libguile/alist.c

   1 /* Copyright (C) 1995, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  16  * Boston, MA 02111-1307 USA
  17  *
  18  * As a special exception, the Free Software Foundation gives permission
  19  * for additional uses of the text contained in its release of GUILE.
  20  *
  21  * The exception is that, if you link the GUILE library with other files
  22  * to produce an executable, this does not by itself cause the
  23  * resulting executable to be covered by the GNU General Public License.
  24  * Your use of that executable is in no way restricted on account of
  25  * linking the GUILE library code into it.
  26  *
  27  * This exception does not however invalidate any other reasons why
  28  * the executable file might be covered by the GNU General Public License.
  29  *
  30  * This exception applies only to the code released by the
  31  * Free Software Foundation under the name GUILE.  If you copy
  32  * code from other Free Software Foundation releases into a copy of
  33  * GUILE, as the General Public License permits, the exception does
  34  * not apply to the code that you add in this way.  To avoid misleading
  35  * anyone as to the status of such modified files, you must delete
  36  * this exception notice from them.
  37  *
  38  * If you write modifications of your own for GUILE, it is your choice
  39  * whether to permit this exception to apply to your modifications.
  40  * If you do not wish that, delete this exception notice.  */
  41
  42 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  43    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  44
  45 \f
  46 #include <stdio.h>
  47 #include "libguile/_scm.h"
  48 #include "libguile/eq.h"
  49 #include "libguile/list.h"
  50
  51 #include "libguile/validate.h"
  52 #include "libguile/alist.h"
  53
  54 \f
  55
  56 SCM_DEFINE (scm_acons, "acons", 3, 0, 0,
  57            (SCM key, SCM value, SCM alist),
  58             "Adds a new key-value pair to @var{alist}.  A new pair is\n"
  59             "created whose car is @var{key} and whose cdr is @var{value}, and the\n"
  60             "pair is consed onto @var{alist}, and the new list is returned.  This\n"
  61             "function is @emph{not} destructive; @var{alist} is not modified.")
  62 #define FUNC_NAME s_scm_acons
  63 {
  64   SCM pair;
  65   SCM head;
  66
  67   SCM_NEWCELL (pair);
  68   SCM_SETCAR (pair, key);
  69   SCM_SETCDR (pair, value);
  70
  71   SCM_NEWCELL (head);
  72   SCM_SETCAR (head, pair);
  73   SCM_SETCDR (head, alist);
  74
  75   return head;
  76 }
  77 #undef FUNC_NAME
  78
  79 \f
  80
  81 SCM_DEFINE (scm_sloppy_assq, "sloppy-assq", 2, 0, 0,
  82             (SCM key, SCM alist),
  83             "Behaves like @code{assq} but does not do any error checking.\n"
  84             "Recommended only for use in Guile internals.")
  85 #define FUNC_NAME s_scm_sloppy_assq
  86 {
  87   for (; SCM_CONSP (alist); alist = SCM_CDR (alist))
  88     {
  89       SCM tmp = SCM_CAR (alist);
  90       if (SCM_CONSP (tmp) && SCM_EQ_P (SCM_CAR (tmp), key))
  91         return tmp;
  92     }
  93   return SCM_BOOL_F;
  94 }
  95 #undef FUNC_NAME
  96
  97
  98
  99 SCM_DEFINE (scm_sloppy_assv, "sloppy-assv", 2, 0, 0,
 100             (SCM key, SCM alist),
 101             "Behaves like @code{assv} but does not do any error checking.\n"
 102             "Recommended only for use in Guile internals.")
 103 #define FUNC_NAME s_scm_sloppy_assv
 104 {
 105   for (; SCM_CONSP (alist); alist = SCM_CDR (alist))
 106     {
 107       SCM tmp = SCM_CAR (alist);
 108       if (SCM_CONSP (tmp)
 109           && SCM_NFALSEP (scm_eqv_p (SCM_CAR (tmp), key)))
 110         return tmp;
 111     }
 112   return SCM_BOOL_F;
 113 }
 114 #undef FUNC_NAME
 115
 116
 117 SCM_DEFINE (scm_sloppy_assoc, "sloppy-assoc", 2, 0, 0,
 118             (SCM key, SCM alist),
 119             "Behaves like @code{assoc} but does not do any error checking.\n"
 120             "Recommended only for use in Guile internals.")
 121 #define FUNC_NAME s_scm_sloppy_assoc
 122 {
 123   for (; SCM_CONSP (alist); alist = SCM_CDR (alist))
 124     {
 125       SCM tmp = SCM_CAR (alist);
 126       if (SCM_CONSP (tmp)
 127           && SCM_NFALSEP (scm_equal_p (SCM_CAR (tmp), key)))
 128         return tmp;
 129     }
 130   return SCM_BOOL_F;
 131 }
 132 #undef FUNC_NAME
 133
 134
 135 \f
 136
 137 SCM_DEFINE (scm_assq, "assq", 2, 0, 0,
 138            (SCM key, SCM alist),
 139             "@deffnx primitive assv key alist\n"
 140             "@deffnx primitive assoc key alist\n"
 141             "Fetches the entry in @var{alist} that is associated with @var{key}.  To\n"
 142             "decide whether the argument @var{key} matches a particular entry in\n"
 143             "@var{alist}, @code{assq} compares keys with @code{eq?}, @code{assv}\n"
 144             "uses @code{eqv?} and @code{assoc} uses @code{equal?}.  If @var{key}\n"
 145             "cannot be found in @var{alist} (according to whichever equality\n"
 146             "predicate is in use), then @code{#f} is returned.  These functions\n"
 147             "return the entire alist entry found (i.e. both the key and the value).")
