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ee6aac97 MD |
1 | /* srfi-1.c --- SRFI-1 procedures for Guile |
2 | * | |
cf9d3c47 KR |
3 | * Copyright (C) 1995, 1996, 1997, 2000, 2001, 2002, 2003, 2005, 2006 |
4 | * Free Software Foundation, Inc. | |
5 | * | |
73be1d9e MV |
6 | * This library is free software; you can redistribute it and/or |
7 | * modify it under the terms of the GNU Lesser General Public | |
8 | * License as published by the Free Software Foundation; either | |
9 | * version 2.1 of the License, or (at your option) any later version. | |
ee6aac97 | 10 | * |
73be1d9e MV |
11 | * This library is distributed in the hope that it will be useful, |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
14 | * Lesser General Public License for more details. | |
ee6aac97 | 15 | * |
73be1d9e MV |
16 | * You should have received a copy of the GNU Lesser General Public |
17 | * License along with this library; if not, write to the Free Software | |
92205699 | 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
73be1d9e | 19 | */ |
ee6aac97 MD |
20 | |
21 | #include <libguile.h> | |
22 | #include <libguile/lang.h> | |
23 | ||
24 | #include "srfi-1.h" | |
25 | ||
26 | /* The intent of this file is to gradually replace those Scheme | |
27 | * procedures in srfi-1.scm which extends core primitive procedures, | |
28 | * so that using srfi-1 won't have performance penalties. | |
29 | * | |
30 | * Please feel free to contribute any new replacements! | |
31 | */ | |
32 | ||
33 | static long | |
34 | srfi1_ilength (SCM sx) | |
35 | { | |
36 | long i = 0; | |
37 | SCM tortoise = sx; | |
38 | SCM hare = sx; | |
39 | ||
40 | do { | |
41 | if (SCM_NULL_OR_NIL_P(hare)) return i; | |
896df2d5 | 42 | if (!scm_is_pair (hare)) return -2; |
ee6aac97 MD |
43 | hare = SCM_CDR(hare); |
44 | i++; | |
45 | if (SCM_NULL_OR_NIL_P(hare)) return i; | |
896df2d5 | 46 | if (!scm_is_pair (hare)) return -2; |
ee6aac97 MD |
47 | hare = SCM_CDR(hare); |
48 | i++; | |
49 | /* For every two steps the hare takes, the tortoise takes one. */ | |
50 | tortoise = SCM_CDR(tortoise); | |
51 | } | |
bc36d050 | 52 | while (! scm_is_eq (hare, tortoise)); |
ee6aac97 MD |
53 | |
54 | /* If the tortoise ever catches the hare, then the list must contain | |
55 | a cycle. */ | |
56 | return -1; | |
57 | } | |
58 | ||
d0a634de KR |
59 | static SCM |
60 | equal_trampoline (SCM proc, SCM arg1, SCM arg2) | |
61 | { | |
62 | return scm_equal_p (arg1, arg2); | |
63 | } | |
64 | ||
cf9d3c47 KR |
65 | /* list_copy_part() copies the first COUNT cells of LST, puts the result at |
66 | *dst, and returns the SCM_CDRLOC of the last cell in that new list. | |
67 | ||
68 | This function is designed to be careful about LST possibly having changed | |
69 | in between the caller deciding what to copy, and the copy actually being | |
70 | done here. The COUNT ensures we terminate if LST has become circular, | |
71 | SCM_VALIDATE_CONS guards against a cdr in the list changed to some | |
72 | non-pair object. */ | |
73 | ||
74 | #include <stdio.h> | |
75 | static SCM * | |
76 | list_copy_part (SCM lst, int count, SCM *dst) | |
77 | #define FUNC_NAME "list_copy_part" | |
78 | { | |
79 | SCM c; | |
80 | for ( ; count > 0; count--) | |
81 | { | |
82 | SCM_VALIDATE_CONS (SCM_ARGn, lst); | |
83 | c = scm_cons (SCM_CAR (lst), SCM_EOL); | |
84 | *dst = c; | |
85 | dst = SCM_CDRLOC (c); | |
86 | lst = SCM_CDR (lst); | |
87 | } | |
88 | return dst; | |
89 | } | |
90 | #undef FUNC_NAME | |
91 | ||
d0a634de | 92 | |
b1fff4e7 KR |
93 | SCM_DEFINE (scm_srfi1_alist_copy, "alist-copy", 1, 0, 0, |
94 | (SCM alist), | |
95 | "Return a copy of @var{alist}, copying both the pairs comprising\n" | |
96 | "the list and those making the associations.") | |
97 | #define FUNC_NAME s_scm_srfi1_alist_copy | |
98 | { | |
99 | SCM ret, *p, elem, c; | |
100 | ||
101 | /* ret is the list to return. p is where to append to it, initially &ret | |
102 | then SCM_CDRLOC of the last pair. */ | |
103 | ret = SCM_EOL; | |
104 | p = &ret; | |
105 | ||
106 | for ( ; scm_is_pair (alist); alist = SCM_CDR (alist)) | |
107 | { | |
108 | elem = SCM_CAR (alist); | |
109 | ||
110 | /* each element of alist must be a pair */ | |
111 | SCM_ASSERT_TYPE (scm_is_pair (elem), alist, SCM_ARG1, FUNC_NAME, | |
112 | "association list"); | |
113 | ||
114 | c = scm_cons (scm_cons (SCM_CAR (elem), SCM_CDR (elem)), SCM_EOL); | |
115 | *p = c; | |
116 | p = SCM_CDRLOC (c); | |
117 | } | |
118 | ||
119 | /* alist must be a proper list */ | |
120 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (alist), alist, SCM_ARG1, FUNC_NAME, | |
121 | "association list"); | |
122 | return ret; | |
123 | } | |
124 | #undef FUNC_NAME | |
125 | ||
126 | ||
9a993171 KR |
127 | |
128 | SCM_DEFINE (scm_srfi1_append_reverse, "append-reverse", 2, 0, 0, | |
129 | (SCM revhead, SCM tail), | |
130 | "Reverse @var{rev-head}, append @var{tail} to it, and return the\n" | |
131 | "result. This is equivalent to @code{(append (reverse\n" | |
132 | "@var{rev-head}) @var{tail})}, but its implementation is more\n" | |
133 | "efficient.\n" | |
134 | "\n" | |
135 | "@example\n" | |
136 | "(append-reverse '(1 2 3) '(4 5 6)) @result{} (3 2 1 4 5 6)\n" | |
137 | "@end example") | |
138 | #define FUNC_NAME s_scm_srfi1_append_reverse | |
139 | { | |
140 | while (scm_is_pair (revhead)) | |
141 | { | |
142 | /* copy first element of revhead onto front of tail */ | |
143 | tail = scm_cons (SCM_CAR (revhead), tail); | |
144 | revhead = SCM_CDR (revhead); | |
145 | } | |
146 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (revhead), revhead, SCM_ARG1, FUNC_NAME, | |
147 | "list"); | |
148 | return tail; | |
149 | } | |
150 | #undef FUNC_NAME | |
151 | ||
152 | ||
153 | SCM_DEFINE (scm_srfi1_append_reverse_x, "append-reverse!", 2, 0, 0, | |
154 | (SCM revhead, SCM tail), | |
155 | "Reverse @var{rev-head}, append @var{tail} to it, and return the\n" | |
156 | "result. This is equivalent to @code{(append! (reverse!\n" | |
157 | "@var{rev-head}) @var{tail})}, but its implementation is more\n" | |
158 | "efficient.\n" | |
159 | "\n" | |
160 | "@example\n" | |
161 | "(append-reverse! (list 1 2 3) '(4 5 6)) @result{} (3 2 1 4 5 6)\n" | |
162 | "@end example\n" | |
163 | "\n" | |
164 | "@var{rev-head} may be modified in order to produce the result.") | |
165 | #define FUNC_NAME s_scm_srfi1_append_reverse_x | |
166 | { | |
167 | SCM newtail; | |
168 | ||
169 | while (scm_is_pair (revhead)) | |
170 | { | |
171 | /* take the first cons cell from revhead */ | |
172 | newtail = revhead; | |
173 | revhead = SCM_CDR (revhead); | |
174 | ||
175 | /* make it the new start of tail, appending the previous */ | |
176 | SCM_SETCDR (newtail, tail); | |
177 | tail = newtail; | |
178 | } | |
179 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (revhead), revhead, SCM_ARG1, FUNC_NAME, | |
180 | "list"); | |
181 | return tail; | |
182 | } | |
183 | #undef FUNC_NAME | |
184 | ||
185 | ||
6e9f3c26 KR |
186 | SCM_DEFINE (scm_srfi1_break, "break", 2, 0, 0, |
187 | (SCM pred, SCM lst), | |
188 | "Return two values, the longest initial prefix of @var{lst}\n" | |
189 | "whose elements all fail the predicate @var{pred}, and the\n" | |
190 | "remainder of @var{lst}.\n" | |
191 | "\n" | |
192 | "Note that the name @code{break} conflicts with the @code{break}\n" | |
193 | "binding established by @code{while}. Applications wanting to\n" | |
194 | "use @code{break} from within a @code{while} loop will need to\n" | |
195 | "make a new define under a different name.") | |
196 | #define FUNC_NAME s_scm_srfi1_break | |
197 | { | |
198 | scm_t_trampoline_1 pred_tramp; | |
199 | SCM ret, *p; | |
200 | ||
201 | pred_tramp = scm_trampoline_1 (pred); | |
202 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
203 | ||
204 | ret = SCM_EOL; | |
205 | p = &ret; | |
206 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) | |
207 | { | |
208 | SCM elem = SCM_CAR (lst); | |
209 | if (scm_is_true (pred_tramp (pred, elem))) | |
210 | goto done; | |
211 | ||
212 | /* want this elem, tack it onto the end of ret */ | |
213 | *p = scm_cons (elem, SCM_EOL); | |
214 | p = SCM_CDRLOC (*p); | |
215 | } | |
216 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG2, FUNC_NAME, "list"); | |
217 | ||
218 | done: | |
219 | return scm_values (scm_list_2 (ret, lst)); | |
220 | } | |
221 | #undef FUNC_NAME | |
222 | ||
223 | ||
224 | SCM_DEFINE (scm_srfi1_break_x, "break!", 2, 0, 0, | |
225 | (SCM pred, SCM lst), | |
226 | "Return two values, the longest initial prefix of @var{lst}\n" | |
227 | "whose elements all fail the predicate @var{pred}, and the\n" | |
228 | "remainder of @var{lst}. @var{lst} may be modified to form the\n" | |
229 | "return.") | |
230 | #define FUNC_NAME s_scm_srfi1_break_x | |
231 | { | |
232 | SCM upto, *p; | |
233 | scm_t_trampoline_1 pred_tramp; | |
234 | ||
235 | pred_tramp = scm_trampoline_1 (pred); | |
236 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
237 | ||
238 | p = &lst; | |
239 | for (upto = lst; scm_is_pair (upto); upto = SCM_CDR (upto)) | |
240 | { | |
241 | if (scm_is_true (pred_tramp (pred, SCM_CAR (upto)))) | |
242 | goto done; | |
243 | ||
244 | /* want this element */ | |
245 | p = SCM_CDRLOC (upto); | |
246 | } | |
247 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (upto), lst, SCM_ARG2, FUNC_NAME, "list"); | |
248 | ||
249 | done: | |
250 | *p = SCM_EOL; | |
251 | return scm_values (scm_list_2 (lst, upto)); | |
252 | } | |
253 | #undef FUNC_NAME | |
254 | ||
255 | ||
e556f8c3 KR |
256 | SCM_DEFINE (scm_srfi1_car_plus_cdr, "car+cdr", 1, 0, 0, |
257 | (SCM pair), | |
258 | "Return two values, the @sc{car} and the @sc{cdr} of @var{pair}.") | |
259 | #define FUNC_NAME s_scm_srfi1_car_plus_cdr | |
260 | { | |
261 | SCM_VALIDATE_CONS (SCM_ARG1, pair); | |
262 | return scm_values (scm_list_2 (SCM_CAR (pair), SCM_CDR (pair))); | |
263 | } | |
264 | #undef FUNC_NAME | |
265 | ||
266 | ||
c66c6d53 KR |
267 | SCM_DEFINE (scm_srfi1_concatenate, "concatenate", 1, 0, 0, |
268 | (SCM lstlst), | |
269 | "Construct a list by appending all lists in @var{lstlst}.\n" | |
270 | "\n" | |
271 | "@code{concatenate} is the same as @code{(apply append\n" | |
272 | "@var{lstlst})}. It exists because some Scheme implementations\n" | |
273 | "have a limit on the number of arguments a function takes, which\n" | |
274 | "the @code{apply} might exceed. In Guile there is no such\n" | |
275 | "limit.") | |
276 | #define FUNC_NAME s_scm_srfi1_concatenate | |
277 | { | |
278 | SCM_VALIDATE_LIST (SCM_ARG1, lstlst); | |
279 | return scm_append (lstlst); | |
280 | } | |
281 | #undef FUNC_NAME | |
282 | ||
47f2726f | 283 | |
c66c6d53 KR |
284 | SCM_DEFINE (scm_srfi1_concatenate_x, "concatenate!", 1, 0, 0, |
