand_letstar (SCM expr, SCM env SCM_UNUSED) | |
1097 | { | |
1098 | const SCM cdr_expr = CDR (expr); | |
1099 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1100 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 2, s_missing_expression, expr); | |
1101 | ||
1102 | return expand_letstar_clause (CADR (expr), CDDR (expr), env); | |
1103 | } | |
1104 | ||
1105 | static SCM | |
1106 | expand_or (SCM expr, SCM env SCM_UNUSED) | |
1107 | { | |
1108 | SCM tail = CDR (expr); | |
1109 | const long length = scm_ilength (tail); | |
1110 | ||
1111 | ASSERT_SYNTAX (length >= 0, s_bad_expression, expr); | |
1112 | ||
1113 | if (scm_is_null (CDR (expr))) | |
1114 | return CONST (SCM_BOOL_F, SCM_BOOL_F); | |
1115 | else | |
1116 | { | |
1117 | SCM tmp = scm_gensym (SCM_UNDEFINED); | |
1118 | return LET (SCM_BOOL_F, | |
1119 | scm_list_1 (tmp), scm_list_1 (tmp), | |
1120 | scm_list_1 (expand (CADR (expr), env)), | |
1121 | CONDITIONAL (SCM_BOOL_F, | |
1122 | LEXICAL_REF (SCM_BOOL_F, tmp, tmp), | |
1123 | LEXICAL_REF (SCM_BOOL_F, tmp, tmp), | |
1124 | expand_or (CDR (expr), | |
1125 | scm_acons (tmp, tmp, env)))); | |
1126 | } | |
1127 | } | |
1128 | ||
1129 | static SCM | |
1130 | expand_quote (SCM expr, SCM env SCM_UNUSED) | |
1131 | { | |
1132 | SCM quotee; | |
1133 | ||
1134 | const SCM cdr_expr = CDR (expr); | |
1135 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1136 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 1, s_expression, expr); | |
1137 | quotee = CAR (cdr_expr); | |
1138 | return CONST (scm_source_properties (expr), quotee); | |
1139 | } | |
1140 | ||
1141 | static SCM | |
1142 | expand_set_x (SCM expr, SCM env) | |
1143 | { | |
1144 | SCM variable; | |
1145 | SCM vmem; | |
1146 | ||
1147 | const SCM cdr_expr = CDR (expr); | |
1148 | ASSERT_SYNTAX (scm_ilength (cdr_expr) >= 0, s_bad_expression, expr); | |
1149 | ASSERT_SYNTAX (scm_ilength (cdr_expr) == 2, s_expression, expr); | |
1150 | variable = CAR (cdr_expr); | |
1151 | vmem = expand (variable, env); | |
1152 | ||
1153 | switch (SCM_EXPANDED_TYPE (vmem)) | |
1154 | { | |
1155 | case SCM_EXPANDED_LEXICAL_REF: | |
1156 | return LEXICAL_SET (scm_source_properties (expr), | |
1157 | SCM_EXPANDED_REF (vmem, LEXICAL_REF, NAME), | |
1158 | SCM_EXPANDED_REF (vmem, LEXICAL_REF, GENSYM), | |
1159 | expand (CADDR (expr), env)); | |
1160 | case SCM_EXPANDED_TOPLEVEL_REF: | |
1161 | return TOPLEVEL_SET (scm_source_properties (expr), | |
1162 | SCM_EXPANDED_REF (vmem, TOPLEVEL_REF, NAME), | |
1163 | expand (CADDR (expr), env)); | |
1164 | case SCM_EXPANDED_MODULE_REF: | |
1165 | return MODULE_SET (scm_source_properties (expr), | |
1166 | SCM_EXPANDED_REF (vmem, MODULE_REF, MOD), | |
1167 | SCM_EXPANDED_REF (vmem, MODULE_REF, NAME), | |
1168 | SCM_EXPANDED_REF (vmem, MODULE_REF, PUBLIC), | |
1169 | expand (CADDR (expr), env)); | |
1170 | default: | |
1171 | syntax_error (s_bad_variable, variable, expr); | |
1172 | } | |
1173 | } | |
1174 | ||
1175 | ||
1176 | \f | |
1177 | ||
a310a1d1 AW |
1178 | /* This is the boot expander. It is later replaced with psyntax's sc-expand. */ |
1179 | SCM_DEFINE (scm_macroexpand, "macroexpand", 1, 0, 0, | |
dc3e203e AW |
1180 | (SCM exp), |
1181 | "Expand the expression @var{exp}.") | |
1182 | #define FUNC_NAME s_scm_macroexpand | |
1183 | { | |