 148 #define FUNC_NAME s_scm_assq
 149 {
 150   for (; SCM_CONSP (alist); alist = SCM_CDR (alist))
 151     {
 152       SCM tmp = SCM_CAR (alist);
 153       SCM_VALIDATE_CONS (SCM_ARG2, tmp);
 154       if (SCM_EQ_P (SCM_CAR (tmp), key))
 155         return tmp;
 156     }
 157   SCM_VALIDATE_NULL (2, alist);
 158   return SCM_BOOL_F;
 159 }
 160 #undef FUNC_NAME
 161
 162
 163 SCM_DEFINE (scm_assv, "assv", 2, 0, 0,
 164            (SCM key, SCM alist),
 165             "Behaves like @code{assq} but uses @code{eqv?} for key comparison.")
 166 #define FUNC_NAME s_scm_assv
 167 {
 168   for(; SCM_CONSP (alist); alist = SCM_CDR (alist))
 169     {
 170       SCM tmp = SCM_CAR (alist);
 171       SCM_VALIDATE_CONS (SCM_ARG2, tmp);
 172       if (SCM_NFALSEP (scm_eqv_p (SCM_CAR (tmp), key)))
 173         return tmp;
 174     }
 175   SCM_VALIDATE_NULL (2, alist);
 176   return SCM_BOOL_F;
 177 }
 178 #undef FUNC_NAME
 179
 180
 181 SCM_DEFINE (scm_assoc, "assoc", 2, 0, 0,
 182            (SCM key, SCM alist),
 183             "Behaves like @code{assq} but uses @code{equal?} for key comparison.")
 184 #define FUNC_NAME s_scm_assoc
 185 {
 186   for(; SCM_CONSP (alist); alist = SCM_CDR (alist))
 187     {
 188       SCM tmp = SCM_CAR (alist);
 189       SCM_VALIDATE_CONS (SCM_ARG2, tmp);
 190       if (SCM_NFALSEP (scm_equal_p (SCM_CAR (tmp), key)))
 191         return tmp;
 192     }
 193   SCM_VALIDATE_NULL (2, alist);
 194   return SCM_BOOL_F;
 195 }
 196 #undef FUNC_NAME
 197
 198
 199 \f
 200
 201 SCM_DEFINE (scm_assq_ref, "assq-ref", 2, 0, 0,
 202             (SCM alist, SCM key),
 203             "@deffnx primitive assv-ref alist key\n"
 204             "@deffnx primitive assoc-ref alist key\n"
 205             "Like @code{assq}, @code{assv} and @code{assoc}, except that only the\n"
 206             "value associated with @var{key} in @var{alist} is returned.  These\n"
 207             "functions are equivalent to\n\n"
 208             "@lisp\n"
 209             "(let ((ent (@var{associator} @var{key} @var{alist})))\n"
 210             "  (and ent (cdr ent)))\n"
 211             "@end lisp\n\n"
 212             "where @var{associator} is one of @code{assq}, @code{assv} or @code{assoc}.")
 213 #define FUNC_NAME s_scm_assq_ref
 214 {
 215   SCM handle;
 216
 217   handle = scm_sloppy_assq (key, alist);
 218   if (SCM_CONSP (handle))
 219     {
 220       return SCM_CDR (handle);
 221     }
 222   return SCM_BOOL_F;
 223 }
 224 #undef FUNC_NAME
 225
 226
 227 SCM_DEFINE (scm_assv_ref, "assv-ref", 2, 0, 0,
 228             (SCM alist, SCM key),
 229             "Behaves like @code{assq-ref} but uses @code{eqv?} for key comparison.")
 230 #define FUNC_NAME s_scm_assv_ref
 231 {
 232   SCM handle;
 233
 234   handle = scm_sloppy_assv (key, alist);
 235   if (SCM_CONSP (handle))
 236     {
 237       return SCM_CDR (handle);
 238     }
 239   return SCM_BOOL_F;
 240 }
 241 #undef FUNC_NAME
 242
 243
 244 SCM_DEFINE (scm_assoc_ref, "assoc-ref", 2, 0, 0,
 245             (SCM alist, SCM key),
 246             "Behaves like @code{assq-ref} but uses @code{equal?} for key comparison.")