285 | (SCM lstlst), | |
286 | "Construct a list by appending all lists in @var{lstlst}. Those\n" | |
287 | "lists may be modified to produce the result.\n" | |
288 | "\n" | |
289 | "@code{concatenate!} is the same as @code{(apply append!\n" | |
290 | "@var{lstlst})}. It exists because some Scheme implementations\n" | |
291 | "have a limit on the number of arguments a function takes, which\n" | |
292 | "the @code{apply} might exceed. In Guile there is no such\n" | |
293 | "limit.") | |
294 | #define FUNC_NAME s_scm_srfi1_concatenate | |
295 | { | |
296 | SCM_VALIDATE_LIST (SCM_ARG1, lstlst); | |
297 | return scm_append_x (lstlst); | |
298 | } | |
299 | #undef FUNC_NAME | |
47f2726f KR |
300 | |
301 | ||
110348ae | 302 | SCM_DEFINE (scm_srfi1_count, "count", 2, 0, 1, |
edea856c | 303 | (SCM pred, SCM list1, SCM rest), |
110348ae KR |
304 | "Return a count of the number of times @var{pred} returns true\n" |
305 | "when called on elements from the given lists.\n" | |
306 | "\n" | |
307 | "@var{pred} is called with @var{N} parameters @code{(@var{pred}\n" | |
308 | "@var{elem1} @dots{} @var{elemN})}, each element being from the\n" | |
edea856c | 309 | "corresponding @var{list1} @dots{} @var{lstN}. The first call is\n" |
110348ae KR |
310 | "with the first element of each list, the second with the second\n" |
311 | "element from each, and so on.\n" | |
312 | "\n" | |
313 | "Counting stops when the end of the shortest list is reached.\n" | |
314 | "At least one list must be non-circular.") | |
315 | #define FUNC_NAME s_scm_srfi1_count | |
316 | { | |
317 | long count; | |
5fc743b4 KR |
318 | SCM lst; |
319 | int argnum; | |
110348ae KR |
320 | SCM_VALIDATE_REST_ARGUMENT (rest); |
321 | ||
322 | count = 0; | |
323 | ||
896df2d5 | 324 | if (scm_is_null (rest)) |
110348ae KR |
325 | { |
326 | /* one list */ | |
327 | scm_t_trampoline_1 pred_tramp; | |
328 | pred_tramp = scm_trampoline_1 (pred); | |
329 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
330 | ||
896df2d5 | 331 | for ( ; scm_is_pair (list1); list1 = SCM_CDR (list1)) |
edea856c | 332 | count += scm_is_true (pred_tramp (pred, SCM_CAR (list1))); |
110348ae | 333 | |
5fc743b4 KR |
334 | /* check below that list1 is a proper list, and done */ |
335 | end_list1: | |
336 | lst = list1; | |
337 | argnum = 2; | |
110348ae | 338 | } |
896df2d5 | 339 | else if (scm_is_pair (rest) && scm_is_null (SCM_CDR (rest))) |
110348ae KR |
340 | { |
341 | /* two lists */ | |
342 | scm_t_trampoline_2 pred_tramp; | |
edea856c | 343 | SCM list2; |
110348ae KR |
344 | |
345 | pred_tramp = scm_trampoline_2 (pred); | |
346 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
347 | ||
edea856c | 348 | list2 = SCM_CAR (rest); |
110348ae KR |
349 | for (;;) |
350 | { | |
896df2d5 | 351 | if (! scm_is_pair (list1)) |
5fc743b4 | 352 | goto end_list1; |
896df2d5 | 353 | if (! scm_is_pair (list2)) |
110348ae | 354 | { |
5fc743b4 KR |
355 | lst = list2; |
356 | argnum = 3; | |
110348ae KR |
357 | break; |
358 | } | |
00874d5f | 359 | count += scm_is_true (pred_tramp |
edea856c SJ |
360 | (pred, SCM_CAR (list1), SCM_CAR (list2))); |
361 | list1 = SCM_CDR (list1); | |
362 | list2 = SCM_CDR (list2); | |
110348ae KR |
363 | } |
364 | } | |
365 | else | |
366 | { | |
367 | /* three or more lists */ | |
eccd308a KR |
368 | SCM vec, args, a; |
369 | size_t len, i; | |
110348ae | 370 | |
eccd308a KR |
371 | /* vec is the list arguments */ |
372 | vec = scm_vector (scm_cons (list1, rest)); | |
373 | len = SCM_SIMPLE_VECTOR_LENGTH (vec); | |
110348ae | 374 | |
eccd308a | 375 | /* args is the argument list to pass to pred, same length as vec, |
110348ae | 376 | re-used for each call */ |
eccd308a | 377 | args = scm_make_list (SCM_I_MAKINUM (len), SCM_UNDEFINED); |
110348ae KR |
378 | |
379 | for (;;) | |
380 | { | |
eccd308a KR |
381 | /* first elem of each list in vec into args, and step those |
382 | vec entries onto their next element */ | |
383 | for (i = 0, a = args, argnum = 2; | |
384 | i < len; | |
385 | i++, a = SCM_CDR (a), argnum++) | |
110348ae | 386 | { |
eccd308a | 387 | lst = SCM_SIMPLE_VECTOR_REF (vec, i); /* list argument */ |
896df2d5 | 388 | if (! scm_is_pair (lst)) |
5fc743b4 | 389 | goto check_lst_and_done; |
110348ae | 390 | SCM_SETCAR (a, SCM_CAR (lst)); /* arg for pred */ |
eccd308a | 391 | SCM_SIMPLE_VECTOR_SET (vec, i, SCM_CDR (lst)); /* rest of lst */ |
110348ae KR |
392 | } |
393 | ||
00874d5f | 394 | count += scm_is_true (scm_apply (pred, args, SCM_EOL)); |
110348ae KR |
395 | } |
396 | } | |
5fc743b4 KR |
397 | |
398 | check_lst_and_done: | |
399 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, argnum, FUNC_NAME, "list"); | |
93ccaef0 | 400 | return scm_from_long (count); |
110348ae KR |
401 | } |
402 | #undef FUNC_NAME | |
403 | ||
404 | ||
d0a634de KR |
405 | SCM_DEFINE (scm_srfi1_delete, "delete", 2, 1, 0, |
406 | (SCM x, SCM lst, SCM pred), | |
407 | "Return a list containing the elements of @var{lst} but with\n" | |
408 | "those equal to @var{x} deleted. The returned elements will be\n" | |
409 | "in the same order as they were in @var{lst}.\n" | |
410 | "\n" | |
411 | "Equality is determined by @var{pred}, or @code{equal?} if not\n" | |
412 | "given. An equality call is made just once for each element,\n" | |
413 | "but the order in which the calls are made on the elements is\n" | |
414 | "unspecified.\n" | |
415 | "\n" | |
416 | "The equality calls are always @code{(pred x elem)}, ie.@: the\n" | |
417 | "given @var{x} is first. This means for instance elements\n" | |
418 | "greater than 5 can be deleted with @code{(delete 5 lst <)}.\n" | |
419 | "\n" | |
420 | "@var{lst} is not modified, but the returned list might share a\n" | |
421 | "common tail with @var{lst}.") | |
422 | #define FUNC_NAME s_scm_srfi1_delete | |
423 | { | |
424 | scm_t_trampoline_2 equal_p; | |
425 | SCM ret, *p, keeplst; | |
cf9d3c47 | 426 | int count; |
d0a634de KR |
427 | |
428 | if (SCM_UNBNDP (pred)) | |
429 | return scm_delete (x, lst); | |
430 | ||
431 | equal_p = scm_trampoline_2 (pred); | |
432 | SCM_ASSERT (equal_p, pred, SCM_ARG3, FUNC_NAME); | |
433 | ||
434 | /* ret is the return list being constructed. p is where to append to it, | |
435 | initially &ret then SCM_CDRLOC of the last pair. lst progresses as | |
436 | elements are considered. | |
437 | ||
438 | Elements to be retained are not immediately copied, instead keeplst is | |
cf9d3c47 KR |
439 | the last pair in lst which is to be retained but not yet copied, count |
440 | is how many from there are wanted. When there's no more deletions, *p | |
441 | can be set to keeplst to share the remainder of the original lst. (The | |
442 | entire original lst if there's no deletions at all.) */ | |
d0a634de KR |
443 | |
444 | keeplst = lst; | |
cf9d3c47 | 445 | count = 0; |
d0a634de KR |
446 | p = &ret; |
447 | ||
896df2d5 | 448 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) |
d0a634de | 449 | { |
00874d5f | 450 | if (scm_is_true (equal_p (pred, x, SCM_CAR (lst)))) |
d0a634de | 451 | { |
cf9d3c47 KR |
452 | /* delete this element, so copy those at keeplst */ |
453 | p = list_copy_part (keeplst, count, p); | |
d0a634de | 454 | keeplst = SCM_CDR (lst); |
cf9d3c47 KR |
455 | count = 0; |
456 | } | |
457 | else | |
458 | { | |
459 | /* keep this element */ | |
460 | count++; | |
d0a634de KR |
461 | } |
462 | } | |
463 | ||
464 | /* final retained elements */ | |
465 | *p = keeplst; | |
466 | ||
467 | /* demand that lst was a proper list */ | |
468 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG2, FUNC_NAME, "list"); | |
469 | ||
470 | return ret; | |
471 | } | |
472 | #undef FUNC_NAME | |
473 | ||
474 | ||
475 | SCM_DEFINE (scm_srfi1_delete_x, "delete!", 2, 1, 0, | |
476 | (SCM x, SCM lst, SCM pred), | |
477 | "Return a list containing the elements of @var{lst} but with\n" | |
478 | "those equal to @var{x} deleted. The returned elements will be\n" | |
479 | "in the same order as they were in @var{lst}.\n" | |
480 | "\n" | |
481 | "Equality is determined by @var{pred}, or @code{equal?} if not\n" | |
482 | "given. An equality call is made just once for each element,\n" | |
483 | "but the order in which the calls are made on the elements is\n" | |
484 | "unspecified.\n" | |
485 | "\n" | |
486 | "The equality calls are always @code{(pred x elem)}, ie.@: the\n" | |
487 | "given @var{x} is first. This means for instance elements\n" | |
488 | "greater than 5 can be deleted with @code{(delete 5 lst <)}.\n" | |
489 | "\n" | |
490 | "@var{lst} may be modified to construct the returned list.") | |
491 | #define FUNC_NAME s_scm_srfi1_delete_x | |
492 | { | |
493 | scm_t_trampoline_2 equal_p; | |
494 | SCM walk; | |
495 | SCM *prev; | |
496 | ||
497 | if (SCM_UNBNDP (pred)) | |
498 | return scm_delete_x (x, lst); | |
499 | ||
500 | equal_p = scm_trampoline_2 (pred); | |
501 | SCM_ASSERT (equal_p, pred, SCM_ARG3, FUNC_NAME); | |
502 | ||
503 | for (prev = &lst, walk = lst; | |
896df2d5 | 504 | scm_is_pair (walk); |
d0a634de KR |
505 | walk = SCM_CDR (walk)) |
506 | { | |
00874d5f | 507 | if (scm_is_true (equal_p (pred, x, SCM_CAR (walk)))) |
d0a634de KR |
508 | *prev = SCM_CDR (walk); |
509 | else | |
510 | prev = SCM_CDRLOC (walk); | |
511 | } | |
512 | ||
513 | /* demand the input was a proper list */ | |
514 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (walk), walk, SCM_ARG2, FUNC_NAME,"list"); | |
515 | return lst; | |
516 | } | |
517 | #undef FUNC_NAME | |
518 | ||
519 | ||
520 | SCM_DEFINE (scm_srfi1_delete_duplicates, "delete-duplicates", 1, 1, 0, | |
521 | (SCM lst, SCM pred), | |
522 | "Return a list containing the elements of @var{lst} but without\n" | |
523 | "duplicates.\n" | |
524 | "\n" | |
525 | "When elements are equal, only the first in @var{lst} is\n" | |
526 | "retained. Equal elements can be anywhere in @var{lst}, they\n" | |
527 | "don't have to be adjacent. The returned list will have the\n" | |
528 | "retained elements in the same order as they were in @var{lst}.\n" | |
529 | "\n" | |
530 | "Equality is determined by @var{pred}, or @code{equal?} if not\n" | |
531 | "given. Calls @code{(pred x y)} are made with element @var{x}\n" | |
532 | "being before @var{y} in @var{lst}. A call is made at most once\n" | |
533 | "for each combination, but the sequence of the calls across the\n" | |
534 | "elements is unspecified.\n" | |
535 | "\n" | |
536 | "@var{lst} is not modified, but the return might share a common\n" | |
537 | "tail with @var{lst}.\n" | |
538 | "\n" | |
539 | "In the worst case, this is an @math{O(N^2)} algorithm because\n" | |
540 | "it must check each element against all those preceding it. For\n" | |
541 | "long lists it is more efficient to sort and then compare only\n" | |
