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 \f
  42
  43 #include <stdio.h>
  44 #include "_scm.h"
  45 #include "alist.h"
  46 #include "eval.h"
  47 #include "procs.h"
  48 #include "gsubr.h"
  49
  50 #include "procprop.h"
  51 \f
  52
  53 SCM_GLOBAL_SYMBOL (scm_sym_arity, "arity");
  54
  55 static SCM
  56 scm_i_procedure_arity (proc)
  57 {
  58   int a = 0, o = 0, r = 0;
  59  loop:
  60   switch (SCM_TYP7 (proc))
  61     {
  62     case scm_tc7_subr_1o:
  63       o = 1;
  64     case scm_tc7_subr_0:
  65       break;
  66     case scm_tc7_subr_2o:
  67       o = 1;
  68     case scm_tc7_subr_1:
  69     case scm_tc7_cxr:
  70     case scm_tc7_contin:
  71       a += 1;
  72       break;
  73     case scm_tc7_subr_2:
  74       a += 2;
  75       break;
  76     case scm_tc7_subr_3:
  77       a += 3;
  78       break;
  79     case scm_tc7_asubr:
  80     case scm_tc7_rpsubr:
  81     case scm_tc7_lsubr:
  82       r = 1;
  83     case scm_tc7_lsubr_2:
  84       a += 2;
  85       break;
  86 #ifdef CCLO
  87     case scm_tc7_cclo:
  88       if (SCM_CCLO_SUBR (proc) == scm_f_gsubr_apply)
  89         {
  90           int type = SCM_INUM (SCM_GSUBR_TYPE (proc));
  91           a = SCM_GSUBR_REQ (type);
  92           o = SCM_GSUBR_OPT (type);
  93           r = SCM_GSUBR_REST (type);
  94           break;
  95         }
  96       proc = SCM_CCLO_SUBR (proc);
  97       a -= 1;
  98       goto loop;
  99 #endif
 100     case scm_tcs_closures:
 101       proc = SCM_CAR (SCM_CODE (proc));
 102       if (SCM_IMP (proc))
 103         break;
 104       while (SCM_NIMP (proc) && SCM_CONSP (proc))
 105         {
 106           ++a;
 107           proc = SCM_CDR (proc);
 108         }
 109       if (SCM_NIMP (proc))
 110         r = 1;
 111       break;
 112     }
 113   return SCM_LIST3 (SCM_MAKINUM (a),
 114                     SCM_MAKINUM (o),
 115                     r ? SCM_BOOL_T : SCM_BOOL_F);
 116 }
 117
 118 static SCM
 119 scm_stand_in_scm_proc(proc)
 120      SCM proc;
 121 {
 122   SCM answer;
 123   answer = scm_assoc (proc, scm_stand_in_procs);
 124   if (answer == SCM_BOOL_F)
 125     {
 126       answer = scm_closure (scm_listify (SCM_EOL, SCM_BOOL_F, SCM_UNDEFINED),
 127                             SCM_EOL);
 128       scm_stand_in_procs = scm_cons (scm_cons (proc, answer),
 129                                      scm_stand_in_procs);
 130     }
 131   else
 132     answer = SCM_CDR (answer);
 133   return answer;
 134 }
 135
 136 SCM_PROC(s_procedure_properties, "procedure-properties", 1, 0, 0, scm_procedure_properties);
 137
 138 SCM
 139 scm_procedure_properties (proc)
 140      SCM proc;
 141 {
 142   SCM_ASSERT (SCM_NFALSEP (scm_procedure_p (proc)),
 143               proc, SCM_ARG1, s_procedure_properties);
 144   return scm_acons (scm_sym_arity, scm_i_procedure_arity (proc),
 145                     SCM_PROCPROPS (SCM_NIMP (proc) && SCM_CLOSUREP (proc)
 146                                    ? proc
 147                                    : scm_stand_in_scm_proc (proc)));
 148 }
 149
 150 SCM_PROC(s_set_procedure_properties_x, "set-procedure-properties!", 2, 0, 0, scm_set_procedure_properties_x);
 151
 152 SCM
 153 scm_set_procedure_properties_x (proc, new_val)
 154      SCM proc;
 155      SCM new_val;
 156 {
 157   if (!(SCM_NIMP (proc) && SCM_CLOSUREP (proc)))
 158     proc = scm_stand_in_scm_proc(proc);
 159   SCM_ASSERT (SCM_NIMP (proc) && SCM_CLOSUREP (proc), proc, SCM_ARG1, s_set_procedure_properties_x);
 160   SCM_SETPROCPROPS (proc, new_val);
 161   return SCM_UNSPECIFIED;
 162 }
 163
 164 SCM_PROC(s_procedure_property, "procedure-property", 2, 0, 0, scm_procedure_property);
 165
 166 SCM
 167 scm_procedure_property (p, k)
 168      SCM p;
 169      SCM k;
 170 {
 171   SCM assoc;
 172   SCM_ASSERT (SCM_NFALSEP (scm_procedure_p (p)),
 173               p, SCM_ARG1, s_procedure_property);
 174   if (k == scm_sym_arity)
 175     return scm_i_procedure_arity (p);
 176   assoc = scm_sloppy_assq (k,
 177                            SCM_PROCPROPS (SCM_NIMP (p) && SCM_CLOSUREP (p)
 178                                           ? p
 179                                           : scm_stand_in_scm_proc (p)));
 180   return (SCM_NIMP (assoc) ? SCM_CDR (assoc) : SCM_BOOL_F);
 181 }
 182
 183 SCM_PROC(s_set_procedure_property_x, "set-procedure-property!", 3, 0, 0, scm_set_procedure_property_x);
 184
 185 SCM
 186 scm_set_procedure_property_x (p, k, v)
 187      SCM p;
 188      SCM k;
 189      SCM v;
 190 {
 191   SCM assoc;
 192   if (!(SCM_NIMP (p) && SCM_CLOSUREP (p)))
 193     p = scm_stand_in_scm_proc(p);
 194   SCM_ASSERT (SCM_NIMP (p) && SCM_CLOSUREP (p), p, SCM_ARG1, s_set_procedure_property_x);
 195   if (k == scm_sym_arity)
 196     scm_misc_error (s_set_procedure_property_x,
 197                     "arity is a read-only property",
 198                     SCM_EOL);
 199   assoc = scm_sloppy_assq (k, SCM_PROCPROPS (p));
 200   if (SCM_NIMP (assoc))
 201     SCM_SETCDR (assoc, v);
 202   else
 203     SCM_SETPROCPROPS (p, scm_acons (k, v, SCM_PROCPROPS (p)));
 204   return SCM_UNSPECIFIED;
 205 }
 206
 207 \f
 208
 209
 210 void
 211 scm_init_procprop ()
 212 {
 213 #include "procprop.x"
 214 }
 215