libguile/alist.c

   1 /*      Copyright (C) 1995, 1996, 1998 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 "_scm.h"
  48 #include "eq.h"
  49 #include "list.h"
  50
  51 #include "scm_validate.h"
  52 #include "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
  59 created whose car is @var{key} and whose cdr is @var{value}, and the
  60 pair is consed onto @var{alist}, and the new list is returned.  This
  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.
  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_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.
 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.
 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
 140 @deffnx primitive assoc key alist
 141 Fetches the entry in @var{alist} that is associated with @var{key}.  To
 142 decide whether the argument @var{key} matches a particular entry in
 143 @var{alist}, @code{assq} compares keys with @code{eq?}, @code{assv}
 144 uses @code{eqv?} and @code{assoc} uses @code{equal?}.  If @var{key}
 145 cannot be found in @var{alist} (according to whichever equality
 146 predicate is in use), then @code{#f} is returned.  These functions
 147 return the entire alist entry found (i.e. both the key and the value).")
 148 #define FUNC_NAME s_scm_assq
 149 {
 150   SCM tmp;
 151   for(;SCM_NIMP(alist);alist = SCM_CDR(alist)) {
 152     SCM_VALIDATE_ALISTCELL_COPYSCM(2,alist,tmp);
 153     if (SCM_CAR(tmp)==key) return tmp;
 154   }
 155   SCM_VALIDATE_NULL(2,alist);
 156   return SCM_BOOL_F;
 157 }
 158 #undef FUNC_NAME
 159
 160
 161 SCM_DEFINE(scm_assv, "assv", 2, 0, 0,
 162            (SCM key, SCM alist),
 163 "Behaves like @code{assq} but uses @code{eqv?} for key comparison.")
 164 #define FUNC_NAME s_scm_assv
 165 {
 166   SCM tmp;
 167   for(;SCM_NIMP(alist);alist = SCM_CDR(alist)) {
 168     SCM_ASRTGO(SCM_CONSP(alist), badlst);
 169     tmp = SCM_CAR(alist);
 170     SCM_ASRTGO(SCM_CONSP(tmp), badlst);
 171     if SCM_NFALSEP(scm_eqv_p(SCM_CAR(tmp), key)) return tmp;
 172   }
 173 # ifndef SCM_RECKLESS
 174   if (!(SCM_NULLP(alist)))
 175     badlst: SCM_WTA(2,alist);
 176 # endif
 177   return SCM_BOOL_F;
 178 }
 179 #undef FUNC_NAME
 180
 181
 182 SCM_DEFINE(scm_assoc, "assoc", 2, 0, 0,
 183            (SCM key, SCM alist),
 184 "Behaves like @code{assq} but uses @code{equal?} for key comparison.")
 185 #define FUNC_NAME s_scm_assoc
 186 {
 187   SCM tmp;
 188   for(;SCM_NIMP(alist);alist = SCM_CDR(alist)) {
 189     SCM_VALIDATE_ALISTCELL_COPYSCM(2,alist,tmp);
 190     if SCM_NFALSEP(scm_equal_p(SCM_CAR(tmp), key)) return tmp;
 191   }
 192   SCM_VALIDATE_NULL(2,alist);
 193   return SCM_BOOL_F;
 194 }
 195 #undef FUNC_NAME
 196
 197
 198 \f
 199
 200 SCM_DEFINE (scm_assq_ref, "assq-ref", 2, 0, 0,
 201             (SCM alist, SCM key),
 202 "@deffnx primitive assv-ref alist key
 203 @deffnx primitive assoc-ref alist key
 204 Like @code{assq}, @code{assv} and @code{assoc}, except that only the
 205 value associated with @var{key} in @var{alist} is returned.  These
 206 functions are equivalent to
 207
 208 @lisp
 209 (let ((ent (@var{associator} @var{key} @var{alist})))
 210   (and ent (cdr ent)))
 211 @end lisp
 212
 213 where @var{associator} is one of @code{assq}, @code{assv} or @code{assoc}.")
 214 #define FUNC_NAME s_scm_assq_ref
 215 {
 216   SCM handle;
 217
 218   handle = scm_sloppy_assq (key, alist);
 219   if (SCM_CONSP (handle))
 220     {
 221       return SCM_CDR (handle);
 222     }
 223   return SCM_BOOL_F;
 224 }
 225 #undef FUNC_NAME
 226
 227
 228 SCM_DEFINE (scm_assv_ref, "assv-ref", 2, 0, 0,
 229             (SCM alist, SCM key),
 230 "Behaves like @code{assq-ref} but uses @code{eqv?} for key comparison.")
 231 #define FUNC_NAME s_scm_assv_ref
 232 {
 233   SCM handle;
 234
 235   handle = scm_sloppy_assv (key, alist);
 236   if (SCM_CONSP (handle))
 237     {
 238       return SCM_CDR (handle);
 239     }
 240   return SCM_BOOL_F;
 241 }
 242 #undef FUNC_NAME
 243
 244
 245 SCM_DEFINE (scm_assoc_ref, "assoc-ref", 2, 0, 0,
 246             (SCM alist, SCM key),
 247 "Behaves like @code{assq-ref} but uses @code{equal?} for key comparison.")