542 | "adjacent elements.") | |
543 | #define FUNC_NAME s_scm_srfi1_delete_duplicates | |
544 | { | |
545 | scm_t_trampoline_2 equal_p; | |
546 | SCM ret, *p, keeplst, item, l; | |
cf9d3c47 | 547 | int count, i; |
d0a634de KR |
548 | |
549 | /* ret is the new list constructed. p is where to append, initially &ret | |
550 | then SCM_CDRLOC of the last pair. lst is advanced as each element is | |
551 | considered. | |
552 | ||
553 | Elements retained are not immediately appended to ret, instead keeplst | |
554 | is the last pair in lst which is to be kept but is not yet copied. | |
555 | Initially this is the first pair of lst, since the first element is | |
556 | always retained. | |
557 | ||
558 | *p is kept set to keeplst, so ret (inclusive) to lst (exclusive) is all | |
559 | the elements retained, making the equality search loop easy. | |
560 | ||
561 | If an item must be deleted, elements from keeplst (inclusive) to lst | |
562 | (exclusive) must be copied and appended to ret. When there's no more | |
563 | deletions, *p is left set to keeplst, so ret shares structure with the | |
564 | original lst. (ret will be the entire original lst if there are no | |
565 | deletions.) */ | |
566 | ||
567 | /* skip to end if an empty list (or something invalid) */ | |
cf9d3c47 KR |
568 | ret = SCM_EOL; |
569 | ||
570 | if (SCM_UNBNDP (pred)) | |
571 | equal_p = equal_trampoline; | |
572 | else | |
d0a634de | 573 | { |
cf9d3c47 KR |
574 | equal_p = scm_trampoline_2 (pred); |
575 | SCM_ASSERT (equal_p, pred, SCM_ARG2, FUNC_NAME); | |
576 | } | |
d0a634de | 577 | |
cf9d3c47 KR |
578 | keeplst = lst; |
579 | count = 0; | |
580 | p = &ret; | |
d0a634de | 581 | |
cf9d3c47 KR |
582 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) |
583 | { | |
584 | item = SCM_CAR (lst); | |
d0a634de | 585 | |
cf9d3c47 KR |
586 | /* look for item in "ret" list */ |
587 | for (l = ret; scm_is_pair (l); l = SCM_CDR (l)) | |
588 | { | |
589 | if (scm_is_true (equal_p (pred, SCM_CAR (l), item))) | |
d0a634de | 590 | { |
cf9d3c47 KR |
591 | /* "item" is a duplicate, so copy keeplst onto ret */ |
592 | duplicate: | |
593 | p = list_copy_part (keeplst, count, p); | |
594 | ||
595 | keeplst = SCM_CDR (lst); /* elem after the one deleted */ | |
596 | count = 0; | |
597 | goto next_elem; | |
d0a634de KR |
598 | } |
599 | } | |
d0a634de | 600 | |
cf9d3c47 KR |
601 | /* look for item in "keeplst" list |
602 | be careful traversing, in case nasty code changed the cdrs */ | |
603 | for (i = 0, l = keeplst; | |
604 | i < count && scm_is_pair (l); | |
605 | i++, l = SCM_CDR (l)) | |
606 | if (scm_is_true (equal_p (pred, SCM_CAR (l), item))) | |
607 | goto duplicate; | |
608 | ||
609 | /* keep this element */ | |
610 | count++; | |
611 | ||
612 | next_elem: | |
613 | ; | |
614 | } | |
d0a634de KR |
615 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG1, FUNC_NAME, "list"); |
616 | ||
cf9d3c47 KR |
617 | /* share tail of keeplst items */ |
618 | *p = keeplst; | |
619 | ||
d0a634de KR |
620 | return ret; |
621 | } | |
622 | #undef FUNC_NAME | |
623 | ||
624 | ||
625 | SCM_DEFINE (scm_srfi1_delete_duplicates_x, "delete-duplicates!", 1, 1, 0, | |
626 | (SCM lst, SCM pred), | |
627 | "Return a list containing the elements of @var{lst} but without\n" | |
628 | "duplicates.\n" | |
629 | "\n" | |
630 | "When elements are equal, only the first in @var{lst} is\n" | |
631 | "retained. Equal elements can be anywhere in @var{lst}, they\n" | |
632 | "don't have to be adjacent. The returned list will have the\n" | |
633 | "retained elements in the same order as they were in @var{lst}.\n" | |
634 | "\n" | |
635 | "Equality is determined by @var{pred}, or @code{equal?} if not\n" | |
636 | "given. Calls @code{(pred x y)} are made with element @var{x}\n" | |
637 | "being before @var{y} in @var{lst}. A call is made at most once\n" | |
638 | "for each combination, but the sequence of the calls across the\n" | |
639 | "elements is unspecified.\n" | |
640 | "\n" | |
641 | "@var{lst} may be modified to construct the returned list.\n" | |
642 | "\n" | |
643 | "In the worst case, this is an @math{O(N^2)} algorithm because\n" | |
644 | "it must check each element against all those preceding it. For\n" | |
645 | "long lists it is more efficient to sort and then compare only\n" | |
646 | "adjacent elements.") | |
647 | #define FUNC_NAME s_scm_srfi1_delete_duplicates_x | |
648 | { | |
649 | scm_t_trampoline_2 equal_p; | |
650 | SCM ret, endret, item, l; | |
651 | ||
652 | /* ret is the return list, constructed from the pairs in lst. endret is | |
653 | the last pair of ret, initially the first pair. lst is advanced as | |
654 | elements are considered. */ | |
655 | ||
656 | /* skip to end if an empty list (or something invalid) */ | |
657 | ret = lst; | |
896df2d5 | 658 | if (scm_is_pair (lst)) |
d0a634de KR |
659 | { |
660 | if (SCM_UNBNDP (pred)) | |
661 | equal_p = equal_trampoline; | |
662 | else | |
663 | { | |
664 | equal_p = scm_trampoline_2 (pred); | |
665 | SCM_ASSERT (equal_p, pred, SCM_ARG2, FUNC_NAME); | |
666 | } | |
667 | ||
668 | endret = ret; | |
669 | ||
670 | /* loop over lst elements starting from second */ | |
671 | for (;;) | |
672 | { | |
673 | lst = SCM_CDR (lst); | |
896df2d5 | 674 | if (! scm_is_pair (lst)) |
d0a634de KR |
675 | break; |
676 | item = SCM_CAR (lst); | |
677 | ||
678 | /* is item equal to any element from ret to endret (inclusive)? */ | |
679 | l = ret; | |
680 | for (;;) | |
681 | { | |
00874d5f | 682 | if (scm_is_true (equal_p (pred, SCM_CAR (l), item))) |
d0a634de KR |
683 | break; /* equal, forget this element */ |
684 | ||
bc36d050 | 685 | if (scm_is_eq (l, endret)) |
d0a634de KR |
686 | { |
687 | /* not equal to any, so append this pair */ | |
688 | SCM_SETCDR (endret, lst); | |
689 | endret = lst; | |
690 | break; | |
691 | } | |
692 | l = SCM_CDR (l); | |
693 | } | |
694 | } | |
695 | ||
696 | /* terminate, in case last element was deleted */ | |
697 | SCM_SETCDR (endret, SCM_EOL); | |
698 | } | |
699 | ||
700 | /* demand that lst was a proper list */ | |
701 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG1, FUNC_NAME, "list"); | |
702 | ||
703 | return ret; | |
704 | } | |
705 | #undef FUNC_NAME | |
706 | ||
707 | ||
2b077051 KR |
708 | SCM_DEFINE (scm_srfi1_drop_right, "drop-right", 2, 0, 0, |
709 | (SCM lst, SCM n), | |
710 | "Return a new list containing all except the last @var{n}\n" | |
711 | "elements of @var{lst}.") | |
712 | #define FUNC_NAME s_scm_srfi1_drop_right | |
713 | { | |
714 | SCM tail = scm_list_tail (lst, n); | |
715 | SCM ret = SCM_EOL; | |
716 | SCM *rend = &ret; | |
717 | while (scm_is_pair (tail)) | |
718 | { | |
719 | *rend = scm_cons (SCM_CAR (lst), SCM_EOL); | |
720 | rend = SCM_CDRLOC (*rend); | |
721 | ||
722 | lst = SCM_CDR (lst); | |
723 | tail = SCM_CDR (tail); | |
724 | } | |
725 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P(tail), tail, SCM_ARG1, FUNC_NAME, "list"); | |
726 | return ret; | |
727 | } | |
728 | #undef FUNC_NAME | |
c1635946 KR |
729 | |
730 | ||
597dbd4e KR |
731 | SCM_DEFINE (scm_srfi1_drop_right_x, "drop-right!", 2, 0, 0, |
732 | (SCM lst, SCM n), | |
733 | "Return the a list containing the @var{n} last elements of\n" | |
734 | "@var{lst}. @var{lst} may be modified to build the return.") | |
735 | #define FUNC_NAME s_scm_srfi1_drop_right_x | |
736 | { | |
737 | SCM tail, *p; | |
738 | ||
739 | if (scm_is_eq (n, SCM_INUM0)) | |
740 | return lst; | |
741 | ||
742 | tail = scm_list_tail (lst, n); | |
743 | p = &lst; | |
744 | ||
745 | /* p and tail work along the list, p being the cdrloc of the cell n steps | |
746 | behind tail */ | |
747 | for ( ; scm_is_pair (tail); tail = SCM_CDR (tail)) | |
748 | p = SCM_CDRLOC (*p); | |
749 | ||
750 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P(tail), tail, SCM_ARG1, FUNC_NAME, "list"); | |
751 | ||
752 | *p = SCM_EOL; | |
753 | return lst; | |
754 | } | |
755 | #undef FUNC_NAME | |
756 | ||
757 | ||
758 | SCM_DEFINE (scm_srfi1_drop_while, "drop-while", 2, 0, 0, | |
759 | (SCM pred, SCM lst), | |
760 | "Drop the longest initial prefix of @var{lst} whose elements all\n" | |
761 | "satisfy the predicate @var{pred}.") | |
762 | #define FUNC_NAME s_scm_srfi1_drop_while | |
763 | { | |
764 | scm_t_trampoline_1 pred_tramp = scm_trampoline_1 (pred); | |
765 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
766 | ||
767 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) | |
768 | if (scm_is_false (pred_tramp (pred, SCM_CAR (lst)))) | |
769 | goto done; | |
770 | ||
771 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG2, FUNC_NAME, "list"); | |
772 | done: | |
773 | return lst; | |
774 | } | |
775 | #undef FUNC_NAME | |
776 | ||
777 | ||
03731332 KR |
778 | SCM_DEFINE (scm_srfi1_eighth, "eighth", 1, 0, 0, |
779 | (SCM lst), | |
780 | "Return the eighth element of @var{lst}.") | |
781 | #define FUNC_NAME s_scm_srfi1_eighth | |
782 | { | |
783 | return scm_list_ref (lst, SCM_I_MAKINUM (7)); | |
784 | } | |
785 | #undef FUNC_NAME | |
786 | ||
787 | ||
788 | SCM_DEFINE (scm_srfi1_fifth, "fifth", 1, 0, 0, | |
789 | (SCM lst), | |
790 | "Return the fifth element of @var{lst}.") | |
791 | #define FUNC_NAME s_scm_srfi1_fifth | |
792 | { | |
793 | return scm_list_ref (lst, SCM_I_MAKINUM (4)); | |
794 | } | |
795 | #undef FUNC_NAME | |
796 | ||
797 | ||
c1635946 KR |
798 | SCM_DEFINE (scm_srfi1_filter_map, "filter-map", 2, 0, 1, |
799 | (SCM proc, SCM list1, SCM rest), | |
800 | "Apply @var{proc} to to the elements of @var{list1} @dots{} and\n" | |
801 | "return a list of the results as per SRFI-1 @code{map}, except\n" | |
802 | "that any @code{#f} results are omitted from the list returned.") | |
803 | #define FUNC_NAME s_scm_srfi1_filter_map | |
804 | { | |
805 | SCM ret, *loc, elem, newcell, lst; | |
806 | int argnum; | |
807 | ||
808 | SCM_VALIDATE_REST_ARGUMENT (rest); | |
809 | ||
810 | ret = SCM_EOL; | |
811 | loc = &ret; | |
812 | ||
3c55f6f1 | 813 | if (scm_is_null (rest)) |
c1635946 KR |
814 | { |
815 | /* one list */ | |
816 | scm_t_trampoline_1 proc_tramp = scm_trampoline_1 (proc); | |
817 | SCM_ASSERT (proc_tramp, proc, SCM_ARG1, FUNC_NAME); | |
818 | ||
819 | for ( ; scm_is_pair (list1); list1 = SCM_CDR (list1)) | |
820 | { | |
821 | elem = proc_tramp (proc, SCM_CAR (list1)); | |
822 | if (scm_is_true (elem)) | |
823 | { | |
824 | newcell = scm_cons (elem, SCM_EOL); | |
825 | *loc = newcell; | |
826 | loc = SCM_CDRLOC (newcell); | |
827 | } | |
828 | } | |
829 | ||
830 | /* check below that list1 is a proper list, and done */ | |
6507b831 | 831 | end_list1: |
c1635946 KR |
832 | lst = list1; |
833 | argnum = 2; | |
834 | } | |
3c55f6f1 | 835 | else if (scm_is_null (SCM_CDR (rest))) |
