Commit | Line | Data |
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6c9e8a53 | 1 | /* Copyright (C) 1995,1996,1997,2000,2001,2003,2004,2008,2009 |
212e58ed | 2 | * Free Software Foundation, Inc. |
0f2d19dd | 3 | * |
73be1d9e | 4 | * This library is free software; you can redistribute it and/or |
53befeb7 NJ |
5 | * modify it under the terms of the GNU Lesser General Public License |
6 | * as published by the Free Software Foundation; either version 3 of | |
7 | * the License, or (at your option) any later version. | |
0f2d19dd | 8 | * |
53befeb7 NJ |
9 | * This library is distributed in the hope that it will be useful, but |
10 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
73be1d9e MV |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | * Lesser General Public License for more details. | |
0f2d19dd | 13 | * |
73be1d9e MV |
14 | * You should have received a copy of the GNU Lesser General Public |
15 | * License along with this library; if not, write to the Free Software | |
53befeb7 NJ |
16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
17 | * 02110-1301 USA | |
73be1d9e | 18 | */ |
1bbd0b84 | 19 | |
1bbd0b84 | 20 | |
0f2d19dd | 21 | \f |
dbb605f5 LC |
22 | #ifdef HAVE_CONFIG_H |
23 | # include <config.h> | |
24 | #endif | |
25 | ||
a0599745 MD |
26 | #include "libguile/_scm.h" |
27 | #include "libguile/eq.h" | |
c96d76b8 | 28 | #include "libguile/lang.h" |
20e6290e | 29 | |
a0599745 MD |
30 | #include "libguile/validate.h" |
31 | #include "libguile/list.h" | |
c614a00b | 32 | #include "libguile/eval.h" |
0f2d19dd | 33 | |
0f2d19dd | 34 | #include <stdarg.h> |
0f2d19dd JB |
35 | |
36 | \f | |
df13742c | 37 | /* creating lists */ |
0f2d19dd | 38 | |
34d19ef6 | 39 | #define SCM_I_CONS(cell, x, y) \ |
1afff620 | 40 | do { \ |
228a24ef | 41 | cell = scm_cell ((scm_t_bits)x, (scm_t_bits)y); \ |
1afff620 KN |
42 | } while (0) |
43 | ||
44 | SCM | |
45 | scm_list_1 (SCM e1) | |
46 | { | |
47 | SCM c1; | |
48 | SCM_I_CONS (c1, e1, SCM_EOL); | |
49 | return c1; | |
50 | } | |
51 | ||
52 | SCM | |
53 | scm_list_2 (SCM e1, SCM e2) | |
54 | { | |
55 | SCM c1, c2; | |
56 | SCM_I_CONS (c2, e2, SCM_EOL); | |
57 | SCM_I_CONS (c1, e1, c2); | |
58 | return c1; | |
59 | } | |
60 | ||
61 | SCM | |
62 | scm_list_3 (SCM e1, SCM e2, SCM e3) | |
63 | { | |
64 | SCM c1, c2, c3; | |
65 | SCM_I_CONS (c3, e3, SCM_EOL); | |
66 | SCM_I_CONS (c2, e2, c3); | |
67 | SCM_I_CONS (c1, e1, c2); | |
68 | return c1; | |
69 | } | |
70 | ||
71 | SCM | |
72 | scm_list_4 (SCM e1, SCM e2, SCM e3, SCM e4) | |
73 | { | |
74 | return scm_cons2 (e1, e2, scm_list_2 (e3, e4)); | |
75 | } | |
76 | ||
77 | SCM | |
78 | scm_list_5 (SCM e1, SCM e2, SCM e3, SCM e4, SCM e5) | |
79 | { | |
80 | return scm_cons2 (e1, e2, scm_list_3 (e3, e4, e5)); | |
81 | } | |
82 | ||
0f2d19dd | 83 | SCM |
1afff620 | 84 | scm_list_n (SCM elt, ...) |
0f2d19dd JB |
85 | { |
86 | va_list foo; | |
2de14ecd GB |
87 | SCM answer = SCM_EOL; |
88 | SCM *pos = &answer; | |
0f2d19dd | 89 | |
0dbfb25a | 90 | va_start (foo, elt); |
fbd485ba | 91 | while (! SCM_UNBNDP (elt)) |
0f2d19dd | 92 | { |
1e55d288 | 93 | #if (SCM_DEBUG_CELL_ACCESSES == 1) |
eb741d98 HWN |
94 | if (SCM_NIMP (elt)) |
95 | SCM_VALIDATE_CELL(elt, 0); | |
1e55d288 | 96 | #endif |
0f2d19dd | 97 | *pos = scm_cons (elt, SCM_EOL); |
25d8012c | 98 | pos = SCM_CDRLOC (*pos); |
0f2d19dd JB |
99 | elt = va_arg (foo, SCM); |
100 | } | |
de90ef0f | 101 | va_end (foo); |
0f2d19dd JB |
102 | return answer; |
103 | } | |
104 | ||
105 | ||
2ac6b60e KR |
106 | SCM_DEFINE (scm_make_list, "make-list", 1, 1, 0, |
107 | (SCM n, SCM init), | |
108 | "Create a list containing of @var{n} elements, where each\n" | |
109 | "element is initialized to @var{init}. @var{init} defaults to\n" | |
110 | "the empty list @code{()} if not given.") | |
661ae7ab | 111 | #define FUNC_NAME s_scm_make_list |
2ac6b60e KR |
112 | { |
113 | unsigned nn = scm_to_uint (n); | |
114 | unsigned i; | |
115 | SCM ret = SCM_EOL; | |
116 | ||
117 | if (SCM_UNBNDP (init)) | |
118 | init = SCM_EOL; | |
119 | ||
120 | for (i = 0; i < nn; i++) | |
121 | ret = scm_cons (init, ret); | |
122 | return ret; | |
123 | } | |
124 | #undef FUNC_NAME | |
125 | ||
126 | ||
b906b056 | 127 | SCM_DEFINE (scm_cons_star, "cons*", 1, 0, 1, |
1bbd0b84 | 128 | (SCM arg, SCM rest), |
5352393c MG |
129 | "Like @code{list}, but the last arg provides the tail of the\n" |
130 | "constructed list, returning @code{(cons @var{arg1} (cons\n" | |
