libguile/objprop.c

   1 /*      Copyright (C) 1995,1996, 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
  47 #include "libguile/_scm.h"
  48 #include "libguile/hashtab.h"
  49 #include "libguile/alist.h"
  50 #include "libguile/root.h"
  51 #include "libguile/weaks.h"
  52
  53 #include "libguile/objprop.h"
  54 \f
  55
  56 /* {Object Properties}
  57  */
  58
  59 SCM_DEFINE (scm_object_properties, "object-properties", 1, 0, 0,
  60            (SCM obj),
  61             "@deffnx primitive procedure-properties obj\n"
  62             "Return @var{obj}'s property list.")
  63 #define FUNC_NAME s_scm_object_properties
  64 {
  65   return scm_hashq_ref (scm_object_whash, obj, SCM_EOL);
  66 }
  67 #undef FUNC_NAME
  68
  69
  70 SCM_DEFINE (scm_set_object_properties_x, "set-object-properties!", 2, 0, 0,
  71            (SCM obj, SCM plist),
  72             "@deffnx primitive set-procedure-properties! obj alist\n"
  73             "Set @var{obj}'s property list to @var{alist}.")
  74 #define FUNC_NAME s_scm_set_object_properties_x
  75 {
  76   SCM handle = scm_hashq_create_handle_x (scm_object_whash, obj, plist);
  77   SCM_SETCDR (handle, plist);
  78   return plist;
  79 }
  80 #undef FUNC_NAME
  81
  82 SCM_DEFINE (scm_object_property, "object-property", 2, 0, 0,
  83            (SCM obj, SCM key),
  84             "@deffnx primitive procedure-property obj key\n"
  85             "Return the property of @var{obj} with name @var{key}.")
  86 #define FUNC_NAME s_scm_object_property
  87 {
  88   SCM assoc;
  89   assoc = scm_assq (key, scm_object_properties (obj));
  90   return (SCM_NIMP (assoc) ? SCM_CDR (assoc) : SCM_BOOL_F);
  91 }
  92 #undef FUNC_NAME
  93
  94 SCM_DEFINE (scm_set_object_property_x, "set-object-property!", 3, 0, 0,
  95            (SCM obj, SCM key, SCM val),
  96             "@deffnx primitive set-procedure-property! obj key value\n"
  97             "In @var{obj}'s property list, set the property named @var{key} to\n"
  98             "@var{value}.")
  99 #define FUNC_NAME s_scm_set_object_property_x
 100 {
 101   SCM h;
 102   SCM assoc;
 103   h = scm_hashq_create_handle_x (scm_object_whash, obj, SCM_EOL);
 104   SCM_DEFER_INTS;
 105   assoc = scm_assq (key, SCM_CDR (h));
 106   if (SCM_NIMP (assoc))
 107     SCM_SETCDR (assoc, val);
 108   else
 109     {
 110       assoc = scm_acons (key, val, SCM_CDR (h));
 111       SCM_SETCDR (h, assoc);
 112     }
 113   SCM_ALLOW_INTS;
 114   return val;
 115 }
 116 #undef FUNC_NAME
 117
 118
 119 void
 120 scm_init_objprop ()
 121 {
 122   scm_object_whash = scm_make_weak_key_hash_table (SCM_MAKINUM (511));
 123 #ifndef SCM_MAGIC_SNARFER
 124 #include "libguile/objprop.x"
 125 #endif
 126 }
 127
 128
 129 /*
 130   Local Variables:
 131   c-file-style: "gnu"
 132   End:
 133 */