libguile/procprop.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
  47 #include <stdio.h>
  48 #include "_scm.h"
  49
  50 #include "alist.h"
  51 #include "eval.h"
  52 #include "procs.h"
  53 #include "gsubr.h"
  54 #include "objects.h"
  55 #include "root.h"
  56 #include "vectors.h"
  57
  58 #include "validate.h"
  59 #include "procprop.h"
  60 \f
  61
  62 SCM_GLOBAL_SYMBOL (scm_sym_system_procedure, "system-procedure");
  63 SCM_GLOBAL_SYMBOL (scm_sym_arity, "arity");
  64
  65 SCM
  66 scm_i_procedure_arity (SCM proc)
  67 {
  68   int a = 0, o = 0, r = 0;
  69   if (SCM_IMP (proc))
  70     return SCM_BOOL_F;
  71  loop:
  72   switch (SCM_TYP7 (proc))
  73     {
  74     case scm_tc7_subr_1o:
  75       o = 1;
  76     case scm_tc7_subr_0:
  77       break;
  78     case scm_tc7_subr_2o:
  79       o = 1;
  80     case scm_tc7_subr_1:
  81     case scm_tc7_cxr:
  82     case scm_tc7_contin:
  83       a += 1;
  84       break;
  85     case scm_tc7_subr_2:
  86       a += 2;
  87       break;
  88     case scm_tc7_subr_3:
  89       a += 3;
  90       break;
  91     case scm_tc7_asubr:
  92     case scm_tc7_rpsubr:
  93     case scm_tc7_lsubr:
  94       r = 1;
  95       break;
  96     case scm_tc7_lsubr_2:
  97       a += 2;
  98       r = 1;
  99       break;
 100 #ifdef CCLO
 101     case scm_tc7_cclo:
 102       if (SCM_CCLO_SUBR (proc) == scm_f_gsubr_apply)
 103         {
 104           int type = SCM_INUM (SCM_GSUBR_TYPE (proc));
 105           a += SCM_GSUBR_REQ (type);
 106           o = SCM_GSUBR_OPT (type);
 107           r = SCM_GSUBR_REST (type);
 108           break;
 109         }
 110       proc = SCM_CCLO_SUBR (proc);
 111       a -= 1;
 112       goto loop;
 113 #endif
 114     case scm_tc7_pws:
 115       proc = SCM_PROCEDURE (proc);
 116       goto loop;
 117     case scm_tcs_closures:
 118       proc = SCM_CAR (SCM_CODE (proc));
 119       if (SCM_IMP (proc))
 120         break;
 121       while (SCM_CONSP (proc))
 122         {
 123           ++a;
 124           proc = SCM_CDR (proc);
 125         }
 126       if (SCM_NIMP (proc))
 127         r = 1;
 128       break;
 129     case scm_tcs_cons_gloc:
 130       if (SCM_OBJ_CLASS_FLAGS (proc) & SCM_CLASSF_PURE_GENERIC)
 131         {
 132           r = 1;
 133           break;
 134         }
 135       else if (!SCM_I_OPERATORP (proc))
 136         return SCM_BOOL_F;
 137       proc = (SCM_I_ENTITYP (proc)
 138               ? SCM_ENTITY_PROCEDURE (proc)
 139               : SCM_OPERATOR_PROCEDURE (proc));
 140       a -= 1;
 141       goto loop;
 142     default:
 143       return SCM_BOOL_F;
 144     }
 145   return SCM_LIST3 (SCM_MAKINUM (a),
 146                     SCM_MAKINUM (o),
 147                     SCM_BOOL(r));
 148 }
 149
 150 static SCM
 151 scm_stand_in_scm_proc(SCM proc)
 152 {
 153   SCM answer;
 154   answer = scm_assoc (proc, scm_stand_in_procs);
 155   if (answer == SCM_BOOL_F)
 156     {
 157       answer = scm_closure (scm_listify (SCM_EOL, SCM_BOOL_F, SCM_UNDEFINED),
 158                             SCM_EOL);
 159       scm_stand_in_procs = scm_cons (scm_cons (proc, answer),
 160                                      scm_stand_in_procs);
 161     }
 162   else
 163     answer = SCM_CDR (answer);
 164   return answer;
 165 }
 166
 167 SCM_DEFINE (scm_procedure_properties, "procedure-properties", 1, 0, 0,
 168            (SCM proc),
 169             "Return @var{obj}'s property list.")