a17bb5fd | 131 | "@var{arg2} (cons @dots{} @var{argn})))}. Requires at least one\n" |
5352393c MG |
132 | "argument. If given one argument, that argument is returned as\n" |
133 | "result. This function is called @code{list*} in some other\n" | |
134 | "Schemes and in Common LISP.") | |
26a379b2 | 135 | #define FUNC_NAME s_scm_cons_star |
a610b8d9 | 136 | { |
b906b056 KR |
137 | SCM ret = SCM_EOL; |
138 | SCM *p = &ret; | |
139 | ||
af45e3b0 | 140 | SCM_VALIDATE_REST_ARGUMENT (rest); |
b906b056 KR |
141 | |
142 | for ( ; scm_is_pair (rest); rest = SCM_CDR (rest)) | |
a610b8d9 | 143 | { |
b906b056 KR |
144 | *p = scm_cons (arg, SCM_EOL); |
145 | p = SCM_CDRLOC (*p); | |
146 | arg = SCM_CAR (rest); | |
a610b8d9 | 147 | } |
b906b056 KR |
148 | |
149 | *p = arg; | |
150 | return ret; | |
a610b8d9 | 151 | } |
1bbd0b84 | 152 | #undef FUNC_NAME |
a610b8d9 | 153 | |
0f2d19dd JB |
154 | |
155 | \f | |
df13742c | 156 | /* general questions about lists --- null?, list?, length, etc. */ |
0f2d19dd | 157 | |
3b3b36dd | 158 | SCM_DEFINE (scm_null_p, "null?", 1, 0, 0, |
1bbd0b84 | 159 | (SCM x), |
5352393c | 160 | "Return @code{#t} iff @var{x} is the empty list, else @code{#f}.") |
1bbd0b84 | 161 | #define FUNC_NAME s_scm_null_p |
0f2d19dd | 162 | { |
7888309b | 163 | return scm_from_bool (SCM_NULL_OR_NIL_P (x)); |
0f2d19dd | 164 | } |
1bbd0b84 | 165 | #undef FUNC_NAME |
0f2d19dd | 166 | |
2de14ecd | 167 | |
3b3b36dd | 168 | SCM_DEFINE (scm_list_p, "list?", 1, 0, 0, |
1bbd0b84 | 169 | (SCM x), |
5352393c | 170 | "Return @code{#t} iff @var{x} is a proper list, else @code{#f}.") |
1bbd0b84 | 171 | #define FUNC_NAME s_scm_list_p |
0f2d19dd | 172 | { |
7888309b | 173 | return scm_from_bool (scm_ilength (x) >= 0); |
0f2d19dd | 174 | } |
1bbd0b84 | 175 | #undef FUNC_NAME |
0f2d19dd JB |
176 | |
177 | ||
df13742c | 178 | /* Return the length of SX, or -1 if it's not a proper list. |
448a3bc2 | 179 | This uses the "tortoise and hare" algorithm to detect "infinitely |
df13742c JB |
180 | long" lists (i.e. lists with cycles in their cdrs), and returns -1 |
181 | if it does find one. */ | |
c014a02e ML |
182 | long |
183 | scm_ilength(SCM sx) | |
0f2d19dd | 184 | { |
c014a02e | 185 | long i = 0; |
e1385ffc GB |
186 | SCM tortoise = sx; |
187 | SCM hare = sx; | |
df13742c | 188 | |
0f2d19dd | 189 | do { |
c96d76b8 | 190 | if (SCM_NULL_OR_NIL_P(hare)) return i; |
d2e53ed6 | 191 | if (!scm_is_pair (hare)) return -1; |
df13742c | 192 | hare = SCM_CDR(hare); |
0f2d19dd | 193 | i++; |
c96d76b8 | 194 | if (SCM_NULL_OR_NIL_P(hare)) return i; |
d2e53ed6 | 195 | if (!scm_is_pair (hare)) return -1; |
df13742c | 196 | hare = SCM_CDR(hare); |
0f2d19dd | 197 | i++; |
448a3bc2 JB |
198 | /* For every two steps the hare takes, the tortoise takes one. */ |
199 | tortoise = SCM_CDR(tortoise); | |
0f2d19dd | 200 | } |
bc36d050 | 201 | while (!scm_is_eq (hare, tortoise)); |
df13742c | 202 | |
448a3bc2 | 203 | /* If the tortoise ever catches the hare, then the list must contain |
df13742c | 204 | a cycle. */ |
0f2d19dd JB |
205 | return -1; |
206 | } | |
207 | ||
2de14ecd | 208 | |
3b3b36dd | 209 | SCM_DEFINE (scm_length, "length", 1, 0, 0, |
1bbd0b84 | 210 | (SCM lst), |
5352393c | 211 | "Return the number of elements in list @var{lst}.") |
1bbd0b84 | 212 | #define FUNC_NAME s_scm_length |
0f2d19dd | 213 | { |
c014a02e | 214 | long i; |
34d19ef6 | 215 | SCM_VALIDATE_LIST_COPYLEN (1, lst, i); |
e11e83f3 | 216 | return scm_from_long (i); |
0f2d19dd | 217 | } |
1bbd0b84 | 218 | #undef FUNC_NAME |
0f2d19dd JB |
219 | |
220 | ||
221 | \f | |
df13742c | 222 | /* appending lists */ |
0f2d19dd | 223 | |
a1ec6916 | 224 | SCM_DEFINE (scm_append, "append", 0, 0, 1, |
1bbd0b84 | 225 | (SCM args), |
5352393c MG |
226 | "Return a list consisting of the elements the lists passed as\n" |
227 | "arguments.\n" | |
1e6808ea | 228 | "@lisp\n" |
5352393c MG |
229 | "(append '(x) '(y)) @result{} (x y)\n" |
230 | "(append '(a) '(b c d)) @result{} (a b c d)\n" | |
231 | "(append '(a (b)) '((c))) @result{} (a (b) (c))\n" | |
1e6808ea | 232 | "@end lisp\n" |
5352393c MG |
233 | "The resulting list is always newly allocated, except that it\n" |
234 | "shares structure with the last list argument. The last\n" | |
235 | "argument may actually be any object; an improper list results\n" | |
236 | "if the last argument is not a proper list.\n" | |
1e6808ea | 237 | "@lisp\n" |
5352393c MG |
238 | "(append '(a b) '(c . d)) @result{} (a b c . d)\n" |