c1635946 KR |
836 | { |
837 | /* two lists */ | |
838 | scm_t_trampoline_2 proc_tramp = scm_trampoline_2 (proc); | |
839 | SCM list2 = SCM_CAR (rest); | |
840 | SCM_ASSERT (proc_tramp, proc, SCM_ARG1, FUNC_NAME); | |
841 | ||
842 | for (;;) | |
843 | { | |
844 | if (! scm_is_pair (list1)) | |
6507b831 | 845 | goto end_list1; |
c1635946 KR |
846 | if (! scm_is_pair (list2)) |
847 | { | |
848 | lst = list2; | |
849 | argnum = 3; | |
850 | goto check_lst_and_done; | |
851 | } | |
852 | elem = proc_tramp (proc, SCM_CAR (list1), SCM_CAR (list2)); | |
853 | if (scm_is_true (elem)) | |
854 | { | |
855 | newcell = scm_cons (elem, SCM_EOL); | |
856 | *loc = newcell; | |
857 | loc = SCM_CDRLOC (newcell); | |
858 | } | |
859 | list1 = SCM_CDR (list1); | |
860 | list2 = SCM_CDR (list2); | |
861 | } | |
862 | } | |
863 | else | |
864 | { | |
865 | /* three or more lists */ | |
eccd308a KR |
866 | SCM vec, args, a; |
867 | size_t len, i; | |
c1635946 | 868 | |
eccd308a KR |
869 | /* vec is the list arguments */ |
870 | vec = scm_vector (scm_cons (list1, rest)); | |
871 | len = SCM_SIMPLE_VECTOR_LENGTH (vec); | |
c1635946 | 872 | |
eccd308a | 873 | /* args is the argument list to pass to proc, same length as vec, |
c1635946 | 874 | re-used for each call */ |
eccd308a | 875 | args = scm_make_list (SCM_I_MAKINUM (len), SCM_UNDEFINED); |
c1635946 KR |
876 | |
877 | for (;;) | |
878 | { | |
eccd308a KR |
879 | /* first elem of each list in vec into args, and step those |
880 | vec entries onto their next element */ | |
881 | for (i = 0, a = args, argnum = 2; | |
882 | i < len; | |
883 | i++, a = SCM_CDR (a), argnum++) | |
c1635946 | 884 | { |
eccd308a | 885 | lst = SCM_SIMPLE_VECTOR_REF (vec, i); /* list argument */ |
c1635946 KR |
886 | if (! scm_is_pair (lst)) |
887 | goto check_lst_and_done; | |
888 | SCM_SETCAR (a, SCM_CAR (lst)); /* arg for proc */ | |
eccd308a | 889 | SCM_SIMPLE_VECTOR_SET (vec, i, SCM_CDR (lst)); /* rest of lst */ |
c1635946 KR |
890 | } |
891 | ||
892 | elem = scm_apply (proc, args, SCM_EOL); | |
893 | if (scm_is_true (elem)) | |
894 | { | |
895 | newcell = scm_cons (elem, SCM_EOL); | |
896 | *loc = newcell; | |
897 | loc = SCM_CDRLOC (newcell); | |
898 | } | |
899 | } | |
900 | } | |
901 | ||
902 | check_lst_and_done: | |
903 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, argnum, FUNC_NAME, "list"); | |
904 | return ret; | |
905 | } | |
906 | #undef FUNC_NAME | |
2b077051 KR |
907 | |
908 | ||
5df2ac97 KR |
909 | SCM_DEFINE (scm_srfi1_find, "find", 2, 0, 0, |
910 | (SCM pred, SCM lst), | |
911 | "Return the first element of @var{lst} which satisfies the\n" | |
912 | "predicate @var{pred}, or return @code{#f} if no such element is\n" | |
913 | "found.") | |
914 | #define FUNC_NAME s_scm_srfi1_find | |
915 | { | |
916 | scm_t_trampoline_1 pred_tramp = scm_trampoline_1 (pred); | |
917 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
918 | ||
919 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) | |
920 | { | |
921 | SCM elem = SCM_CAR (lst); | |
922 | if (scm_is_true (pred_tramp (pred, elem))) | |
923 | return elem; | |
924 | } | |
925 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG2, FUNC_NAME, "list"); | |
926 | ||
927 | return SCM_BOOL_F; | |
928 | } | |
929 | #undef FUNC_NAME | |
930 | ||
931 | ||
932 | SCM_DEFINE (scm_srfi1_find_tail, "find-tail", 2, 0, 0, | |
933 | (SCM pred, SCM lst), | |
934 | "Return the first pair of @var{lst} whose @sc{car} satisfies the\n" | |
935 | "predicate @var{pred}, or return @code{#f} if no such element is\n" | |
936 | "found.") | |
937 | #define FUNC_NAME s_scm_srfi1_find_tail | |
938 | { | |
939 | scm_t_trampoline_1 pred_tramp = scm_trampoline_1 (pred); | |
940 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
941 | ||
942 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) | |
943 | if (scm_is_true (pred_tramp (pred, SCM_CAR (lst)))) | |
944 | return lst; | |
945 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG2, FUNC_NAME, "list"); | |
946 | ||
947 | return SCM_BOOL_F; | |
948 | } | |
949 | #undef FUNC_NAME | |
950 | ||
951 | ||
e556f8c3 KR |
952 | SCM_DEFINE (scm_srfi1_fold, "fold", 3, 0, 1, |
953 | (SCM proc, SCM init, SCM list1, SCM rest), | |
954 | "Apply @var{proc} to the elements of @var{lst1} @dots{}\n" | |
955 | "@var{lstN} to build a result, and return that result.\n" | |
956 | "\n" | |
957 | "Each @var{proc} call is @code{(@var{proc} @var{elem1} @dots{}\n" | |
958 | "@var{elemN} @var{previous})}, where @var{elem1} is from\n" | |
959 | "@var{lst1}, through @var{elemN} from @var{lstN}.\n" | |
960 | "@var{previous} is the return from the previous call to\n" | |
961 | "@var{proc}, or the given @var{init} for the first call. If any\n" | |
962 | "list is empty, just @var{init} is returned.\n" | |
963 | "\n" | |
964 | "@code{fold} works through the list elements from first to last.\n" | |
965 | "The following shows a list reversal and the calls it makes,\n" | |
966 | "\n" | |
967 | "@example\n" | |
968 | "(fold cons '() '(1 2 3))\n" | |
969 | "\n" | |
970 | "(cons 1 '())\n" | |
971 | "(cons 2 '(1))\n" | |
972 | "(cons 3 '(2 1)\n" | |
973 | "@result{} (3 2 1)\n" | |
974 | "@end example\n" | |
975 | "\n" | |
976 | "If @var{lst1} through @var{lstN} have different lengths,\n" | |
977 | "@code{fold} stops when the end of the shortest is reached.\n" | |
978 | "Ie.@: elements past the length of the shortest are ignored in\n" | |
979 | "the other @var{lst}s. At least one @var{lst} must be\n" | |
980 | "non-circular.\n" | |
981 | "\n" | |
982 | "The way @code{fold} builds a result from iterating is quite\n" | |
983 | "general, it can do more than other iterations like say\n" | |
984 | "@code{map} or @code{filter}. The following for example removes\n" | |
985 | "adjacent duplicate elements from a list,\n" | |
986 | "\n" | |
987 | "@example\n" | |
988 | "(define (delete-adjacent-duplicates lst)\n" | |
989 | " (fold-right (lambda (elem ret)\n" | |
990 | " (if (equal? elem (first ret))\n" | |
991 | " ret\n" | |
992 | " (cons elem ret)))\n" | |
993 | " (list (last lst))\n" | |
994 | " lst))\n" | |
995 | "(delete-adjacent-duplicates '(1 2 3 3 4 4 4 5))\n" | |
996 | "@result{} (1 2 3 4 5)\n" | |
997 | "@end example\n" | |
998 | "\n" | |
999 | "Clearly the same sort of thing can be done with a\n" | |
1000 | "@code{for-each} and a variable in which to build the result,\n" | |
1001 | "but a self-contained @var{proc} can be re-used in multiple\n" | |
1002 | "contexts, where a @code{for-each} would have to be written out\n" | |
1003 | "each time.") | |
1004 | #define FUNC_NAME s_scm_srfi1_fold | |
1005 | { | |
1006 | SCM lst; | |
1007 | int argnum; | |
1008 | SCM_VALIDATE_REST_ARGUMENT (rest); | |
1009 | ||
1010 | if (scm_is_null (rest)) | |
1011 | { | |
1012 | /* one list */ | |
1013 | scm_t_trampoline_2 proc_tramp = scm_trampoline_2 (proc); | |
1014 | SCM_ASSERT (proc_tramp, proc, SCM_ARG1, FUNC_NAME); | |
1015 | ||
1016 | for ( ; scm_is_pair (list1); list1 = SCM_CDR (list1)) | |
1017 | init = proc_tramp (proc, SCM_CAR (list1), init); | |
1018 | ||
1019 | /* check below that list1 is a proper list, and done */ | |
1020 | lst = list1; | |
1021 | argnum = 2; | |
1022 | } | |
1023 | else | |
1024 | { | |
1025 | /* two or more lists */ | |
1026 | SCM vec, args, a; | |
1027 | size_t len, i; | |
1028 | ||
1029 | /* vec is the list arguments */ | |
1030 | vec = scm_vector (scm_cons (list1, rest)); | |
1031 | len = SCM_SIMPLE_VECTOR_LENGTH (vec); | |
1032 | ||
1033 | /* args is the argument list to pass to proc, same length as vec, | |
1034 | re-used for each call */ | |
1035 | args = scm_make_list (SCM_I_MAKINUM (len+1), SCM_UNDEFINED); | |
1036 | ||
1037 | for (;;) | |
1038 | { | |
1039 | /* first elem of each list in vec into args, and step those | |
1040 | vec entries onto their next element */ | |
1041 | for (i = 0, a = args, argnum = 2; | |
1042 | i < len; | |
1043 | i++, a = SCM_CDR (a), argnum++) | |
1044 | { | |
1045 | lst = SCM_SIMPLE_VECTOR_REF (vec, i); /* list argument */ | |
1046 | if (! scm_is_pair (lst)) | |
1047 | goto check_lst_and_done; | |
1048 | SCM_SETCAR (a, SCM_CAR (lst)); /* arg for proc */ | |
1049 | SCM_SIMPLE_VECTOR_SET (vec, i, SCM_CDR (lst)); /* rest of lst */ | |
1050 | } | |
1051 | SCM_SETCAR (a, init); | |
1052 | ||
1053 | init = scm_apply (proc, args, SCM_EOL); | |
1054 | } | |
1055 | } | |
1056 | ||
1057 | check_lst_and_done: | |
1058 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, argnum, FUNC_NAME, "list"); | |
1059 | return init; | |
1060 | } | |
1061 | #undef FUNC_NAME | |
1062 | ||
1063 | ||
1064 | SCM_DEFINE (scm_srfi1_last, "last", 1, 0, 0, | |
1065 | (SCM lst), | |
1066 | "Like @code{cons}, but with interchanged arguments. Useful\n" | |
1067 | "mostly when passed to higher-order procedures.") | |
1068 | #define FUNC_NAME s_scm_srfi1_last | |
1069 | { | |
1070 | SCM pair = scm_last_pair (lst); | |
1071 | /* scm_last_pair returns SCM_EOL for an empty list */ | |
1072 | SCM_VALIDATE_CONS (SCM_ARG1, pair); | |
1073 | return SCM_CAR (pair); | |
1074 | } | |
1075 | #undef FUNC_NAME | |
1076 | ||
1077 | ||
de51f595 KR |
1078 | SCM_DEFINE (scm_srfi1_length_plus, "length+", 1, 0, 0, |
1079 | (SCM lst), | |
1080 | "Return the length of @var{lst}, or @code{#f} if @var{lst} is\n" | |
1081 | "circular.") | |
1082 | #define FUNC_NAME s_scm_srfi1_length_plus | |
1083 | { | |
1084 | long len = scm_ilength (lst); | |
93ccaef0 | 1085 | return (len >= 0 ? SCM_I_MAKINUM (len) : SCM_BOOL_F); |
de51f595 KR |
1086 | } |
1087 | #undef FUNC_NAME | |
1088 | ||
1089 | ||
e556f8c3 KR |
1090 | SCM_DEFINE (scm_srfi1_list_index, "list-index", 2, 0, 1, |
1091 | (SCM pred, SCM list1, SCM rest), | |
1092 | "Return the index of the first set of elements, one from each of\n" | |
1093 | "@var{lst1}@dots{}@var{lstN}, which satisfies @var{pred}.\n" | |
1094 | "\n" | |
1095 | "@var{pred} is called as @code{(@var{pred} elem1 @dots{}\n" | |
1096 | "elemN)}. Searching stops when the end of the shortest\n" | |
1097 | "@var{lst} is reached. The return index starts from 0 for the\n" | |
1098 | "first set of elements. If no set of elements pass then the\n" | |
1099 | "return is @code{#f}.\n" | |
1100 | "\n" | |
1101 | "@example\n" | |
1102 | "(list-index odd? '(2 4 6 9)) @result{} 3\n" | |
1103 | "(list-index = '(1 2 3) '(3 1 2)) @result{} #f\n" | |
1104 | "@end example") | |
1105 | #define FUNC_NAME s_scm_srfi1_list_index | |
1106 | { | |
1107 | long n = 0; | |
1108 | SCM lst; | |
1109 | int argnum; | |
1110 | SCM_VALIDATE_REST_ARGUMENT (rest); | |
1111 | ||
1112 | if (scm_is_null (rest)) | |
1113 | { | |
1114 | /* one list */ | |
1115 | scm_t_trampoline_1 pred_tramp = scm_trampoline_1 (pred); | |
1116 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