 248 #define FUNC_NAME s_scm_assoc_ref
 249 {
 250   SCM handle;
 251
 252   handle = scm_sloppy_assoc (key, alist);
 253   if (SCM_CONSP (handle))
 254     {
 255       return SCM_CDR (handle);
 256     }
 257   return SCM_BOOL_F;
 258 }
 259 #undef FUNC_NAME
 260
 261
 262
 263 \f
 264
 265
 266 SCM_DEFINE (scm_assq_set_x, "assq-set!", 3, 0, 0,
 267             (SCM alist, SCM key, SCM val),
 268 "@deffnx primitive assv-set! alist key value
 269 @deffnx primitive assoc-set! alist key value
 270 Reassociate @var{key} in @var{alist} with @var{value}: find any existing
 271 @var{alist} entry for @var{key} and associate it with the new
 272 @var{value}.  If @var{alist} does not contain an entry for @var{key},
 273 add a new one.  Return the (possibly new) alist.
 274
 275 These functions do not attempt to verify the structure of @var{alist},
 276 and so may cause unusual results if passed an object that is not an
 277 association list.")
 278 #define FUNC_NAME s_scm_assq_set_x
 279 {
 280   SCM handle;
 281
 282   handle = scm_sloppy_assq (key, alist);
 283   if (SCM_CONSP (handle))
 284     {
 285       SCM_SETCDR (handle, val);
 286       return alist;
 287     }
 288   else
 289     return scm_acons (key, val, alist);
 290 }
 291 #undef FUNC_NAME
 292
 293 SCM_DEFINE (scm_assv_set_x, "assv-set!", 3, 0, 0,
 294             (SCM alist, SCM key, SCM val),
 295 "Behaves like @code{assq-set!} but uses @code{eqv?} for key comparison.")
 296 #define FUNC_NAME s_scm_assv_set_x
 297 {
 298   SCM handle;
 299
 300   handle = scm_sloppy_assv (key, alist);
 301   if (SCM_CONSP (handle))
 302     {
 303       SCM_SETCDR (handle, val);
 304       return alist;
 305     }
 306   else
 307     return scm_acons (key, val, alist);
 308 }
 309 #undef FUNC_NAME
 310
 311 SCM_DEFINE (scm_assoc_set_x, "assoc-set!", 3, 0, 0,
 312             (SCM alist, SCM key, SCM val),
 313 "Behaves like @code{assq-set!} but uses @code{equal?} for key comparison.")
 314 #define FUNC_NAME s_scm_assoc_set_x
 315 {
 316   SCM handle;
 317
 318   handle = scm_sloppy_assoc (key, alist);
 319   if (SCM_CONSP (handle))
 320     {
 321       SCM_SETCDR (handle, val);
 322       return alist;
 323     }
 324   else
 325     return scm_acons (key, val, alist);
 326 }
 327 #undef FUNC_NAME
 328
 329
 330 \f
 331
 332 SCM_DEFINE (scm_assq_remove_x, "assq-remove!", 2, 0, 0,
 333             (SCM alist, SCM key),
 334 "@deffnx primitive assv-remove! alist key
 335 @deffnx primitive assoc-remove! alist key
 336 Delete any entry in @var{alist} associated with @var{key}, and return
 337 the resulting alist.")
 338 #define FUNC_NAME s_scm_assq_remove_x
 339 {
 340   SCM handle;
 341
 342   handle = scm_sloppy_assq (key, alist);
 343   if (SCM_CONSP (handle))
 344     {
 345       return scm_delq_x (handle, alist);
 346     }
 347   else
 348     return alist;
 349 }
 350 #undef FUNC_NAME
 351
 352
 353 SCM_DEFINE (scm_assv_remove_x, "assv-remove!", 2, 0, 0,
 354             (SCM alist, SCM key),
 355 "Behaves like @code{assq-remove!} but uses @code{eqv?} for key comparison.")
 356 #define FUNC_NAME s_scm_assv_remove_x
 357 {
 358   SCM handle;
 359
 360   handle = scm_sloppy_assv (key, alist);
 361   if (SCM_CONSP (handle))
 362     {
 363       return scm_delv_x (handle, alist);
 364     }
 365   else
 366     return alist;
 367 }
 368 #undef FUNC_NAME
 369
 370
 371 SCM_DEFINE (scm_assoc_remove_x, "assoc-remove!", 2, 0, 0,
 372             (SCM alist, SCM key),
 373 "Behaves like @code{assq-remove!} but uses @code{equal?} for key comparison.")
 374 #define FUNC_NAME s_scm_assoc_remove_x
 375 {
 376   SCM handle;
 377
 378   handle = scm_sloppy_assoc (key, alist);
 379   if (SCM_CONSP (handle))
 380     {
 381       return scm_delete_x (handle, alist);
 382     }
 383   else
 384     return alist;
 385 }
 386 #undef FUNC_NAME
 387
 388
 389 \f
 390
 391
 392
 393 void
 394 scm_init_alist ()
 395 {
 396 #include "alist.x"
 397 }
 398