239 | "(append '() 'a) @result{} a\n" | |
1e6808ea | 240 | "@end lisp") |
1bbd0b84 | 241 | #define FUNC_NAME s_scm_append |
0f2d19dd | 242 | { |
af45e3b0 | 243 | SCM_VALIDATE_REST_ARGUMENT (args); |
d2e53ed6 | 244 | if (scm_is_null (args)) { |
af45e3b0 DH |
245 | return SCM_EOL; |
246 | } else { | |
247 | SCM res = SCM_EOL; | |
248 | SCM *lloc = &res; | |
249 | SCM arg = SCM_CAR (args); | |
4c13270f | 250 | int argnum = 1; |
af45e3b0 | 251 | args = SCM_CDR (args); |
d2e53ed6 MV |
252 | while (!scm_is_null (args)) { |
253 | while (scm_is_pair (arg)) { | |
af45e3b0 DH |
254 | *lloc = scm_cons (SCM_CAR (arg), SCM_EOL); |
255 | lloc = SCM_CDRLOC (*lloc); | |
256 | arg = SCM_CDR (arg); | |
257 | } | |
4c13270f | 258 | SCM_VALIDATE_NULL_OR_NIL (argnum, arg); |
af45e3b0 DH |
259 | arg = SCM_CAR (args); |
260 | args = SCM_CDR (args); | |
4c13270f | 261 | argnum++; |
af45e3b0 DH |
262 | }; |
263 | *lloc = arg; | |
0f2d19dd JB |
264 | return res; |
265 | } | |
0f2d19dd | 266 | } |
1bbd0b84 | 267 | #undef FUNC_NAME |
0f2d19dd JB |
268 | |
269 | ||
a1ec6916 | 270 | SCM_DEFINE (scm_append_x, "append!", 0, 0, 1, |
1e6808ea MG |
271 | (SCM lists), |
272 | "A destructive version of @code{append} (@pxref{Pairs and\n" | |
7a095584 | 273 | "Lists,,,r5rs, The Revised^5 Report on Scheme}). The cdr field\n" |
1e6808ea | 274 | "of each list's final pair is changed to point to the head of\n" |
71a89639 | 275 | "the next list, so no consing is performed. Return\n" |
1e6808ea | 276 | "the mutated list.") |
1bbd0b84 | 277 | #define FUNC_NAME s_scm_append_x |
0f2d19dd | 278 | { |
d4641098 | 279 | SCM ret, *loc; |
1e6808ea | 280 | SCM_VALIDATE_REST_ARGUMENT (lists); |
d4641098 | 281 | |
d2e53ed6 | 282 | if (scm_is_null (lists)) |
d4641098 KR |
283 | return SCM_EOL; |
284 | ||
285 | loc = &ret; | |
286 | for (;;) | |
287 | { | |
1e6808ea | 288 | SCM arg = SCM_CAR (lists); |
d4641098 KR |
289 | *loc = arg; |
290 | ||
1e6808ea | 291 | lists = SCM_CDR (lists); |
d2e53ed6 | 292 | if (scm_is_null (lists)) |
d4641098 KR |
293 | return ret; |
294 | ||
295 | if (!SCM_NULL_OR_NIL_P (arg)) | |
296 | { | |
297 | SCM_VALIDATE_CONS (SCM_ARG1, arg); | |
298 | loc = SCM_CDRLOC (scm_last_pair (arg)); | |
299 | } | |
af45e3b0 | 300 | } |
0f2d19dd | 301 | } |
1bbd0b84 | 302 | #undef FUNC_NAME |
0f2d19dd JB |
303 | |
304 | ||
3b3b36dd | 305 | SCM_DEFINE (scm_last_pair, "last-pair", 1, 0, 0, |
e1385ffc | 306 | (SCM lst), |
71a89639 | 307 | "Return the last pair in @var{lst}, signalling an error if\n" |
b380b885 | 308 | "@var{lst} is circular.") |
1bbd0b84 | 309 | #define FUNC_NAME s_scm_last_pair |
df13742c | 310 | { |
e1385ffc GB |
311 | SCM tortoise = lst; |
312 | SCM hare = lst; | |
0f2d19dd | 313 | |
c96d76b8 NJ |
314 | if (SCM_NULL_OR_NIL_P (lst)) |
315 | return lst; | |
df13742c | 316 | |
e1385ffc GB |
317 | SCM_VALIDATE_CONS (SCM_ARG1, lst); |
318 | do { | |
319 | SCM ahead = SCM_CDR(hare); | |
d2e53ed6 | 320 | if (!scm_is_pair (ahead)) return hare; |
e1385ffc GB |
321 | hare = ahead; |
322 | ahead = SCM_CDR(hare); | |
d2e53ed6 | 323 | if (!scm_is_pair (ahead)) return hare; |
e1385ffc GB |
324 | hare = ahead; |
325 | tortoise = SCM_CDR(tortoise); | |
df13742c | 326 | } |
bc36d050 | 327 | while (!scm_is_eq (hare, tortoise)); |
1afff620 | 328 | SCM_MISC_ERROR ("Circular structure in position 1: ~S", scm_list_1 (lst)); |
df13742c | 329 | } |
1bbd0b84 | 330 | #undef FUNC_NAME |
df13742c JB |
331 | |
332 | \f | |
333 | /* reversing lists */ | |
0f2d19dd | 334 | |
a1ec6916 | 335 | SCM_DEFINE (scm_reverse, "reverse", 1, 0, 0, |
e1385ffc | 336 | (SCM lst), |
5352393c MG |
337 | "Return a new list that contains the elements of @var{lst} but\n" |
338 | "in reverse order.") | |
e1385ffc GB |
339 | #define FUNC_NAME s_scm_reverse |
340 | { | |
341 | SCM result = SCM_EOL; | |
342 | SCM tortoise = lst; | |
343 | SCM hare = lst; | |
344 | ||
345 | do { | |
c96d76b8 | 346 | if (SCM_NULL_OR_NIL_P(hare)) return result; |
d2e53ed6 | 347 | SCM_ASSERT(scm_is_pair(hare), lst, 1, FUNC_NAME); |
e1385ffc GB |
348 | result = scm_cons (SCM_CAR (hare), result); |
349 | hare = SCM_CDR (hare); | |
c96d76b8 | 350 | if (SCM_NULL_OR_NIL_P(hare)) return result; |
d2e53ed6 | 351 | SCM_ASSERT(scm_is_pair(hare), lst, 1, FUNC_NAME); |
e1385ffc GB |
352 | result = scm_cons (SCM_CAR (hare), result); |
353 | hare = SCM_CDR (hare); | |
354 | tortoise = SCM_CDR (tortoise); | |
355 | } | |
bc36d050 | 356 | while (!scm_is_eq (hare, tortoise)); |