1117 | ||
1118 | for ( ; scm_is_pair (list1); n++, list1 = SCM_CDR (list1)) | |
1119 | if (scm_is_true (pred_tramp (pred, SCM_CAR (list1)))) | |
1120 | return SCM_I_MAKINUM (n); | |
1121 | ||
1122 | /* not found, check below that list1 is a proper list */ | |
1123 | end_list1: | |
1124 | lst = list1; | |
1125 | argnum = 2; | |
1126 | } | |
1127 | else if (scm_is_pair (rest) && scm_is_null (SCM_CDR (rest))) | |
1128 | { | |
1129 | /* two lists */ | |
1130 | SCM list2 = SCM_CAR (rest); | |
1131 | scm_t_trampoline_2 pred_tramp = scm_trampoline_2 (pred); | |
1132 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
1133 | ||
1134 | for ( ; ; n++) | |
1135 | { | |
1136 | if (! scm_is_pair (list1)) | |
1137 | goto end_list1; | |
1138 | if (! scm_is_pair (list2)) | |
1139 | { | |
1140 | lst = list2; | |
1141 | argnum = 3; | |
1142 | break; | |
1143 | } | |
1144 | if (scm_is_true (pred_tramp (pred, | |
1145 | SCM_CAR (list1), SCM_CAR (list2)))) | |
1146 | return SCM_I_MAKINUM (n); | |
1147 | ||
1148 | list1 = SCM_CDR (list1); | |
1149 | list2 = SCM_CDR (list2); | |
1150 | } | |
1151 | } | |
1152 | else | |
1153 | { | |
1154 | /* three or more lists */ | |
1155 | SCM vec, args, a; | |
1156 | size_t len, i; | |
1157 | ||
1158 | /* vec is the list arguments */ | |
1159 | vec = scm_vector (scm_cons (list1, rest)); | |
1160 | len = SCM_SIMPLE_VECTOR_LENGTH (vec); | |
1161 | ||
1162 | /* args is the argument list to pass to pred, same length as vec, | |
1163 | re-used for each call */ | |
1164 | args = scm_make_list (SCM_I_MAKINUM (len), SCM_UNDEFINED); | |
1165 | ||
1166 | for ( ; ; n++) | |
1167 | { | |
1168 | /* first elem of each list in vec into args, and step those | |
1169 | vec entries onto their next element */ | |
1170 | for (i = 0, a = args, argnum = 2; | |
1171 | i < len; | |
1172 | i++, a = SCM_CDR (a), argnum++) | |
1173 | { | |
1174 | lst = SCM_SIMPLE_VECTOR_REF (vec, i); /* list argument */ | |
1175 | if (! scm_is_pair (lst)) | |
1176 | goto not_found_check_lst; | |
1177 | SCM_SETCAR (a, SCM_CAR (lst)); /* arg for pred */ | |
1178 | SCM_SIMPLE_VECTOR_SET (vec, i, SCM_CDR (lst)); /* rest of lst */ | |
1179 | } | |
1180 | ||
1181 | if (scm_is_true (scm_apply (pred, args, SCM_EOL))) | |
1182 | return SCM_I_MAKINUM (n); | |
1183 | } | |
1184 | } | |
1185 | ||
1186 | not_found_check_lst: | |
1187 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, argnum, FUNC_NAME, "list"); | |
1188 | return SCM_BOOL_F; | |
1189 | } | |
1190 | #undef FUNC_NAME | |
1191 | ||
1192 | ||
d61261f0 KR |
1193 | /* This routine differs from the core list-copy in allowing improper lists. |
1194 | Maybe the core could allow them similarly. */ | |
1195 | ||
1196 | SCM_DEFINE (scm_srfi1_list_copy, "list-copy", 1, 0, 0, | |
1197 | (SCM lst), | |
1198 | "Return a copy of the given list @var{lst}.\n" | |
1199 | "\n" | |
1200 | "@var{lst} can be a proper or improper list. And if @var{lst}\n" | |
1201 | "is not a pair then it's treated as the final tail of an\n" | |
1202 | "improper list and simply returned.") | |
1203 | #define FUNC_NAME s_scm_srfi1_list_copy | |
1204 | { | |
1205 | SCM newlst; | |
1206 | SCM * fill_here; | |
1207 | SCM from_here; | |
1208 | ||
1209 | newlst = lst; | |
1210 | fill_here = &newlst; | |
1211 | from_here = lst; | |
1212 | ||
896df2d5 | 1213 | while (scm_is_pair (from_here)) |
d61261f0 KR |
1214 | { |
1215 | SCM c; | |
1216 | c = scm_cons (SCM_CAR (from_here), SCM_CDR (from_here)); | |
1217 | *fill_here = c; | |
1218 | fill_here = SCM_CDRLOC (c); | |
1219 | from_here = SCM_CDR (from_here); | |
1220 | } | |
1221 | return newlst; | |
1222 | } | |
1223 | #undef FUNC_NAME | |
1224 | ||
1225 | ||
e556f8c3 KR |
1226 | SCM_DEFINE (scm_srfi1_list_tabulate, "list-tabulate", 2, 0, 0, |
1227 | (SCM n, SCM proc), | |
1228 | "Return an @var{n}-element list, where each list element is\n" | |
1229 | "produced by applying the procedure @var{init-proc} to the\n" | |
1230 | "corresponding list index. The order in which @var{init-proc}\n" | |
1231 | "is applied to the indices is not specified.") | |
1232 | #define FUNC_NAME s_scm_srfi1_list_tabulate | |
1233 | { | |
1234 | long i, nn; | |
1235 | scm_t_trampoline_1 proc_tramp = scm_trampoline_1 (proc); | |
1236 | SCM ret = SCM_EOL; | |
1237 | ||
b730fbf1 | 1238 | nn = scm_to_signed_integer (n, 0, LONG_MAX); |
e556f8c3 KR |
1239 | SCM_ASSERT (proc_tramp, proc, SCM_ARG2, FUNC_NAME); |
1240 | ||
1241 | for (i = nn-1; i >= 0; i--) | |
b730fbf1 | 1242 | ret = scm_cons (proc_tramp (proc, scm_from_long (i)), ret); |
e556f8c3 KR |
1243 | |
1244 | return ret; | |
1245 | } | |
1246 | #undef FUNC_NAME | |
1247 | ||
1248 | ||
597dbd4e KR |
1249 | SCM_DEFINE (scm_srfi1_lset_adjoin, "lset-adjoin", 2, 0, 1, |
1250 | (SCM equal, SCM lst, SCM rest), | |
1251 | "Add to @var{list} any of the given @var{elem}s not already in\n" | |
1252 | "the list. @var{elem}s are @code{cons}ed onto the start of\n" | |
1253 | "@var{list} (so the return shares a common tail with\n" | |
1254 | "@var{list}), but the order they're added is unspecified.\n" | |
1255 | "\n" | |
1256 | "The given @var{=} procedure is used for comparing elements,\n" | |
1257 | "called as @code{(@var{=} listelem elem)}, ie.@: the second\n" | |
1258 | "argument is one of the given @var{elem} parameters.\n" | |
1259 | "\n" | |
1260 | "@example\n" | |
1261 | "(lset-adjoin eqv? '(1 2 3) 4 1 5) @result{} (5 4 1 2 3)\n" | |
1262 | "@end example") | |
1263 | #define FUNC_NAME s_scm_srfi1_lset_adjoin | |
1264 | { | |
1265 | scm_t_trampoline_2 equal_tramp; | |
1266 | SCM l, elem; | |
1267 | ||
1268 | equal_tramp = scm_trampoline_2 (equal); | |
1269 | SCM_ASSERT (equal_tramp, equal, SCM_ARG1, FUNC_NAME); | |
1270 | SCM_VALIDATE_REST_ARGUMENT (rest); | |
1271 | ||
1272 | /* It's not clear if duplicates among the `rest' elements are meant to be | |
1273 | cast out. The spec says `=' is called as (= list-elem rest-elem), | |
1274 | suggesting perhaps not, but the reference implementation shows the | |
1275 | "list" at each stage as including those "rest" elements already added. | |
1276 | The latter corresponds to what's described for lset-union, so that's | |
1277 | what's done here. */ | |
1278 | ||
1279 | for ( ; scm_is_pair (rest); rest = SCM_CDR (rest)) | |
1280 | { | |
1281 | elem = SCM_CAR (rest); | |
1282 | ||
1283 | for (l = lst; scm_is_pair (l); l = SCM_CDR (l)) | |
1284 | if (scm_is_true (equal_tramp (equal, SCM_CAR (l), elem))) | |
1285 | goto next_elem; /* elem already in lst, don't add */ | |
1286 | ||
1287 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P(l), lst, SCM_ARG2, FUNC_NAME, "list"); | |
1288 | ||
1289 | /* elem is not equal to anything already in lst, add it */ | |
1290 | lst = scm_cons (elem, lst); | |
1291 | ||
1292 | next_elem: | |
1293 | ; | |
1294 | } | |
1295 | ||
1296 | return lst; | |
1297 | } | |
1298 | #undef FUNC_NAME | |
1299 | ||
1300 | ||
9dcee2b7 KR |
1301 | SCM_DEFINE (scm_srfi1_lset_difference_x, "lset-difference!", 2, 0, 1, |
1302 | (SCM equal, SCM lst, SCM rest), | |
1303 | "Return @var{lst} with any elements in the lists in @var{rest}\n" | |
1304 | "removed (ie.@: subtracted). For only one @var{lst} argument,\n" | |
1305 | "just that list is returned.\n" | |
1306 | "\n" | |
1307 | "The given @var{equal} procedure is used for comparing elements,\n" | |
1308 | "called as @code{(@var{equal} elem1 elemN)}. The first argument\n" | |
1309 | "is from @var{lst} and the second from one of the subsequent\n" | |
1310 | "lists. But exactly which calls are made and in what order is\n" | |
1311 | "unspecified.\n" | |
1312 | "\n" | |
1313 | "@example\n" | |
1314 | "(lset-difference! eqv? (list 'x 'y)) @result{} (x y)\n" | |
1315 | "(lset-difference! eqv? (list 1 2 3) '(3 1)) @result{} (2)\n" | |
1316 | "(lset-difference! eqv? (list 1 2 3) '(3) '(2)) @result{} (1)\n" | |
1317 | "@end example\n" | |
1318 | "\n" | |
1319 | "@code{lset-difference!} may modify @var{lst} to form its\n" | |
1320 | "result.") | |
1321 | #define FUNC_NAME s_scm_srfi1_lset_difference_x | |
1322 | { | |
1323 | scm_t_trampoline_2 equal_tramp = scm_trampoline_2 (equal); | |
1324 | SCM ret, *pos, elem, r, b; | |
1325 | int argnum; | |
1326 | ||
1327 | SCM_ASSERT (equal_tramp, equal, SCM_ARG1, FUNC_NAME); | |
1328 | SCM_VALIDATE_REST_ARGUMENT (rest); | |
1329 | ||
1330 | ret = SCM_EOL; | |
1331 | pos = &ret; | |
1332 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) | |
1333 | { | |
1334 | elem = SCM_CAR (lst); | |
1335 | ||
1336 | for (r = rest, argnum = SCM_ARG3; | |
1337 | scm_is_pair (r); | |
1338 | r = SCM_CDR (r), argnum++) | |
1339 | { | |
1340 | for (b = SCM_CAR (r); scm_is_pair (b); b = SCM_CDR (b)) | |
1341 | if (scm_is_true (equal_tramp (equal, elem, SCM_CAR (b)))) | |
1342 | goto next_elem; /* equal to elem, so drop that elem */ | |
1343 | ||
1344 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (b), b, argnum, FUNC_NAME,"list"); | |
1345 | } | |
1346 | ||
1347 | /* elem not equal to anything in later lists, so keep it */ | |
1348 | *pos = lst; | |
1349 | pos = SCM_CDRLOC (lst); | |
1350 | ||
1351 | next_elem: | |
1352 | ; | |
1353 | } | |
1354 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG2, FUNC_NAME, "list"); | |
1355 | ||
1356 | *pos = SCM_EOL; | |
1357 | return ret; | |
1358 | } | |
1359 | #undef FUNC_NAME | |
1360 | ||
1361 | ||
ee6aac97 MD |
1362 | /* Typechecking for multi-argument MAP and FOR-EACH. |
1363 | ||
1364 | Verify that each element of the vector ARGV, except for the first, | |
1365 | is a list and return minimum length. Attribute errors to WHO, | |
1366 | and claim that the i'th element of ARGV is WHO's i+2'th argument. */ | |
1367 | static inline int | |
1368 | check_map_args (SCM argv, | |
1369 | long len, | |
1370 | SCM gf, | |
1371 | SCM proc, | |
1372 | SCM args, | |
1373 | const char *who) | |
1374 | { | |
ee6aac97 | 1375 | long i; |
705f4f57 | 1376 | SCM elt; |
ee6aac97 | 1377 | |
3c4ce91b | 1378 | for (i = SCM_SIMPLE_VECTOR_LENGTH (argv) - 1; i >= 1; i--) |
ee6aac97 MD |
1379 | { |
1380 | long elt_len; | |
705f4f57 | 1381 | elt = SCM_SIMPLE_VECTOR_REF (argv, i); |
ee6aac97 | 1382 | |
896df2d5 | 1383 | if (!(scm_is_null (elt) || scm_is_pair (elt))) |
705f4f57 | 1384 | goto check_map_error; |
ee6aac97 | 1385 | |
3c4ce91b | 1386 | elt_len = srfi1_ilength (elt); |
ee6aac97 MD |
1387 | if (elt_len < -1) |
1388 | goto check_map_error; | |
1389 | ||
1390 | if (len < 0 || (elt_len >= 0 && elt_len < len)) | |
1391 | len = elt_len; | |
1392 | } | |
705f4f57 | 1393 | |
ee6aac97 | 1394 | if (len < 0) |
705f4f57 MV |
1395 | { |
1396 | /* i == 0 */ | |
1397 | elt = SCM_EOL; | |
1398 | check_map_error: | |
1399 | if (gf) | |
1400 | scm_apply_generic (gf, scm_cons (proc, args)); | |
1401 | else | |