1184 | return expand (exp, scm_current_module ()); | |
1185 | } | |
1186 | #undef FUNC_NAME | |
1187 | ||
a310a1d1 AW |
1188 | SCM_DEFINE (scm_macroexpanded_p, "macroexpanded?", 1, 0, 0, |
1189 | (SCM exp), | |
1190 | "Return @code{#t} if @var{exp} is an expanded expression.") | |
1191 | #define FUNC_NAME s_scm_macroexpanded_p | |
1192 | { | |
1193 | return scm_from_bool (SCM_EXPANDED_P (exp)); | |
1194 | } | |
1195 | #undef FUNC_NAME | |
1196 | ||
dc3e203e AW |
1197 | |
1198 | \f | |
1199 | ||
1200 | #define DEFINE_NAMES(type) \ | |
1201 | { \ | |
1202 | static const char *fields[] = SCM_EXPANDED_##type##_FIELD_NAMES; \ | |
1203 | exp_field_names[SCM_EXPANDED_##type] = fields; \ | |
1204 | exp_names[SCM_EXPANDED_##type] = SCM_EXPANDED_##type##_TYPE_NAME; \ | |
1205 | exp_nfields[SCM_EXPANDED_##type] = SCM_NUM_EXPANDED_##type##_FIELDS; \ | |
1206 | } | |
1207 | ||
1208 | static SCM | |
1209 | make_exp_vtable (size_t n) | |
1210 | { | |
1211 | SCM layout, printer, name, code, fields; | |
1212 | ||
1213 | layout = scm_string_to_symbol | |
1214 | (scm_string_append (scm_make_list (scm_from_size_t (exp_nfields[n]), | |
1215 | scm_from_locale_string ("pw")))); | |
1216 | printer = SCM_BOOL_F; | |
1217 | name = scm_from_locale_symbol (exp_names[n]); | |
1218 | code = scm_from_size_t (n); | |
1219 | fields = SCM_EOL; | |
1220 | { | |
1221 | size_t m = exp_nfields[n]; | |
1222 | while (m--) | |
1223 | fields = scm_cons (scm_from_locale_symbol (exp_field_names[n][m]), fields); | |
1224 | } | |
1225 | ||
1226 | return scm_c_make_struct (scm_exp_vtable_vtable, 0, 5, | |
1227 | SCM_UNPACK (layout), SCM_UNPACK (printer), SCM_UNPACK (name), | |
1228 | SCM_UNPACK (code), SCM_UNPACK (fields)); | |
1229 | } | |
1230 | ||
1231 | void | |
1232 | scm_init_expand () | |
1233 | { | |
1234 | size_t n; | |
1235 | SCM exp_vtable_list = SCM_EOL; | |
1236 | ||
1237 | DEFINE_NAMES (VOID); | |
1238 | DEFINE_NAMES (CONST); | |
1239 | DEFINE_NAMES (PRIMITIVE_REF); | |
1240 | DEFINE_NAMES (LEXICAL_REF); | |
1241 | DEFINE_NAMES (LEXICAL_SET); | |
1242 | DEFINE_NAMES (MODULE_REF); | |
1243 | DEFINE_NAMES (MODULE_SET); | |
1244 | DEFINE_NAMES (TOPLEVEL_REF); | |
1245 | DEFINE_NAMES (TOPLEVEL_SET); | |
1246 | DEFINE_NAMES (TOPLEVEL_DEFINE); | |
1247 | DEFINE_NAMES (CONDITIONAL); | |
7081d4f9 | 1248 | DEFINE_NAMES (CALL); |
a881a4ae | 1249 | DEFINE_NAMES (PRIMCALL); |
6fc3eae4 | 1250 | DEFINE_NAMES (SEQ); |
dc3e203e AW |
1251 | DEFINE_NAMES (LAMBDA); |
1252 | DEFINE_NAMES (LAMBDA_CASE); | |
1253 | DEFINE_NAMES (LET); | |
1254 | DEFINE_NAMES (LETREC); | |
1255 | DEFINE_NAMES (DYNLET); | |
1256 | ||
1257 | scm_exp_vtable_vtable = | |
1258 | scm_make_vtable (scm_from_locale_string (SCM_VTABLE_BASE_LAYOUT "pwuwpw"), | |
1259 | SCM_BOOL_F); | |
1260 | ||
1261 | for (n = 0; n < SCM_NUM_EXPANDED_TYPES; n++) | |
1262 | exp_vtables[n] = make_exp_vtable (n); | |
1263 | ||
1264 | /* Now walk back down, consing in reverse. */ | |
1265 | while (n--) | |
1266 | exp_vtable_list = scm_cons (exp_vtables[n], exp_vtable_list); | |
1267 | ||
ccbc25f3 | 1268 | scm_c_define ("%expanded-vtables", scm_vector (exp_vtable_list)); |
dc3e203e AW |
1269 | |
1270 | #include "libguile/expand.x" | |
1271 | } | |
1272 | ||
1273 | /* | |
1274 | Local Variables: | |
1275 | c-file-style: "gnu" | |
1276 | End: | |
1277 | */ |