1afff620 | 357 | SCM_MISC_ERROR ("Circular structure in position 1: ~S", scm_list_1 (lst)); |
e1385ffc GB |
358 | } |
359 | #undef FUNC_NAME | |
360 | ||
361 | SCM_DEFINE (scm_reverse_x, "reverse!", 1, 1, 0, | |
362 | (SCM lst, SCM new_tail), | |
7a095584 NJ |
363 | "A destructive version of @code{reverse} (@pxref{Pairs and Lists,,,r5rs,\n" |
364 | "The Revised^5 Report on Scheme}). The cdr of each cell in @var{lst} is\n" | |
71a89639 MV |
365 | "modified to point to the previous list element. Return the\n" |
366 | "reversed list.\n\n" | |
b380b885 MD |
367 | "Caveat: because the list is modified in place, the tail of the original\n" |
368 | "list now becomes its head, and the head of the original list now becomes\n" | |
369 | "the tail. Therefore, the @var{lst} symbol to which the head of the\n" | |
370 | "original list was bound now points to the tail. To ensure that the head\n" | |
371 | "of the modified list is not lost, it is wise to save the return value of\n" | |
372 | "@code{reverse!}") | |
1bbd0b84 | 373 | #define FUNC_NAME s_scm_reverse_x |
0f2d19dd | 374 | { |
e39c3de4 | 375 | SCM_VALIDATE_LIST (1, lst); |
3946f0de MD |
376 | if (SCM_UNBNDP (new_tail)) |
377 | new_tail = SCM_EOL; | |
378 | else | |
e39c3de4 | 379 | SCM_VALIDATE_LIST (2, new_tail); |
0f2d19dd | 380 | |
c96d76b8 | 381 | while (!SCM_NULL_OR_NIL_P (lst)) |
3946f0de | 382 | { |
e1385ffc GB |
383 | SCM old_tail = SCM_CDR (lst); |
384 | SCM_SETCDR (lst, new_tail); | |
385 | new_tail = lst; | |
386 | lst = old_tail; | |
3946f0de MD |
387 | } |
388 | return new_tail; | |
0f2d19dd | 389 | } |
1bbd0b84 | 390 | #undef FUNC_NAME |
0f2d19dd | 391 | |
0f2d19dd | 392 | \f |
685c0d71 | 393 | |
df13742c | 394 | /* indexing lists by element number */ |
0f2d19dd | 395 | |
3b3b36dd | 396 | SCM_DEFINE (scm_list_ref, "list-ref", 2, 0, 0, |
685c0d71 | 397 | (SCM list, SCM k), |
5352393c | 398 | "Return the @var{k}th element from @var{list}.") |
1bbd0b84 GB |
399 | #define FUNC_NAME s_scm_list_ref |
400 | { | |
685c0d71 | 401 | SCM lst = list; |
c014a02e | 402 | unsigned long int i; |
a55c2b68 | 403 | i = scm_to_ulong (k); |
d2e53ed6 | 404 | while (scm_is_pair (lst)) { |
685c0d71 DH |
405 | if (i == 0) |
406 | return SCM_CAR (lst); | |
407 | else { | |
408 | --i; | |
409 | lst = SCM_CDR (lst); | |
410 | } | |
411 | }; | |
c96d76b8 | 412 | if (SCM_NULL_OR_NIL_P (lst)) |
685c0d71 DH |
413 | SCM_OUT_OF_RANGE (2, k); |
414 | else | |
415 | SCM_WRONG_TYPE_ARG (1, list); | |
0f2d19dd | 416 | } |
1bbd0b84 | 417 | #undef FUNC_NAME |
0f2d19dd | 418 | |
685c0d71 | 419 | |
3b3b36dd | 420 | SCM_DEFINE (scm_list_set_x, "list-set!", 3, 0, 0, |
685c0d71 DH |
421 | (SCM list, SCM k, SCM val), |
422 | "Set the @var{k}th element of @var{list} to @var{val}.") | |
1bbd0b84 GB |
423 | #define FUNC_NAME s_scm_list_set_x |
424 | { | |
685c0d71 | 425 | SCM lst = list; |
a55c2b68 | 426 | unsigned long int i = scm_to_ulong (k); |
d2e53ed6 | 427 | while (scm_is_pair (lst)) { |
685c0d71 DH |
428 | if (i == 0) { |
429 | SCM_SETCAR (lst, val); | |
430 | return val; | |
431 | } else { | |
432 | --i; | |
433 | lst = SCM_CDR (lst); | |
434 | } | |
435 | }; | |
c96d76b8 | 436 | if (SCM_NULL_OR_NIL_P (lst)) |
685c0d71 DH |
437 | SCM_OUT_OF_RANGE (2, k); |
438 | else | |
439 | SCM_WRONG_TYPE_ARG (1, list); | |
0f2d19dd | 440 | } |
1bbd0b84 | 441 | #undef FUNC_NAME |
0f2d19dd JB |
442 | |
443 | ||
1bbd0b84 GB |
444 | SCM_REGISTER_PROC(s_list_cdr_ref, "list-cdr-ref", 2, 0, 0, scm_list_tail); |
445 | ||
3b3b36dd | 446 | SCM_DEFINE (scm_list_tail, "list-tail", 2, 0, 0, |
1bbd0b84 | 447 | (SCM lst, SCM k), |
8f85c0c6 | 448 | "@deffnx {Scheme Procedure} list-cdr-ref lst k\n" |
b380b885 MD |
449 | "Return the \"tail\" of @var{lst} beginning with its @var{k}th element.\n" |
450 | "The first element of the list is considered to be element 0.\n\n" | |
872e0c72 | 451 | "@code{list-tail} and @code{list-cdr-ref} are identical. It may help to\n" |
b380b885 MD |
452 | "think of @code{list-cdr-ref} as accessing the @var{k}th cdr of the list,\n" |
453 | "or returning the results of cdring @var{k} times down @var{lst}.") | |
1bbd0b84 | 454 | #define FUNC_NAME s_scm_list_tail |
df13742c | 455 | { |
a55c2b68 | 456 | size_t i = scm_to_size_t (k); |
df13742c | 457 | while (i-- > 0) { |
34d19ef6 | 458 | SCM_VALIDATE_CONS (1, lst); |
df13742c JB |
459 | lst = SCM_CDR(lst); |
460 | } | |
461 | return lst; | |
462 | } | |
1bbd0b84 | 463 | #undef FUNC_NAME |
df13742c | 464 | |
0f2d19dd | 465 | |