1402 | scm_wrong_type_arg (who, i + 2, elt); | |
1403 | } | |
1404 | ||
ee6aac97 MD |
1405 | scm_remember_upto_here_1 (argv); |
1406 | return len; | |
1407 | } | |
1408 | ||
1409 | ||
1410 | SCM_GPROC (s_srfi1_map, "map", 2, 0, 1, scm_srfi1_map, g_srfi1_map); | |
1411 | ||
1412 | /* Note: Currently, scm_srfi1_map applies PROC to the argument list(s) | |
1413 | sequentially, starting with the first element(s). This is used in | |
1414 | the Scheme procedure `map-in-order', which guarantees sequential | |
1415 | behaviour, is implemented using scm_map. If the behaviour changes, | |
1416 | we need to update `map-in-order'. | |
1417 | */ | |
1418 | ||
1419 | SCM | |
1420 | scm_srfi1_map (SCM proc, SCM arg1, SCM args) | |
1421 | #define FUNC_NAME s_srfi1_map | |
1422 | { | |
1423 | long i, len; | |
1424 | SCM res = SCM_EOL; | |
1425 | SCM *pres = &res; | |
ee6aac97 MD |
1426 | |
1427 | len = srfi1_ilength (arg1); | |
896df2d5 | 1428 | SCM_GASSERTn ((scm_is_null (arg1) || scm_is_pair (arg1)) && len >= -1, |
ee6aac97 MD |
1429 | g_srfi1_map, |
1430 | scm_cons2 (proc, arg1, args), SCM_ARG2, s_srfi1_map); | |
1431 | SCM_VALIDATE_REST_ARGUMENT (args); | |
896df2d5 | 1432 | if (scm_is_null (args)) |
ee6aac97 MD |
1433 | { |
1434 | scm_t_trampoline_1 call = scm_trampoline_1 (proc); | |
1435 | SCM_GASSERT2 (call, g_srfi1_map, proc, arg1, SCM_ARG1, s_srfi1_map); | |
1436 | SCM_GASSERT2 (len >= 0, g_srfi1_map, proc, arg1, SCM_ARG2, s_srfi1_map); | |
1437 | while (SCM_NIMP (arg1)) | |
1438 | { | |
1439 | *pres = scm_list_1 (call (proc, SCM_CAR (arg1))); | |
1440 | pres = SCM_CDRLOC (*pres); | |
1441 | arg1 = SCM_CDR (arg1); | |
1442 | } | |
1443 | return res; | |
1444 | } | |
896df2d5 | 1445 | if (scm_is_null (SCM_CDR (args))) |
ee6aac97 MD |
1446 | { |
1447 | SCM arg2 = SCM_CAR (args); | |
1448 | int len2 = srfi1_ilength (arg2); | |
1449 | scm_t_trampoline_2 call = scm_trampoline_2 (proc); | |
1450 | SCM_GASSERTn (call, g_srfi1_map, | |
1451 | scm_cons2 (proc, arg1, args), SCM_ARG1, s_srfi1_map); | |
1452 | if (len < 0 || (len2 >= 0 && len2 < len)) | |
1453 | len = len2; | |
896df2d5 | 1454 | SCM_GASSERTn ((scm_is_null (arg2) || scm_is_pair (arg2)) |
ee6aac97 MD |
1455 | && len >= 0 && len2 >= -1, |
1456 | g_srfi1_map, | |
1457 | scm_cons2 (proc, arg1, args), | |
f9ac1c2d | 1458 | len2 >= 0 ? SCM_ARG2 : SCM_ARG3, |
ee6aac97 MD |
1459 | s_srfi1_map); |
1460 | while (len > 0) | |
1461 | { | |
1462 | *pres = scm_list_1 (call (proc, SCM_CAR (arg1), SCM_CAR (arg2))); | |
1463 | pres = SCM_CDRLOC (*pres); | |
1464 | arg1 = SCM_CDR (arg1); | |
1465 | arg2 = SCM_CDR (arg2); | |
1466 | --len; | |
1467 | } | |
1468 | return res; | |
1469 | } | |
1470 | args = scm_vector (arg1 = scm_cons (arg1, args)); | |
ee6aac97 MD |
1471 | len = check_map_args (args, len, g_srfi1_map, proc, arg1, s_srfi1_map); |
1472 | while (len > 0) | |
1473 | { | |
1474 | arg1 = SCM_EOL; | |
3c4ce91b | 1475 | for (i = SCM_SIMPLE_VECTOR_LENGTH (args) - 1; i >= 0; i--) |
ee6aac97 | 1476 | { |
3c4ce91b MV |
1477 | SCM elt = SCM_SIMPLE_VECTOR_REF (args, i); |
1478 | arg1 = scm_cons (SCM_CAR (elt), arg1); | |
1479 | SCM_SIMPLE_VECTOR_SET (args, i, SCM_CDR (elt)); | |
ee6aac97 MD |
1480 | } |
1481 | *pres = scm_list_1 (scm_apply (proc, arg1, SCM_EOL)); | |
1482 | pres = SCM_CDRLOC (*pres); | |
1483 | --len; | |
1484 | } | |
1485 | return res; | |
1486 | } | |
1487 | #undef FUNC_NAME | |
1488 | ||
1489 | SCM_REGISTER_PROC (s_srfi1_map_in_order, "map-in-order", 2, 0, 1, scm_srfi1_map); | |
1490 | ||
1491 | SCM_GPROC (s_srfi1_for_each, "for-each", 2, 0, 1, scm_srfi1_for_each, g_srfi1_for_each); | |
1492 | ||
1493 | SCM | |
1494 | scm_srfi1_for_each (SCM proc, SCM arg1, SCM args) | |
1495 | #define FUNC_NAME s_srfi1_for_each | |
1496 | { | |
ee6aac97 MD |
1497 | long i, len; |
1498 | len = srfi1_ilength (arg1); | |
896df2d5 | 1499 | SCM_GASSERTn ((scm_is_null (arg1) || scm_is_pair (arg1)) && len >= -1, |
ee6aac97 MD |
1500 | g_srfi1_for_each, scm_cons2 (proc, arg1, args), |
1501 | SCM_ARG2, s_srfi1_for_each); | |
1502 | SCM_VALIDATE_REST_ARGUMENT (args); | |
896df2d5 | 1503 | if (scm_is_null (args)) |
ee6aac97 MD |
1504 | { |
1505 | scm_t_trampoline_1 call = scm_trampoline_1 (proc); | |
1506 | SCM_GASSERT2 (call, g_srfi1_for_each, proc, arg1, | |
1507 | SCM_ARG1, s_srfi1_for_each); | |
1508 | SCM_GASSERT2 (len >= 0, g_srfi1_for_each, proc, arg1, | |
1509 | SCM_ARG2, s_srfi1_map); | |
1510 | while (SCM_NIMP (arg1)) | |
1511 | { | |
1512 | call (proc, SCM_CAR (arg1)); | |
1513 | arg1 = SCM_CDR (arg1); | |
1514 | } | |
1515 | return SCM_UNSPECIFIED; | |
1516 | } | |
896df2d5 | 1517 | if (scm_is_null (SCM_CDR (args))) |
ee6aac97 MD |
1518 | { |
1519 | SCM arg2 = SCM_CAR (args); | |
1520 | int len2 = srfi1_ilength (arg2); | |
1521 | scm_t_trampoline_2 call = scm_trampoline_2 (proc); | |
1522 | SCM_GASSERTn (call, g_srfi1_for_each, | |
1523 | scm_cons2 (proc, arg1, args), SCM_ARG1, s_srfi1_for_each); | |
1524 | if (len < 0 || (len2 >= 0 && len2 < len)) | |
1525 | len = len2; | |
896df2d5 | 1526 | SCM_GASSERTn ((scm_is_null (arg2) || scm_is_pair (arg2)) |
f9ac1c2d | 1527 | && len >= 0 && len2 >= -1, |
ee6aac97 MD |
1528 | g_srfi1_for_each, |
1529 | scm_cons2 (proc, arg1, args), | |
f9ac1c2d | 1530 | len2 >= 0 ? SCM_ARG2 : SCM_ARG3, |
ee6aac97 MD |
1531 | s_srfi1_for_each); |
1532 | while (len > 0) | |
1533 | { | |
1534 | call (proc, SCM_CAR (arg1), SCM_CAR (arg2)); | |
1535 | arg1 = SCM_CDR (arg1); | |
1536 | arg2 = SCM_CDR (arg2); | |
1537 | --len; | |
1538 | } | |
1539 | return SCM_UNSPECIFIED; | |
1540 | } | |
1541 | args = scm_vector (arg1 = scm_cons (arg1, args)); | |
ee6aac97 MD |
1542 | len = check_map_args (args, len, g_srfi1_for_each, proc, arg1, |
1543 | s_srfi1_for_each); | |
1544 | while (len > 0) | |
1545 | { | |
1546 | arg1 = SCM_EOL; | |
3c4ce91b | 1547 | for (i = SCM_SIMPLE_VECTOR_LENGTH (args) - 1; i >= 0; i--) |
ee6aac97 | 1548 | { |
3c4ce91b MV |
1549 | SCM elt = SCM_SIMPLE_VECTOR_REF (args, i); |
1550 | arg1 = scm_cons (SCM_CAR (elt), arg1); | |
1551 | SCM_SIMPLE_VECTOR_SET (args, i, SCM_CDR (elt)); | |
ee6aac97 MD |
1552 | } |
1553 | scm_apply (proc, arg1, SCM_EOL); | |
1554 | --len; | |
1555 | } | |
1556 | return SCM_UNSPECIFIED; | |
1557 | } | |
1558 | #undef FUNC_NAME | |
1559 | ||
1560 | ||
ee6aac97 MD |
1561 | SCM_DEFINE (scm_srfi1_member, "member", 2, 1, 0, |
1562 | (SCM x, SCM lst, SCM pred), | |
4e3cc389 KR |
1563 | "Return the first sublist of @var{lst} whose @sc{car} is equal\n" |
1564 | "to @var{x}. If @var{x} does not appear in @var{lst}, return\n" | |
1565 | "@code{#f}.\n" | |
1566 | "\n" | |
1567 | "Equality is determined by @code{equal?}, or by the equality\n" | |
1568 | "predicate @var{=} if given. @var{=} is called @code{(= @var{x}\n" | |
1569 | "elem)}, ie.@: with the given @var{x} first, so for example to\n" | |
1570 | "find the first element greater than 5,\n" | |
1571 | "\n" | |
1572 | "@example\n" | |
1573 | "(member 5 '(3 5 1 7 2 9) <) @result{} (7 2 9)\n" | |
1574 | "@end example\n" | |
1575 | "\n" | |
1576 | "This version of @code{member} extends the core @code{member} by\n" | |
1577 | "accepting an equality predicate.") | |
ee6aac97 MD |
1578 | #define FUNC_NAME s_scm_srfi1_member |
1579 | { | |
1580 | scm_t_trampoline_2 equal_p; | |
1581 | SCM_VALIDATE_LIST (2, lst); | |
1582 | if (SCM_UNBNDP (pred)) | |
1583 | equal_p = equal_trampoline; | |
1584 | else | |
1585 | { | |
1586 | equal_p = scm_trampoline_2 (pred); | |
1587 | SCM_ASSERT (equal_p, pred, 3, FUNC_NAME); | |
1588 | } | |
1589 | for (; !SCM_NULL_OR_NIL_P (lst); lst = SCM_CDR (lst)) | |
1590 | { | |
2796304a | 1591 | if (scm_is_true (equal_p (pred, x, SCM_CAR (lst)))) |
ee6aac97 MD |
1592 | return lst; |
1593 | } | |
1594 | return SCM_BOOL_F; | |
1595 | } | |
1596 | #undef FUNC_NAME | |
1597 | ||
7692d26b MD |
1598 | SCM_DEFINE (scm_srfi1_assoc, "assoc", 2, 1, 0, |
1599 | (SCM key, SCM alist, SCM pred), | |
1600 | "Behaves like @code{assq} but uses third argument @var{pred?}\n" | |
1601 | "for key comparison. If @var{pred?} is not supplied,\n" | |
1602 | "@code{equal?} is used. (Extended from R5RS.)\n") | |
1603 | #define FUNC_NAME s_scm_srfi1_assoc | |
1604 | { | |
1605 | SCM ls = alist; | |
1606 | scm_t_trampoline_2 equal_p; | |
1607 | if (SCM_UNBNDP (pred)) | |
1608 | equal_p = equal_trampoline; | |
1609 | else | |
1610 | { | |
1611 | equal_p = scm_trampoline_2 (pred); | |
1612 | SCM_ASSERT (equal_p, pred, 3, FUNC_NAME); | |
1613 | } | |
896df2d5 | 1614 | for(; scm_is_pair (ls); ls = SCM_CDR (ls)) |
7692d26b MD |
1615 | { |
1616 | SCM tmp = SCM_CAR (ls); | |
896df2d5 | 1617 | SCM_ASSERT_TYPE (scm_is_pair (tmp), alist, SCM_ARG2, FUNC_NAME, |
7692d26b | 1618 | "association list"); |
9a993171 | 1619 | if (scm_is_true (equal_p (pred, key, SCM_CAR (tmp)))) |
7692d26b MD |
1620 | return tmp; |
1621 | } | |
1622 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (ls), alist, SCM_ARG2, FUNC_NAME, | |
1623 | "association list"); | |
1624 | return SCM_BOOL_F; | |
1625 | } | |
1626 | #undef FUNC_NAME | |
1627 | ||
03731332 KR |
1628 | |
1629 | SCM_DEFINE (scm_srfi1_ninth, "ninth", 1, 0, 0, | |
1630 | (SCM lst), | |
1631 | "Return the ninth element of @var{lst}.") | |
1632 | #define FUNC_NAME s_scm_srfi1_ninth | |
1633 | { | |
b730fbf1 | 1634 | return scm_list_ref (lst, scm_from_int (8)); |
03731332 KR |
1635 | } |
1636 | #undef FUNC_NAME | |
1637 | ||
1638 | ||
e556f8c3 KR |
1639 | SCM_DEFINE (scm_srfi1_not_pair_p, "not-pair?", 1, 0, 0, |
1640 | (SCM obj), | |
1641 | "Return @code{#t} is @var{obj} is not a pair, @code{#f}\n" | |
1642 | "otherwise.\n" | |
1643 | "\n" | |
1644 | "This is shorthand notation @code{(not (pair? @var{obj}))} and\n" | |
1645 | "is supposed to be used for end-of-list checking in contexts\n" | |
1646 | "where dotted lists are allowed.") | |
1647 | #define FUNC_NAME s_scm_srfi1_not_pair_p | |
1648 | { | |
1649 | return scm_from_bool (! scm_is_pair (obj)); | |
1650 | } | |
1651 | #undef FUNC_NAME | |
1652 | ||
1653 | ||
65978fb2 KR |
1654 | SCM_DEFINE (scm_srfi1_partition, "partition", 2, 0, 0, |
1655 | (SCM pred, SCM list), | |
1656 | "Partition the elements of @var{list} with predicate @var{pred}.\n" | |
1657 | "Return two values: the list of elements satifying @var{pred} and\n" | |
1658 | "the list of elements @emph{not} satisfying @var{pred}. The order\n" | |
1659 | "of the output lists follows the order of @var{list}. @var{list}\n" | |
1660 | "is not mutated. One of the output lists may share memory with @var{list}.\n") | |
1661 | #define FUNC_NAME s_scm_srfi1_partition | |
1662 | { | |
1663 | /* In this implementation, the output lists don't share memory with | |
1664 | list, because it's probably not worth the effort. */ | |