 170 #define FUNC_NAME s_scm_procedure_properties
 171 {
 172   SCM_VALIDATE_PROC (1,proc);
 173   return scm_acons (scm_sym_arity, scm_i_procedure_arity (proc),
 174                     SCM_PROCPROPS (SCM_CLOSUREP (proc)
 175                                    ? proc
 176                                    : scm_stand_in_scm_proc (proc)));
 177 }
 178 #undef FUNC_NAME
 179
 180 SCM_DEFINE (scm_set_procedure_properties_x, "set-procedure-properties!", 2, 0, 0,
 181            (SCM proc, SCM new_val),
 182             "Set @var{obj}'s property list to @var{alist}.")
 183 #define FUNC_NAME s_scm_set_procedure_properties_x
 184 {
 185   if (!SCM_CLOSUREP (proc))
 186     proc = scm_stand_in_scm_proc(proc);
 187   SCM_VALIDATE_CLOSURE (1,proc);
 188   SCM_SETPROCPROPS (proc, new_val);
 189   return SCM_UNSPECIFIED;
 190 }
 191 #undef FUNC_NAME
 192
 193 SCM_DEFINE (scm_procedure_property, "procedure-property", 2, 0, 0,
 194            (SCM p, SCM k),
 195             "Return the property of @var{obj} with name @var{key}.")
 196 #define FUNC_NAME s_scm_procedure_property
 197 {
 198   SCM assoc;
 199   if (k == scm_sym_arity)
 200     {
 201       SCM arity;
 202       SCM_ASSERT (SCM_NFALSEP (arity = scm_i_procedure_arity (p)),
 203                   p, SCM_ARG1, FUNC_NAME);
 204       return arity;
 205     }
 206   SCM_VALIDATE_PROC (1,p);
 207   assoc = scm_sloppy_assq (k,
 208                            SCM_PROCPROPS (SCM_CLOSUREP (p)
 209                                           ? p
 210                                           : scm_stand_in_scm_proc (p)));
 211   return (SCM_NIMP (assoc) ? SCM_CDR (assoc) : SCM_BOOL_F);
 212 }
 213 #undef FUNC_NAME
 214
 215 SCM_DEFINE (scm_set_procedure_property_x, "set-procedure-property!", 3, 0, 0,
 216            (SCM p, SCM k, SCM v),
 217             "In @var{obj}'s property list, set the property named @var{key} to\n"
 218             "@var{value}.")
 219 #define FUNC_NAME s_scm_set_procedure_property_x
 220 {
 221   SCM assoc;
 222   if (!SCM_CLOSUREP (p))
 223     p = scm_stand_in_scm_proc(p);
 224   SCM_VALIDATE_CLOSURE (1,p);
 225   if (k == scm_sym_arity)
 226     SCM_MISC_ERROR ("arity is a read-only property", SCM_EOL);
 227   assoc = scm_sloppy_assq (k, SCM_PROCPROPS (p));
 228   if (SCM_NIMP (assoc))
 229     SCM_SETCDR (assoc, v);
 230   else
 231     SCM_SETPROCPROPS (p, scm_acons (k, v, SCM_PROCPROPS (p)));
 232   return SCM_UNSPECIFIED;
 233 }
 234 #undef FUNC_NAME
 235
 236 \f
 237
 238
 239 void
 240 scm_init_procprop ()
 241 {
 242 #include "procprop.x"
 243 }
 244