3b3b36dd | 466 | SCM_DEFINE (scm_list_cdr_set_x, "list-cdr-set!", 3, 0, 0, |
685c0d71 DH |
467 | (SCM list, SCM k, SCM val), |
468 | "Set the @var{k}th cdr of @var{list} to @var{val}.") | |
1bbd0b84 GB |
469 | #define FUNC_NAME s_scm_list_cdr_set_x |
470 | { | |
685c0d71 | 471 | SCM lst = list; |
a55c2b68 | 472 | size_t i = scm_to_size_t (k); |
d2e53ed6 | 473 | while (scm_is_pair (lst)) { |
685c0d71 DH |
474 | if (i == 0) { |
475 | SCM_SETCDR (lst, val); | |
476 | return val; | |
477 | } else { | |
478 | --i; | |
479 | lst = SCM_CDR (lst); | |
480 | } | |
481 | }; | |
c96d76b8 | 482 | if (SCM_NULL_OR_NIL_P (lst)) |
685c0d71 DH |
483 | SCM_OUT_OF_RANGE (2, k); |
484 | else | |
485 | SCM_WRONG_TYPE_ARG (1, list); | |
0f2d19dd | 486 | } |
1bbd0b84 | 487 | #undef FUNC_NAME |
0f2d19dd JB |
488 | |
489 | ||
490 | \f | |
df13742c | 491 | /* copying lists, perhaps partially */ |
0f2d19dd | 492 | |
3b3b36dd | 493 | SCM_DEFINE (scm_list_head, "list-head", 2, 0, 0, |
1bbd0b84 | 494 | (SCM lst, SCM k), |
b380b885 MD |
495 | "Copy the first @var{k} elements from @var{lst} into a new list, and\n" |
496 | "return it.") | |
1bbd0b84 | 497 | #define FUNC_NAME s_scm_list_head |
0f2d19dd JB |
498 | { |
499 | SCM answer; | |
500 | SCM * pos; | |
a55c2b68 | 501 | size_t i = scm_to_size_t (k); |
0f2d19dd | 502 | |
0f2d19dd JB |
503 | answer = SCM_EOL; |
504 | pos = &answer; | |
0f2d19dd JB |
505 | while (i-- > 0) |
506 | { | |
34d19ef6 | 507 | SCM_VALIDATE_CONS (1, lst); |
0f2d19dd | 508 | *pos = scm_cons (SCM_CAR (lst), SCM_EOL); |
25d8012c | 509 | pos = SCM_CDRLOC (*pos); |
0f2d19dd JB |
510 | lst = SCM_CDR(lst); |
511 | } | |
512 | return answer; | |
513 | } | |
1bbd0b84 | 514 | #undef FUNC_NAME |
0f2d19dd JB |
515 | |
516 | ||
212e58ed DH |
517 | /* Copy a list which is known to be finite. The last pair may or may not have |
518 | * a '() in its cdr. That is, improper lists are accepted. */ | |
519 | SCM | |
520 | scm_i_finite_list_copy (SCM list) | |
521 | { | |
d2e53ed6 | 522 | if (!scm_is_pair (list)) |
212e58ed DH |
523 | { |
524 | return list; | |
525 | } | |
526 | else | |
527 | { | |
528 | SCM tail; | |
529 | const SCM result = tail = scm_list_1 (SCM_CAR (list)); | |
530 | list = SCM_CDR (list); | |
d2e53ed6 | 531 | while (scm_is_pair (list)) |
212e58ed DH |
532 | { |
533 | const SCM new_tail = scm_list_1 (SCM_CAR (list)); | |
534 | SCM_SETCDR (tail, new_tail); | |
535 | tail = new_tail; | |
536 | list = SCM_CDR (list); | |
537 | } | |
538 | SCM_SETCDR (tail, list); | |
539 | ||
540 | return result; | |
541 | } | |
542 | } | |
543 | ||
544 | ||
a1ec6916 | 545 | SCM_DEFINE (scm_list_copy, "list-copy", 1, 0, 0, |
1bbd0b84 | 546 | (SCM lst), |
b380b885 | 547 | "Return a (newly-created) copy of @var{lst}.") |
1bbd0b84 | 548 | #define FUNC_NAME s_scm_list_copy |
df13742c JB |
549 | { |
550 | SCM newlst; | |
551 | SCM * fill_here; | |
552 | SCM from_here; | |
553 | ||
5d6bb349 KN |
554 | SCM_VALIDATE_LIST (1, lst); |
555 | ||
df13742c JB |
556 | newlst = SCM_EOL; |
557 | fill_here = &newlst; | |
558 | from_here = lst; | |
559 | ||
d2e53ed6 | 560 | while (scm_is_pair (from_here)) |
df13742c JB |
561 | { |
562 | SCM c; | |
563 | c = scm_cons (SCM_CAR (from_here), SCM_CDR (from_here)); | |
564 | *fill_here = c; | |
25d8012c | 565 | fill_here = SCM_CDRLOC (c); |
df13742c JB |
566 | from_here = SCM_CDR (from_here); |
567 | } | |
568 | return newlst; | |
569 | } | |
1bbd0b84 | 570 | #undef FUNC_NAME |
df13742c | 571 | |
fad3aaf1 KR |
572 | |
573 | SCM_PROC (s_list, "list", 0, 0, 1, scm_list_copy); | |
123a1b62 | 574 | SCM_SNARF_DOCS (primitive, scm_list_copy, "list", (SCM objs), 0, 0, 1, |
fad3aaf1 KR |
575 | "Return a list containing @var{objs}, the arguments to\n" |
576 | "@code{list}.") | |
577 | ||
303bddc8 KR |
578 | /* This used to be the code for "list", but it's wrong when used via apply |
579 | (it should copy the list). It seems pretty unlikely anyone would have | |
580 | been using this from C code, since it's a no-op, but keep it for strict | |
581 | binary compatibility. */ | |
582 | SCM | |
583 | scm_list (SCM objs) | |
584 | { | |
585 | return objs; | |
586 | } | |
587 | ||
fad3aaf1 | 588 | |
0f2d19dd | 589 | \f |
df13742c JB |
590 | /* membership tests (memq, memv, etc.) */ |
591 | ||
79a3dafe DH |
592 | /* The function scm_c_memq returns the first sublist of list whose car is |
593 | * 'eq?' obj, where the sublists of list are the non-empty lists returned by | |
594 | * (list-tail list k) for k less than the length of list. If obj does not | |