1665 | scm_t_trampoline_1 call = scm_trampoline_1(pred); | |
1666 | SCM kept = scm_cons(SCM_EOL, SCM_EOL); | |
1667 | SCM kept_tail = kept; | |
1668 | SCM dropped = scm_cons(SCM_EOL, SCM_EOL); | |
1669 | SCM dropped_tail = dropped; | |
1670 | ||
1671 | SCM_ASSERT(call, pred, 2, FUNC_NAME); | |
1672 | ||
1673 | for (; !SCM_NULL_OR_NIL_P (list); list = SCM_CDR(list)) { | |
1674 | SCM elt = SCM_CAR(list); | |
1675 | SCM new_tail = scm_cons(SCM_CAR(list), SCM_EOL); | |
00874d5f | 1676 | if (scm_is_true (call (pred, elt))) { |
65978fb2 KR |
1677 | SCM_SETCDR(kept_tail, new_tail); |
1678 | kept_tail = new_tail; | |
1679 | } | |
1680 | else { | |
1681 | SCM_SETCDR(dropped_tail, new_tail); | |
1682 | dropped_tail = new_tail; | |
1683 | } | |
1684 | } | |
1685 | /* re-use the initial conses for the values list */ | |
1686 | SCM_SETCAR(kept, SCM_CDR(kept)); | |
1687 | SCM_SETCDR(kept, dropped); | |
1688 | SCM_SETCAR(dropped, SCM_CDR(dropped)); | |
1689 | SCM_SETCDR(dropped, SCM_EOL); | |
1690 | return scm_values(kept); | |
1691 | } | |
1692 | #undef FUNC_NAME | |
1693 | ||
2b077051 KR |
1694 | |
1695 | SCM_DEFINE (scm_srfi1_partition_x, "partition!", 2, 0, 0, | |
1696 | (SCM pred, SCM lst), | |
1697 | "Split @var{lst} into those elements which do and don't satisfy\n" | |
1698 | "the predicate @var{pred}.\n" | |
1699 | "\n" | |
1700 | "The return is two values (@pxref{Multiple Values}), the first\n" | |
1701 | "being a list of all elements from @var{lst} which satisfy\n" | |
1702 | "@var{pred}, the second a list of those which do not.\n" | |
1703 | "\n" | |
1704 | "The elements in the result lists are in the same order as in\n" | |
1705 | "@var{lst} but the order in which the calls @code{(@var{pred}\n" | |
1706 | "elem)} are made on the list elements is unspecified.\n" | |
1707 | "\n" | |
1708 | "@var{lst} may be modified to construct the return lists.") | |
1709 | #define FUNC_NAME s_scm_srfi1_partition_x | |
1710 | { | |
1711 | SCM tlst, flst, *tp, *fp; | |
1712 | scm_t_trampoline_1 pred_tramp; | |
1713 | ||
1714 | pred_tramp = scm_trampoline_1 (pred); | |
1715 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
1716 | ||
1717 | /* tlst and flst are the lists of true and false elements. tp and fp are | |
1718 | where to store to append to them, initially &tlst and &flst, then | |
1719 | SCM_CDRLOC of the last pair in the respective lists. */ | |
1720 | ||
1721 | tlst = SCM_EOL; | |
1722 | flst = SCM_EOL; | |
1723 | tp = &tlst; | |
1724 | fp = &flst; | |
1725 | ||
1726 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) | |
1727 | { | |
1728 | if (scm_is_true (pred_tramp (pred, SCM_CAR (lst)))) | |
1729 | { | |
1730 | *tp = lst; | |
1731 | tp = SCM_CDRLOC (lst); | |
1732 | } | |
1733 | else | |
1734 | { | |
1735 | *fp = lst; | |
1736 | fp = SCM_CDRLOC (lst); | |
1737 | } | |
1738 | } | |
1739 | ||
1740 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG2, FUNC_NAME, "list"); | |
1741 | ||
1742 | /* terminate whichever didn't get the last element(s) */ | |
1743 | *tp = SCM_EOL; | |
1744 | *fp = SCM_EOL; | |
1745 | ||
1746 | return scm_values (scm_list_2 (tlst, flst)); | |
1747 | } | |
1748 | #undef FUNC_NAME | |
1749 | ||
1750 | ||
597dbd4e KR |
1751 | SCM_DEFINE (scm_srfi1_reduce, "reduce", 3, 0, 0, |
1752 | (SCM proc, SCM def, SCM lst), | |
1753 | "@code{reduce} is a variant of @code{fold}, where the first call\n" | |
1754 | "to @var{proc} is on two elements from @var{lst}, rather than\n" | |
1755 | "one element and a given initial value.\n" | |
1756 | "\n" | |
1757 | "If @var{lst} is empty, @code{reduce} returns @var{def} (this is\n" | |
1758 | "the only use for @var{def}). If @var{lst} has just one element\n" | |
1759 | "then that's the return value. Otherwise @var{proc} is called\n" | |
1760 | "on the elements of @var{lst}.\n" | |
1761 | "\n" | |
1762 | "Each @var{proc} call is @code{(@var{proc} @var{elem}\n" | |
1763 | "@var{previous})}, where @var{elem} is from @var{lst} (the\n" | |
1764 | "second and subsequent elements of @var{lst}), and\n" | |
1765 | "@var{previous} is the return from the previous call to\n" | |
1766 | "@var{proc}. The first element of @var{lst} is the\n" | |
1767 | "@var{previous} for the first call to @var{proc}.\n" | |
1768 | "\n" | |
1769 | "For example, the following adds a list of numbers, the calls\n" | |
1770 | "made to @code{+} are shown. (Of course @code{+} accepts\n" | |
1771 | "multiple arguments and can add a list directly, with\n" | |
1772 | "@code{apply}.)\n" | |
1773 | "\n" | |
1774 | "@example\n" | |
1775 | "(reduce + 0 '(5 6 7)) @result{} 18\n" | |
1776 | "\n" | |
1777 | "(+ 6 5) @result{} 11\n" | |
1778 | "(+ 7 11) @result{} 18\n" | |
1779 | "@end example\n" | |
1780 | "\n" | |
1781 | "@code{reduce} can be used instead of @code{fold} where the\n" | |
1782 | "@var{init} value is an ``identity'', meaning a value which\n" | |
1783 | "under @var{proc} doesn't change the result, in this case 0 is\n" | |
1784 | "an identity since @code{(+ 5 0)} is just 5. @code{reduce}\n" | |
1785 | "avoids that unnecessary call.") | |
1786 | #define FUNC_NAME s_scm_srfi1_reduce | |
1787 | { | |
1788 | scm_t_trampoline_2 proc_tramp = scm_trampoline_2 (proc); | |
1789 | SCM ret; | |
1790 | ||
1791 | SCM_ASSERT (proc_tramp, proc, SCM_ARG1, FUNC_NAME); | |
1792 | ||
1793 | ret = def; /* if lst is empty */ | |
1794 | if (scm_is_pair (lst)) | |
1795 | { | |
1796 | ret = SCM_CAR (lst); /* if lst has one element */ | |
1797 | ||
1798 | for (lst = SCM_CDR (lst); scm_is_pair (lst); lst = SCM_CDR (lst)) | |
1799 | ret = proc_tramp (proc, SCM_CAR (lst), ret); | |
1800 | } | |
1801 | ||
1802 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG3, FUNC_NAME, "list"); | |
1803 | return ret; | |
1804 | } | |
1805 | #undef FUNC_NAME | |
1806 | ||
1807 | ||
1808 | SCM_DEFINE (scm_srfi1_reduce_right, "reduce-right", 3, 0, 0, | |
1809 | (SCM proc, SCM def, SCM lst), | |
1810 | "@code{reduce-right} is a variant of @code{fold-right}, where\n" | |
1811 | "the first call to @var{proc} is on two elements from @var{lst},\n" | |
1812 | "rather than one element and a given initial value.\n" | |
1813 | "\n" | |
1814 | "If @var{lst} is empty, @code{reduce-right} returns @var{def}\n" | |
1815 | "(this is the only use for @var{def}). If @var{lst} has just\n" | |
1816 | "one element then that's the return value. Otherwise @var{proc}\n" | |
1817 | "is called on the elements of @var{lst}.\n" | |
1818 | "\n" | |
1819 | "Each @var{proc} call is @code{(@var{proc} @var{elem}\n" | |
1820 | "@var{previous})}, where @var{elem} is from @var{lst} (the\n" | |
1821 | "second last and then working back to the first element of\n" | |
1822 | "@var{lst}), and @var{previous} is the return from the previous\n" | |
1823 | "call to @var{proc}. The last element of @var{lst} is the\n" | |
1824 | "@var{previous} for the first call to @var{proc}.\n" | |
1825 | "\n" | |
1826 | "For example, the following adds a list of numbers, the calls\n" | |
1827 | "made to @code{+} are shown. (Of course @code{+} accepts\n" | |
1828 | "multiple arguments and can add a list directly, with\n" | |
1829 | "@code{apply}.)\n" | |
1830 | "\n" | |
1831 | "@example\n" | |
1832 | "(reduce-right + 0 '(5 6 7)) @result{} 18\n" | |
1833 | "\n" | |
1834 | "(+ 6 7) @result{} 13\n" | |
1835 | "(+ 5 13) @result{} 18\n" | |
1836 | "@end example\n" | |
1837 | "\n" | |
1838 | "@code{reduce-right} can be used instead of @code{fold-right}\n" | |
1839 | "where the @var{init} value is an ``identity'', meaning a value\n" | |
1840 | "which under @var{proc} doesn't change the result, in this case\n" | |
1841 | "0 is an identity since @code{(+ 7 0)} is just 5.\n" | |
1842 | "@code{reduce-right} avoids that unnecessary call.\n" | |
1843 | "\n" | |
1844 | "@code{reduce} should be preferred over @code{reduce-right} if\n" | |
1845 | "the order of processing doesn't matter, or can be arranged\n" | |
1846 | "either way, since @code{reduce} is a little more efficient.") | |
1847 | #define FUNC_NAME s_scm_srfi1_reduce_right | |
1848 | { | |
1849 | /* To work backwards across a list requires either repeatedly traversing | |
1850 | to get each previous element, or using some memory for a reversed or | |
1851 | random-access form. Repeated traversal might not be too terrible, but | |
1852 | is of course quadratic complexity and hence to be avoided in case LST | |
1853 | is long. A vector is preferred over a reversed list since it's more | |
1854 | compact and is less work for the gc to collect. */ | |
1855 | ||
1856 | scm_t_trampoline_2 proc_tramp = scm_trampoline_2 (proc); | |
1857 | SCM ret, vec; | |
1858 | long len, i; | |
1859 | ||
1860 | SCM_ASSERT (proc_tramp, proc, SCM_ARG1, FUNC_NAME); | |
1861 | ||
1862 | if (SCM_NULL_OR_NIL_P (lst)) | |
1863 | return def; | |
1864 | ||
1865 | vec = scm_vector (lst); | |
1866 | len = SCM_SIMPLE_VECTOR_LENGTH (vec); | |
1867 | ||
1868 | ret = SCM_SIMPLE_VECTOR_REF (vec, len-1); | |
1869 | for (i = len-2; i >= 0; i--) | |
1870 | ret = proc_tramp (proc, SCM_SIMPLE_VECTOR_REF (vec, i), ret); | |
1871 | ||
1872 | return ret; | |
1873 | } | |
1874 | #undef FUNC_NAME | |
1875 | ||
1876 | ||
59747b8d KR |
1877 | SCM_DEFINE (scm_srfi1_remove, "remove", 2, 0, 0, |
1878 | (SCM pred, SCM list), | |
1879 | "Return a list containing all elements from @var{lst} which do\n" | |
1880 | "not satisfy the predicate @var{pred}. The elements in the\n" | |
1881 | "result list have the same order as in @var{lst}. The order in\n" | |
1882 | "which @var{pred} is applied to the list elements is not\n" | |
1883 | "specified.") | |
1884 | #define FUNC_NAME s_scm_srfi1_remove | |
1885 | { | |
1886 | scm_t_trampoline_1 call = scm_trampoline_1 (pred); | |
1887 | SCM walk; | |
1888 | SCM *prev; | |
1889 | SCM res = SCM_EOL; | |
1890 | SCM_ASSERT (call, pred, 1, FUNC_NAME); | |
1891 | SCM_VALIDATE_LIST (2, list); | |
1892 | ||
1893 | for (prev = &res, walk = list; | |
1894 | scm_is_pair (walk); | |
1895 | walk = SCM_CDR (walk)) | |
1896 | { | |
1897 | if (scm_is_false (call (pred, SCM_CAR (walk)))) | |
1898 | { | |
1899 | *prev = scm_cons (SCM_CAR (walk), SCM_EOL); | |
1900 | prev = SCM_CDRLOC (*prev); | |
1901 | } | |
1902 | } | |
1903 | ||
1904 | return res; | |
1905 | } | |
1906 | #undef FUNC_NAME | |
1907 | ||
2b077051 KR |
1908 | |
1909 | SCM_DEFINE (scm_srfi1_remove_x, "remove!", 2, 0, 0, | |
1910 | (SCM pred, SCM list), | |
1911 | "Return a list containing all elements from @var{list} which do\n" | |
1912 | "not satisfy the predicate @var{pred}. The elements in the\n" | |
1913 | "result list have the same order as in @var{list}. The order in\n" | |
1914 | "which @var{pred} is applied to the list elements is not\n" | |
1915 | "specified. @var{list} may be modified to build the return\n" | |