 247 #define FUNC_NAME s_scm_assoc_ref
 248 {
 249   SCM handle;
 250
 251   handle = scm_sloppy_assoc (key, alist);
 252   if (SCM_CONSP (handle))
 253     {
 254       return SCM_CDR (handle);
 255     }
 256   return SCM_BOOL_F;
 257 }
 258 #undef FUNC_NAME
 259
 260
 261
 262 \f
 263
 264
 265 SCM_DEFINE (scm_assq_set_x, "assq-set!", 3, 0, 0,
 266             (SCM alist, SCM key, SCM val),
 267             "@deffnx primitive assv-set! alist key value\n"
 268             "@deffnx primitive assoc-set! alist key value\n"
 269             "Reassociate @var{key} in @var{alist} with @var{value}: find any existing\n"
 270             "@var{alist} entry for @var{key} and associate it with the new\n"
 271             "@var{value}.  If @var{alist} does not contain an entry for @var{key},\n"
 272             "add a new one.  Return the (possibly new) alist.\n\n"
 273             "These functions do not attempt to verify the structure of @var{alist},\n"
 274             "and so may cause unusual results if passed an object that is not an\n"
 275             "association list.")
 276 #define FUNC_NAME s_scm_assq_set_x
 277 {
 278   SCM handle;
 279
 280   handle = scm_sloppy_assq (key, alist);
 281   if (SCM_CONSP (handle))
 282     {
 283       SCM_SETCDR (handle, val);
 284       return alist;
 285     }
 286   else
 287     return scm_acons (key, val, alist);
 288 }
 289 #undef FUNC_NAME
 290
 291 SCM_DEFINE (scm_assv_set_x, "assv-set!", 3, 0, 0,
 292             (SCM alist, SCM key, SCM val),
 293             "Behaves like @code{assq-set!} but uses @code{eqv?} for key comparison.")
 294 #define FUNC_NAME s_scm_assv_set_x
 295 {
 296   SCM handle;
 297
 298   handle = scm_sloppy_assv (key, alist);
 299   if (SCM_CONSP (handle))
 300     {
 301       SCM_SETCDR (handle, val);
 302       return alist;
 303     }
 304   else
 305     return scm_acons (key, val, alist);
 306 }
 307 #undef FUNC_NAME
 308
 309 SCM_DEFINE (scm_assoc_set_x, "assoc-set!", 3, 0, 0,
 310             (SCM alist, SCM key, SCM val),
 311             "Behaves like @code{assq-set!} but uses @code{equal?} for key comparison.")
 312 #define FUNC_NAME s_scm_assoc_set_x
 313 {
 314   SCM handle;
 315
 316   handle = scm_sloppy_assoc (key, alist);
 317   if (SCM_CONSP (handle))
 318     {
 319       SCM_SETCDR (handle, val);
 320       return alist;
 321     }
 322   else
 323     return scm_acons (key, val, alist);
 324 }
 325 #undef FUNC_NAME
 326
 327
 328 \f
 329
 330 SCM_DEFINE (scm_assq_remove_x, "assq-remove!", 2, 0, 0,
 331             (SCM alist, SCM key),
 332             "@deffnx primitive assv-remove! alist key\n"
 333             "@deffnx primitive assoc-remove! alist key\n"
 334             "Delete any entry in @var{alist} associated with @var{key}, and return\n"
 335             "the resulting alist.")
 336 #define FUNC_NAME s_scm_assq_remove_x
 337 {
 338   SCM handle;
 339
 340   handle = scm_sloppy_assq (key, alist);
 341   if (SCM_CONSP (handle))
 342     {
 343       return scm_delq_x (handle, alist);
 344     }
 345   else
 346     return alist;
 347 }
 348 #undef FUNC_NAME
 349
 350
 351 SCM_DEFINE (scm_assv_remove_x, "assv-remove!", 2, 0, 0,
 352             (SCM alist, SCM key),
 353             "Behaves like @code{assq-remove!} but uses @code{eqv?} for key comparison.")
 354 #define FUNC_NAME s_scm_assv_remove_x
 355 {
 356   SCM handle;
 357
 358   handle = scm_sloppy_assv (key, alist);
 359   if (SCM_CONSP (handle))
 360     {
 361       return scm_delv_x (handle, alist);
 362     }
 363   else
 364     return alist;
 365 }
 366 #undef FUNC_NAME
 367
 368
 369 SCM_DEFINE (scm_assoc_remove_x, "assoc-remove!", 2, 0, 0,
 370             (SCM alist, SCM key),
 371             "Behaves like @code{assq-remove!} but uses @code{equal?} for key comparison.")
 372 #define FUNC_NAME s_scm_assoc_remove_x
 373 {
 374   SCM handle;
 375
 376   handle = scm_sloppy_assoc (key, alist);
 377   if (SCM_CONSP (handle))
 378     {
 379       return scm_delete_x (handle, alist);
 380     }
 381   else
 382     return alist;
 383 }
 384 #undef FUNC_NAME
 385
 386
 387 \f
 388
 389
 390
 391 void
 392 scm_init_alist ()
 393 {
 394 #include "libguile/alist.x"
 395 }
 396
 397
 398 /*
 399   Local Variables:
 400   c-file-style: "gnu"
 401   End:
 402 */