1e6808ea | 595 | * occur in list, then #f (not the empty list) is returned. |
79a3dafe DH |
596 | * List must be a proper list, otherwise scm_c_memq may crash or loop |
597 | * endlessly. | |
598 | */ | |
599 | SCM | |
600 | scm_c_memq (SCM obj, SCM list) | |
601 | { | |
c96d76b8 | 602 | for (; !SCM_NULL_OR_NIL_P (list); list = SCM_CDR (list)) |
79a3dafe | 603 | { |
bc36d050 | 604 | if (scm_is_eq (SCM_CAR (list), obj)) |
79a3dafe DH |
605 | return list; |
606 | } | |
607 | return SCM_BOOL_F; | |
608 | } | |
609 | ||
610 | ||
3b3b36dd | 611 | SCM_DEFINE (scm_memq, "memq", 2, 0, 0, |
1bbd0b84 | 612 | (SCM x, SCM lst), |
5352393c MG |
613 | "Return the first sublist of @var{lst} whose car is @code{eq?}\n" |
614 | "to @var{x} where the sublists of @var{lst} are the non-empty\n" | |
615 | "lists returned by @code{(list-tail @var{lst} @var{k})} for\n" | |
616 | "@var{k} less than the length of @var{lst}. If @var{x} does not\n" | |
617 | "occur in @var{lst}, then @code{#f} (not the empty list) is\n" | |
618 | "returned.") | |
1bbd0b84 | 619 | #define FUNC_NAME s_scm_memq |
0f2d19dd | 620 | { |
daa6ba18 | 621 | SCM_VALIDATE_LIST (2, lst); |
79a3dafe | 622 | return scm_c_memq (x, lst); |
0f2d19dd | 623 | } |
1bbd0b84 | 624 | #undef FUNC_NAME |
0f2d19dd JB |
625 | |
626 | ||
3b3b36dd | 627 | SCM_DEFINE (scm_memv, "memv", 2, 0, 0, |
1bbd0b84 | 628 | (SCM x, SCM lst), |
5352393c MG |
629 | "Return the first sublist of @var{lst} whose car is @code{eqv?}\n" |
630 | "to @var{x} where the sublists of @var{lst} are the non-empty\n" | |
631 | "lists returned by @code{(list-tail @var{lst} @var{k})} for\n" | |
632 | "@var{k} less than the length of @var{lst}. If @var{x} does not\n" | |
633 | "occur in @var{lst}, then @code{#f} (not the empty list) is\n" | |
634 | "returned.") | |
1bbd0b84 | 635 | #define FUNC_NAME s_scm_memv |
0f2d19dd | 636 | { |
daa6ba18 | 637 | SCM_VALIDATE_LIST (2, lst); |
c96d76b8 | 638 | for (; !SCM_NULL_OR_NIL_P (lst); lst = SCM_CDR (lst)) |
daa6ba18 | 639 | { |
7888309b | 640 | if (! scm_is_false (scm_eqv_p (SCM_CAR (lst), x))) |
daa6ba18 DH |
641 | return lst; |
642 | } | |
643 | return SCM_BOOL_F; | |
0f2d19dd | 644 | } |
1bbd0b84 | 645 | #undef FUNC_NAME |
0f2d19dd JB |
646 | |
647 | ||
3b3b36dd | 648 | SCM_DEFINE (scm_member, "member", 2, 0, 0, |
1bbd0b84 | 649 | (SCM x, SCM lst), |
5352393c MG |
650 | "Return the first sublist of @var{lst} whose car is\n" |
651 | "@code{equal?} to @var{x} where the sublists of @var{lst} are\n" | |
652 | "the non-empty lists returned by @code{(list-tail @var{lst}\n" | |
653 | "@var{k})} for @var{k} less than the length of @var{lst}. If\n" | |
654 | "@var{x} does not occur in @var{lst}, then @code{#f} (not the\n" | |
655 | "empty list) is returned.") | |
1bbd0b84 | 656 | #define FUNC_NAME s_scm_member |
0f2d19dd | 657 | { |
daa6ba18 | 658 | SCM_VALIDATE_LIST (2, lst); |
c96d76b8 | 659 | for (; !SCM_NULL_OR_NIL_P (lst); lst = SCM_CDR (lst)) |
daa6ba18 | 660 | { |
7888309b | 661 | if (! scm_is_false (scm_equal_p (SCM_CAR (lst), x))) |
daa6ba18 DH |
662 | return lst; |
663 | } | |
664 | return SCM_BOOL_F; | |
0f2d19dd | 665 | } |
1bbd0b84 | 666 | #undef FUNC_NAME |
0f2d19dd | 667 | |
0f2d19dd | 668 | \f |
df13742c | 669 | /* deleting elements from a list (delq, etc.) */ |
0f2d19dd | 670 | |
3b3b36dd | 671 | SCM_DEFINE (scm_delq_x, "delq!", 2, 0, 0, |
1bbd0b84 | 672 | (SCM item, SCM lst), |
8f85c0c6 NJ |
673 | "@deffnx {Scheme Procedure} delv! item lst\n" |
674 | "@deffnx {Scheme Procedure} delete! item lst\n" | |
b380b885 | 675 | "These procedures are destructive versions of @code{delq}, @code{delv}\n" |
bfefbf18 | 676 | "and @code{delete}: they modify the existing @var{lst}\n" |
b380b885 MD |
677 | "rather than creating a new list. Caveat evaluator: Like other\n" |
678 | "destructive list functions, these functions cannot modify the binding of\n" | |
679 | "@var{lst}, and so cannot be used to delete the first element of\n" | |
680 | "@var{lst} destructively.") | |
1bbd0b84 | 681 | #define FUNC_NAME s_scm_delq_x |
0f2d19dd | 682 | { |
164271a1 JB |
683 | SCM walk; |
684 | SCM *prev; | |
0f2d19dd | 685 | |
164271a1 | 686 | for (prev = &lst, walk = lst; |
d2e53ed6 | 687 | scm_is_pair (walk); |
164271a1 | 688 | walk = SCM_CDR (walk)) |
0f2d19dd | 689 | { |
bc36d050 | 690 | if (scm_is_eq (SCM_CAR (walk), item)) |
164271a1 JB |
691 | *prev = SCM_CDR (walk); |
692 | else | |
693 | prev = SCM_CDRLOC (walk); | |