1916 | "list.") | |
1917 | #define FUNC_NAME s_scm_srfi1_remove_x | |
1918 | { | |
1919 | scm_t_trampoline_1 call = scm_trampoline_1 (pred); | |
1920 | SCM walk; | |
1921 | SCM *prev; | |
1922 | SCM_ASSERT (call, pred, 1, FUNC_NAME); | |
1923 | SCM_VALIDATE_LIST (2, list); | |
1924 | ||
1925 | for (prev = &list, walk = list; | |
1926 | scm_is_pair (walk); | |
1927 | walk = SCM_CDR (walk)) | |
1928 | { | |
1929 | if (scm_is_false (call (pred, SCM_CAR (walk)))) | |
1930 | prev = SCM_CDRLOC (walk); | |
1931 | else | |
1932 | *prev = SCM_CDR (walk); | |
1933 | } | |
1934 | ||
1935 | return list; | |
1936 | } | |
1937 | #undef FUNC_NAME | |
1938 | ||
1939 | ||
03731332 KR |
1940 | SCM_DEFINE (scm_srfi1_seventh, "seventh", 1, 0, 0, |
1941 | (SCM lst), | |
1942 | "Return the seventh element of @var{lst}.") | |
1943 | #define FUNC_NAME s_scm_srfi1_seventh | |
1944 | { | |
b730fbf1 | 1945 | return scm_list_ref (lst, scm_from_int (6)); |
03731332 KR |
1946 | } |
1947 | #undef FUNC_NAME | |
1948 | ||
1949 | ||
1950 | SCM_DEFINE (scm_srfi1_sixth, "sixth", 1, 0, 0, | |
1951 | (SCM lst), | |
1952 | "Return the sixth element of @var{lst}.") | |
1953 | #define FUNC_NAME s_scm_srfi1_sixth | |
1954 | { | |
b730fbf1 | 1955 | return scm_list_ref (lst, scm_from_int (5)); |
03731332 KR |
1956 | } |
1957 | #undef FUNC_NAME | |
1958 | ||
1959 | ||
597dbd4e KR |
1960 | SCM_DEFINE (scm_srfi1_span, "span", 2, 0, 0, |
1961 | (SCM pred, SCM lst), | |
1962 | "Return two values, the longest initial prefix of @var{lst}\n" | |
1963 | "whose elements all satisfy the predicate @var{pred}, and the\n" | |
1964 | "remainder of @var{lst}.") | |
1965 | #define FUNC_NAME s_scm_srfi1_span | |
1966 | { | |
1967 | scm_t_trampoline_1 pred_tramp; | |
1968 | SCM ret, *p; | |
1969 | ||
1970 | pred_tramp = scm_trampoline_1 (pred); | |
1971 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
1972 | ||
1973 | ret = SCM_EOL; | |
1974 | p = &ret; | |
1975 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) | |
1976 | { | |
1977 | SCM elem = SCM_CAR (lst); | |
1978 | if (scm_is_false (pred_tramp (pred, elem))) | |
1979 | goto done; | |
1980 | ||
1981 | /* want this elem, tack it onto the end of ret */ | |
1982 | *p = scm_cons (elem, SCM_EOL); | |
1983 | p = SCM_CDRLOC (*p); | |
1984 | } | |
1985 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG2, FUNC_NAME, "list"); | |
1986 | ||
1987 | done: | |
1988 | return scm_values (scm_list_2 (ret, lst)); | |
1989 | } | |
1990 | #undef FUNC_NAME | |
1991 | ||
1992 | ||
1993 | SCM_DEFINE (scm_srfi1_span_x, "span!", 2, 0, 0, | |
1994 | (SCM pred, SCM lst), | |
1995 | "Return two values, the longest initial prefix of @var{lst}\n" | |
1996 | "whose elements all satisfy the predicate @var{pred}, and the\n" | |
1997 | "remainder of @var{lst}. @var{lst} may be modified to form the\n" | |
1998 | "return.") | |
1999 | #define FUNC_NAME s_scm_srfi1_span_x | |
2000 | { | |
2001 | SCM upto, *p; | |
2002 | scm_t_trampoline_1 pred_tramp; | |
2003 | ||
2004 | pred_tramp = scm_trampoline_1 (pred); | |
2005 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
2006 | ||
2007 | p = &lst; | |
2008 | for (upto = lst; scm_is_pair (upto); upto = SCM_CDR (upto)) | |
2009 | { | |
2010 | if (scm_is_false (pred_tramp (pred, SCM_CAR (upto)))) | |
2011 | goto done; | |
2012 | ||
2013 | /* want this element */ | |
2014 | p = SCM_CDRLOC (upto); | |
2015 | } | |
2016 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (upto), lst, SCM_ARG2, FUNC_NAME, "list"); | |
2017 | ||
2018 | done: | |
2019 | *p = SCM_EOL; | |
2020 | return scm_values (scm_list_2 (lst, upto)); | |
2021 | } | |
2022 | #undef FUNC_NAME | |
2023 | ||
2024 | ||
d2f57ee0 KR |
2025 | SCM_DEFINE (scm_srfi1_split_at, "split-at", 2, 0, 0, |
2026 | (SCM lst, SCM n), | |
2027 | "Return two values (multiple values), being a list of the\n" | |
2028 | "elements before index @var{n} in @var{lst}, and a list of those\n" | |
2029 | "after.") | |
2030 | #define FUNC_NAME s_scm_srfi1_split_at | |
2031 | { | |
2032 | size_t nn; | |
2033 | /* pre is a list of elements before the i split point, loc is the CDRLOC | |
2034 | of the last cell, ie. where to store to append to it */ | |
2035 | SCM pre = SCM_EOL; | |
2036 | SCM *loc = ⪯ | |
2037 | ||
2038 | for (nn = scm_to_size_t (n); nn != 0; nn--) | |
2039 | { | |
2040 | SCM_VALIDATE_CONS (SCM_ARG1, lst); | |
2041 | ||
2042 | *loc = scm_cons (SCM_CAR (lst), SCM_EOL); | |
2043 | loc = SCM_CDRLOC (*loc); | |
2044 | lst = SCM_CDR(lst); | |
2045 | } | |
2046 | return scm_values (scm_list_2 (pre, lst)); | |
2047 | } | |
2048 | #undef FUNC_NAME | |
2049 | ||
2050 | ||
2051 | SCM_DEFINE (scm_srfi1_split_at_x, "split-at!", 2, 0, 0, | |
2052 | (SCM lst, SCM n), | |
2053 | "Return two values (multiple values), being a list of the\n" | |
2054 | "elements before index @var{n} in @var{lst}, and a list of those\n" | |
2055 | "after. @var{lst} is modified to form those values.") | |
2056 | #define FUNC_NAME s_scm_srfi1_split_at | |
2057 | { | |
2058 | size_t nn; | |
2059 | SCM upto = lst; | |
2060 | SCM *loc = &lst; | |
2061 | ||
2062 | for (nn = scm_to_size_t (n); nn != 0; nn--) | |
2063 | { | |
2064 | SCM_VALIDATE_CONS (SCM_ARG1, upto); | |
2065 | ||
2066 | loc = SCM_CDRLOC (upto); | |
2067 | upto = SCM_CDR (upto); | |
2068 | } | |
2069 | ||
2070 | *loc = SCM_EOL; | |
2071 | return scm_values (scm_list_2 (lst, upto)); | |
2072 | } | |
2073 | #undef FUNC_NAME | |
2074 | ||
2075 | ||
597dbd4e KR |
2076 | SCM_DEFINE (scm_srfi1_take_x, "take!", 2, 0, 0, |
2077 | (SCM lst, SCM n), | |
2078 | "Return a list containing the first @var{n} elements of\n" | |
2079 | "@var{lst}.") | |
2080 | #define FUNC_NAME s_scm_srfi1_take_x | |
2081 | { | |
2082 | long nn; | |
2083 | SCM pos; | |
2084 | ||
b730fbf1 | 2085 | nn = scm_to_signed_integer (n, 0, LONG_MAX); |
597dbd4e KR |
2086 | if (nn == 0) |
2087 | return SCM_EOL; | |
2088 | ||
b730fbf1 | 2089 | pos = scm_list_tail (lst, scm_from_long (nn - 1)); |
597dbd4e KR |
2090 | |
2091 | /* Must have at least one cell left, mustn't have reached the end of an | |
2092 | n-1 element list. SCM_VALIDATE_CONS here gives the same error as | |
2093 | scm_list_tail does on say an n-2 element list, though perhaps a range | |
2094 | error would make more sense (for both). */ | |
2095 | SCM_VALIDATE_CONS (SCM_ARG1, pos); | |
2096 | ||
2097 | SCM_SETCDR (pos, SCM_EOL); | |
2098 | return lst; | |
2099 | } | |
2100 | #undef FUNC_NAME | |
2101 | ||
2102 | ||
2b077051 KR |
2103 | SCM_DEFINE (scm_srfi1_take_right, "take-right", 2, 0, 0, |
2104 | (SCM lst, SCM n), | |
2105 | "Return the a list containing the @var{n} last elements of\n" | |
2106 | "@var{lst}.") | |
2107 | #define FUNC_NAME s_scm_srfi1_take_right | |
2108 | { | |
2109 | SCM tail = scm_list_tail (lst, n); | |
2110 | while (scm_is_pair (tail)) | |
2111 | { | |
2112 | lst = SCM_CDR (lst); | |
2113 | tail = SCM_CDR (tail); | |
2114 | } | |
2115 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P(tail), tail, SCM_ARG1, FUNC_NAME, "list"); | |
2116 | return lst; | |
2117 | } | |
2118 | #undef FUNC_NAME | |
2119 | ||
2120 | ||
597dbd4e KR |
2121 | SCM_DEFINE (scm_srfi1_take_while, "take-while", 2, 0, 0, |
2122 | (SCM pred, SCM lst), | |
2123 | "Return a new list which is the longest initial prefix of\n" | |
2124 | "@var{lst} whose elements all satisfy the predicate @var{pred}.") | |
2125 | #define FUNC_NAME s_scm_srfi1_take_while | |
2126 | { | |
2127 | scm_t_trampoline_1 pred_tramp; | |
2128 | SCM ret, *p; | |
2129 | ||
2130 | pred_tramp = scm_trampoline_1 (pred); | |
2131 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
2132 | ||
2133 | ret = SCM_EOL; | |
2134 | p = &ret; | |
2135 | for ( ; scm_is_pair (lst); lst = SCM_CDR (lst)) | |
2136 | { | |
2137 | SCM elem = SCM_CAR (lst); | |
2138 | if (scm_is_false (pred_tramp (pred, elem))) | |
2139 | goto done; | |
2140 | ||
2141 | /* want this elem, tack it onto the end of ret */ | |
2142 | *p = scm_cons (elem, SCM_EOL); | |
2143 | p = SCM_CDRLOC (*p); | |
2144 | } | |
2145 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (lst), lst, SCM_ARG2, FUNC_NAME, "list"); | |
2146 | ||
2147 | done: | |
2148 | return ret; | |
2149 | } | |
2150 | #undef FUNC_NAME | |
2151 | ||
2152 | ||
2153 | SCM_DEFINE (scm_srfi1_take_while_x, "take-while!", 2, 0, 0, | |
2154 | (SCM pred, SCM lst), | |
2155 | "Return the longest initial prefix of @var{lst} whose elements\n" | |
2156 | "all satisfy the predicate @var{pred}. @var{lst} may be\n" | |
2157 | "modified to form the return.") | |
2158 | #define FUNC_NAME s_scm_srfi1_take_while_x | |
2159 | { | |
2160 | SCM upto, *p; | |
2161 | scm_t_trampoline_1 pred_tramp; | |
2162 | ||
2163 | pred_tramp = scm_trampoline_1 (pred); | |
2164 | SCM_ASSERT (pred_tramp, pred, SCM_ARG1, FUNC_NAME); | |
2165 | ||
2166 | p = &lst; | |
2167 | for (upto = lst; scm_is_pair (upto); upto = SCM_CDR (upto)) | |
2168 | { | |
2169 | if (scm_is_false (pred_tramp (pred, SCM_CAR (upto)))) | |
2170 | goto done; | |
2171 | ||
2172 | /* want this element */ | |
2173 | p = SCM_CDRLOC (upto); | |
2174 | } | |
2175 | SCM_ASSERT_TYPE (SCM_NULL_OR_NIL_P (upto), lst, SCM_ARG2, FUNC_NAME, "list"); | |
2176 | ||
2177 | done: | |
2178 | *p = SCM_EOL; | |
2179 | return lst; | |
2180 | } | |
2181 | #undef FUNC_NAME | |
2182 | ||
2183 | ||
03731332 KR |
2184 | SCM_DEFINE (scm_srfi1_tenth, "tenth", 1, 0, 0, |
2185 | (SCM lst), | |
2186 | "Return the tenth element of @var{lst}.") | |
2187 | #define FUNC_NAME s_scm_srfi1_tenth | |
2188 | { | |
b730fbf1 | 2189 | return scm_list_ref (lst, scm_from_int (9)); |
03731332 KR |
2190 | } |
2191 | #undef FUNC_NAME | |
2192 | ||
2193 | ||
e556f8c3 KR |
2194 | SCM_DEFINE (scm_srfi1_xcons, "xcons", 2, 0, 0, |
2195 | (SCM d, SCM a), | |
2196 | "Like @code{cons}, but with interchanged arguments. Useful\n" | |
2197 | "mostly when passed to higher-order procedures.") | |
2198 | #define FUNC_NAME s_scm_srfi1_xcons | |
2199 | { | |
2200 | return scm_cons (a, d); | |
2201 | } | |
2202 | #undef FUNC_NAME | |
2203 | ||
2204 | ||
ee6aac97 MD |
2205 | void |
2206 | scm_init_srfi_1 (void) | |
2207 | { | |
a48d60b1 | 2208 | SCM the_root_module = scm_lookup_closure_module (SCM_BOOL_F); |
ee6aac97 MD |
2209 | #ifndef SCM_MAGIC_SNARFER |
2210 | #include "srfi/srfi-1.x" | |
2211 | #endif | |
a48d60b1 MD |
2212 | scm_c_extend_primitive_generic |
2213 | (SCM_VARIABLE_REF (scm_c_module_lookup (the_root_module, "map")), | |
2214 | SCM_VARIABLE_REF (scm_c_lookup ("map"))); | |
2215 | scm_c_extend_primitive_generic | |
2216 | (SCM_VARIABLE_REF (scm_c_module_lookup (the_root_module, "for-each")), | |
2217 | SCM_VARIABLE_REF (scm_c_lookup ("for-each"))); | |
ee6aac97 MD |
2218 | } |
2219 | ||
2220 | /* End of srfi-1.c. */ |