0f2d19dd | 694 | } |
164271a1 JB |
695 | |
696 | return lst; | |
0f2d19dd | 697 | } |
1bbd0b84 | 698 | #undef FUNC_NAME |
0f2d19dd JB |
699 | |
700 | ||
3b3b36dd | 701 | SCM_DEFINE (scm_delv_x, "delv!", 2, 0, 0, |
5352393c MG |
702 | (SCM item, SCM lst), |
703 | "Destructively remove all elements from @var{lst} that are\n" | |
704 | "@code{eqv?} to @var{item}.") | |
1bbd0b84 | 705 | #define FUNC_NAME s_scm_delv_x |
0f2d19dd | 706 | { |
164271a1 JB |
707 | SCM walk; |
708 | SCM *prev; | |
0f2d19dd | 709 | |
164271a1 | 710 | for (prev = &lst, walk = lst; |
d2e53ed6 | 711 | scm_is_pair (walk); |
164271a1 | 712 | walk = SCM_CDR (walk)) |
0f2d19dd | 713 | { |
7888309b | 714 | if (! scm_is_false (scm_eqv_p (SCM_CAR (walk), item))) |
164271a1 JB |
715 | *prev = SCM_CDR (walk); |
716 | else | |
717 | prev = SCM_CDRLOC (walk); | |
0f2d19dd | 718 | } |
164271a1 JB |
719 | |
720 | return lst; | |
0f2d19dd | 721 | } |
1bbd0b84 | 722 | #undef FUNC_NAME |
0f2d19dd JB |
723 | |
724 | ||
725 | ||
3b3b36dd | 726 | SCM_DEFINE (scm_delete_x, "delete!", 2, 0, 0, |
5352393c MG |
727 | (SCM item, SCM lst), |
728 | "Destructively remove all elements from @var{lst} that are\n" | |
729 | "@code{equal?} to @var{item}.") | |
1bbd0b84 | 730 | #define FUNC_NAME s_scm_delete_x |
0f2d19dd | 731 | { |
164271a1 JB |
732 | SCM walk; |
733 | SCM *prev; | |
0f2d19dd | 734 | |
164271a1 | 735 | for (prev = &lst, walk = lst; |
d2e53ed6 | 736 | scm_is_pair (walk); |
164271a1 | 737 | walk = SCM_CDR (walk)) |
0f2d19dd | 738 | { |
7888309b | 739 | if (! scm_is_false (scm_equal_p (SCM_CAR (walk), item))) |
164271a1 JB |
740 | *prev = SCM_CDR (walk); |
741 | else | |
742 | prev = SCM_CDRLOC (walk); | |
0f2d19dd | 743 | } |
164271a1 JB |
744 | |
745 | return lst; | |
0f2d19dd | 746 | } |
1bbd0b84 | 747 | #undef FUNC_NAME |
0f2d19dd JB |
748 | |
749 | ||
750 | \f | |
751 | ||
0f2d19dd | 752 | |
a1ec6916 | 753 | SCM_DEFINE (scm_delq, "delq", 2, 0, 0, |
1bbd0b84 | 754 | (SCM item, SCM lst), |
5352393c MG |
755 | "Return a newly-created copy of @var{lst} with elements\n" |
756 | "@code{eq?} to @var{item} removed. This procedure mirrors\n" | |
757 | "@code{memq}: @code{delq} compares elements of @var{lst} against\n" | |
758 | "@var{item} with @code{eq?}.") | |
1bbd0b84 | 759 | #define FUNC_NAME s_scm_delq |
0f2d19dd | 760 | { |
1bbd0b84 | 761 | SCM copy = scm_list_copy (lst); |
0f2d19dd JB |
762 | return scm_delq_x (item, copy); |
763 | } | |
1bbd0b84 | 764 | #undef FUNC_NAME |
0f2d19dd | 765 | |
a1ec6916 | 766 | SCM_DEFINE (scm_delv, "delv", 2, 0, 0, |
1bbd0b84 | 767 | (SCM item, SCM lst), |
5352393c MG |
768 | "Return a newly-created copy of @var{lst} with elements\n" |
769 | "@code{eqv?} to @var{item} removed. This procedure mirrors\n" | |
770 | "@code{memv}: @code{delv} compares elements of @var{lst} against\n" | |
771 | "@var{item} with @code{eqv?}.") | |
1bbd0b84 | 772 | #define FUNC_NAME s_scm_delv |
0f2d19dd | 773 | { |
1bbd0b84 | 774 | SCM copy = scm_list_copy (lst); |
0f2d19dd JB |
775 | return scm_delv_x (item, copy); |
776 | } | |
1bbd0b84 | 777 | #undef FUNC_NAME |
0f2d19dd | 778 | |
a1ec6916 | 779 | SCM_DEFINE (scm_delete, "delete", 2, 0, 0, |
1bbd0b84 | 780 | (SCM item, SCM lst), |
5352393c MG |
781 | "Return a newly-created copy of @var{lst} with elements\n" |
782 | "@code{equal?} to @var{item} removed. This procedure mirrors\n" | |
783 | "@code{member}: @code{delete} compares elements of @var{lst}\n" | |
784 | "against @var{item} with @code{equal?}.") | |
1bbd0b84 | 785 | #define FUNC_NAME s_scm_delete |
0f2d19dd | 786 | { |
1bbd0b84 | 787 | SCM copy = scm_list_copy (lst); |
0f2d19dd JB |
788 | return scm_delete_x (item, copy); |
789 | } | |
1bbd0b84 | 790 | #undef FUNC_NAME |
0f2d19dd JB |
791 | |
792 | ||
3b3b36dd | 793 | SCM_DEFINE (scm_delq1_x, "delq1!", 2, 0, 0, |
1bbd0b84 | 794 | (SCM item, SCM lst), |
5352393c MG |
795 | "Like @code{delq!}, but only deletes the first occurrence of\n" |
796 | "@var{item} from @var{lst}. Tests for equality using\n" | |
797 | "@code{eq?}. See also @code{delv1!} and @code{delete1!}.") | |
1bbd0b84 | 798 | #define FUNC_NAME s_scm_delq1_x |
82dc9f57 MD |
799 | { |
800 | SCM walk; | |
801 | SCM *prev; | |
802 | ||
803 | for (prev = &lst, walk = lst; | |
d2e53ed6 | 804 | scm_is_pair (walk); |
82dc9f57 MD |
805 | walk = SCM_CDR (walk)) |
806 | { | |
bc36d050 | 807 | if (scm_is_eq (SCM_CAR (walk), item)) |
82dc9f57 MD |
808 | { |
809 | *prev = SCM_CDR (walk); | |
810 | break; | |
811 | } | |
812 | else | |
813 | prev = SCM_CDRLOC (walk); | |
814 | } | |
815 | ||
816 | return lst; | |
817 | } | |
1bbd0b84 | 818 | #undef FUNC_NAME |
82dc9f57 MD |
819 | |
820 | ||
3b3b36dd | 821 | SCM_DEFINE (scm_delv1_x, "delv1!", 2, 0, 0, |
8507b88c | 822 | (SCM item, SCM lst), |
5352393c MG |
823 | "Like @code{delv!}, but only deletes the first occurrence of\n" |
824 | "@var{item} from @var{lst}. Tests for equality using\n" | |
825 | "@code{eqv?}. See also @code{delq1!} and @code{delete1!}.") | |
1bbd0b84 | 826 | #define FUNC_NAME s_scm_delv1_x |
82dc9f57 MD |
827 | { |
828 | SCM walk; | |
829 | SCM *prev; | |
830 | ||
831 | for (prev = &lst, walk = lst; | |
d2e53ed6 | 832 | scm_is_pair (walk); |
82dc9f57 MD |
833 | walk = SCM_CDR (walk)) |
834 | { | |
7888309b | 835 | if (! scm_is_false (scm_eqv_p (SCM_CAR (walk), item))) |
82dc9f57 MD |
836 | { |
837 | *prev = SCM_CDR (walk); | |
838 | break; | |
839 | } | |
840 | else | |
841 | prev = SCM_CDRLOC (walk); | |
842 | } | |
843 | ||
844 | return lst; | |
845 | } | |
1bbd0b84 | 846 | #undef FUNC_NAME |
82dc9f57 MD |
847 | |
848 | ||
3b3b36dd | 849 | SCM_DEFINE (scm_delete1_x, "delete1!", 2, 0, 0, |
8507b88c | 850 | (SCM item, SCM lst), |
5352393c MG |
851 | "Like @code{delete!}, but only deletes the first occurrence of\n" |
852 | "@var{item} from @var{lst}. Tests for equality using\n" | |
853 | "@code{equal?}. See also @code{delq1!} and @code{delv1!}.") | |
1bbd0b84 | 854 | #define FUNC_NAME s_scm_delete1_x |
82dc9f57 MD |
855 | { |
856 | SCM walk; | |
857 | SCM *prev; | |
858 | ||
859 | for (prev = &lst, walk = lst; | |
d2e53ed6 | 860 | scm_is_pair (walk); |
82dc9f57 MD |
861 | walk = SCM_CDR (walk)) |
862 | { | |
7888309b | 863 | if (! scm_is_false (scm_equal_p (SCM_CAR (walk), item))) |
82dc9f57 MD |
864 | { |
865 | *prev = SCM_CDR (walk); | |
866 | break; | |
867 | } | |
868 | else | |
869 | prev = SCM_CDRLOC (walk); | |
870 | } | |
871 | ||
872 | return lst; | |
873 | } | |
1bbd0b84 | 874 | #undef FUNC_NAME |
82dc9f57 | 875 | |
c614a00b MD |
876 | SCM_DEFINE (scm_filter, "filter", 2, 0, 0, |
877 | (SCM pred, SCM list), | |
878 | "Return all the elements of 2nd arg @var{list} that satisfy predicate @var{pred}.\n" | |
879 | "The list is not disordered -- elements that appear in the result list occur\n" | |
880 | "in the same order as they occur in the argument list. The returned list may\n" | |
881 | "share a common tail with the argument list. The dynamic order in which the\n" | |
882 | "various applications of pred are made is not specified.\n\n" | |
883 | "@lisp\n" | |
884 | "(filter even? '(0 7 8 8 43 -4)) => (0 8 8 -4)\n" | |
885 | "@end lisp") | |
886 | #define FUNC_NAME s_scm_filter | |
887 | { | |
c614a00b MD |
888 | SCM walk; |
889 | SCM *prev; | |
890 | SCM res = SCM_EOL; | |
6c9e8a53 | 891 | SCM_ASSERT (scm_is_true (scm_procedure_p (pred)), pred, 1, FUNC_NAME); |
c614a00b MD |
892 | SCM_VALIDATE_LIST (2, list); |
893 | ||
894 | for (prev = &res, walk = list; | |
d2e53ed6 | 895 | scm_is_pair (walk); |
c614a00b MD |
896 | walk = SCM_CDR (walk)) |
897 | { | |
6c9e8a53 | 898 | if (scm_is_true (scm_call_1 (pred, SCM_CAR (walk)))) |
c614a00b MD |
899 | { |
900 | *prev = scm_cons (SCM_CAR (walk), SCM_EOL); | |
901 | prev = SCM_CDRLOC (*prev); | |
902 | } | |
903 | } | |
904 | ||
905 | return res; | |
906 | } | |
907 | #undef FUNC_NAME | |
908 | ||
909 | SCM_DEFINE (scm_filter_x, "filter!", 2, 0, 0, | |
910 | (SCM pred, SCM list), | |
911 | "Linear-update variant of @code{filter}.") | |
912 | #define FUNC_NAME s_scm_filter_x | |
913 | { | |
c614a00b MD |
914 | SCM walk; |
915 | SCM *prev; | |
6c9e8a53 | 916 | SCM_ASSERT (scm_is_true (scm_procedure_p (pred)), pred, 1, FUNC_NAME); |
c614a00b MD |
917 | SCM_VALIDATE_LIST (2, list); |
918 | ||
919 | for (prev = &list, walk = list; | |
d2e53ed6 | 920 | scm_is_pair (walk); |
c614a00b MD |
921 | walk = SCM_CDR (walk)) |
922 | { | |
6c9e8a53 | 923 | if (scm_is_true (scm_call_1 (pred, SCM_CAR (walk)))) |
c614a00b MD |
924 | prev = SCM_CDRLOC (walk); |
925 | else | |
926 | *prev = SCM_CDR (walk); | |
927 | } | |
928 | ||
929 | return list; | |
930 | } | |
931 | #undef FUNC_NAME | |
82dc9f57 | 932 | |
0f2d19dd | 933 | \f |
0f2d19dd JB |
934 | void |
935 | scm_init_list () | |
0f2d19dd | 936 | { |
a0599745 | 937 | #include "libguile/list.x" |
0f2d19dd | 938 | } |
89e00824 ML |
939 | |
940 | /* | |
941 | Local Variables: | |
942 | c-file-style: "gnu" | |
943 | End: | |
944 | */ |