libguile/gsubr.c

   1 /*      Copyright (C) 1995,1996 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, 675 Mass Ave, Cambridge, MA 02139, USA.
  16  *
  17  * As a special exception, the Free Software Foundation gives permission
  18  * for additional uses of the text contained in its release of GUILE.
  19  *
  20  * The exception is that, if you link the GUILE library with other files
  21  * to produce an executable, this does not by itself cause the
  22  * resulting executable to be covered by the GNU General Public License.
  23  * Your use of that executable is in no way restricted on account of
  24  * linking the GUILE library code into it.
  25  *
  26  * This exception does not however invalidate any other reasons why
  27  * the executable file might be covered by the GNU General Public License.
  28  *
  29  * This exception applies only to the code released by the
  30  * Free Software Foundation under the name GUILE.  If you copy
  31  * code from other Free Software Foundation releases into a copy of
  32  * GUILE, as the General Public License permits, the exception does
  33  * not apply to the code that you add in this way.  To avoid misleading
  34  * anyone as to the status of such modified files, you must delete
  35  * this exception notice from them.
  36  *
  37  * If you write modifications of your own for GUILE, it is your choice
  38  * whether to permit this exception to apply to your modifications.
  39  * If you do not wish that, delete this exception notice.
  40  */
  41 \f
  42
  43 #include <stdio.h>
  44 #include "_scm.h"
  45 #include "genio.h"
  46
  47 #include "gsubr.h"
  48 \f
  49 /*
  50  * gsubr.c
  51  * Provide `gsubrs' -- subrs taking a prescribed number of required, optional,
  52  * and rest arguments.
  53  */
  54
  55 #include "gsubr.h"
  56
  57 #define GSUBR_TEST 1
  58
  59 #define GSUBR_MAKTYPE(req, opt, rst) ((req)|((opt)<<4)|((rst)<<8))
  60 #define GSUBR_REQ(x) ((int)(x)&0xf)
  61 #define GSUBR_OPT(x) (((int)(x)&0xf0)>>4)
  62 #define GSUBR_REST(x) ((int)(x)>>8)
  63
  64 #define GSUBR_MAX 10
  65 #define GSUBR_TYPE(cclo) (SCM_VELTS(cclo)[1])
  66 #define GSUBR_PROC(cclo) (SCM_VELTS(cclo)[2])
  67
  68 static SCM f_gsubr_apply;
  69 #ifdef __STDC__
  70 SCM
  71 scm_make_gsubr(char *name, int req, int opt, int rst, SCM (*fcn)())
  72 #else
  73 SCM
  74 scm_make_gsubr(name, req, opt, rst, fcn)
  75      char *name;
  76      int req;
  77      int opt;
  78      int rst;
  79      SCM (*fcn)();
  80 #endif
  81 {
  82   switch GSUBR_MAKTYPE(req, opt, rst) {
  83   case GSUBR_MAKTYPE(0, 0, 0): return scm_make_subr(name, scm_tc7_subr_0, fcn);
  84   case GSUBR_MAKTYPE(1, 0, 0): return scm_make_subr(name, scm_tc7_subr_1, fcn);
  85   case GSUBR_MAKTYPE(0, 1, 0): return scm_make_subr(name, scm_tc7_subr_1o, fcn);
  86   case GSUBR_MAKTYPE(1, 1, 0): return scm_make_subr(name, scm_tc7_subr_2o, fcn);
  87   case GSUBR_MAKTYPE(2, 0, 0): return scm_make_subr(name, scm_tc7_subr_2, fcn);
  88   case GSUBR_MAKTYPE(3, 0, 0): return scm_make_subr(name, scm_tc7_subr_3, fcn);
  89   case GSUBR_MAKTYPE(0, 0, 1): return scm_make_subr(name, scm_tc7_lsubr, fcn);
  90   case GSUBR_MAKTYPE(2, 0, 1): return scm_make_subr(name, scm_tc7_lsubr_2, fcn);
  91   default:
  92     {
  93       SCM symcell = scm_sysintern(name, SCM_UNDEFINED);
  94       SCM z, cclo = scm_makcclo(f_gsubr_apply, 3L);
  95       long tmp = ((((SCM_CELLPTR)(SCM_CAR(symcell)))-scm_heap_org)<<8);
  96       if (GSUBR_MAX < req + opt + rst) {
  97         fputs("ERROR in scm_make_gsubr: too many args\n", stderr);
  98         exit (1);
  99       }
 100       if ((tmp>>8) != ((SCM_CELLPTR)(SCM_CAR(symcell))-scm_heap_org))
 101         tmp = 0;
 102       SCM_NEWCELL(z);
 103       SCM_SUBRF(z) = fcn;
 104       SCM_CAR(z) = tmp + scm_tc7_subr_0;
 105       GSUBR_PROC(cclo) = z;
 106       GSUBR_TYPE(cclo) = SCM_MAKINUM(GSUBR_MAKTYPE(req, opt, rst));
 107       SCM_CDR(symcell) = cclo;
 108       return cclo;
 109     }
 110   }
 111 }
 112
 113
 114 SCM_PROC(s_gsubr_apply, "gsubr-apply", 0, 0, 1, scm_gsubr_apply);
 115 #ifdef __STDC__
 116 SCM
 117 scm_gsubr_apply(SCM args)
 118 #else
 119 SCM
 120 scm_gsubr_apply(args)
 121      SCM args;
 122 #endif
 123 {
 124   SCM self = SCM_CAR(args);
 125   SCM (*fcn)() = SCM_SUBRF(GSUBR_PROC(self));
 126   SCM v[10];                    /* must agree with greatest supported arity */
 127   int typ = SCM_INUM(GSUBR_TYPE(self));
 128   int i, n = GSUBR_REQ(typ) + GSUBR_OPT(typ) + GSUBR_REST(typ);
 129   args = SCM_CDR(args);
 130   for (i = 0; i < GSUBR_REQ(typ); i++) {
 131 #ifndef RECKLESS
 132     if (SCM_IMP(args))
 133       scm_wta(SCM_UNDEFINED, (char *)SCM_WNA, SCM_CHARS(SCM_SNAME(GSUBR_PROC(self))));
 134 #endif
 135     v[i] = SCM_CAR(args);
 136     args = SCM_CDR(args);
 137   }
 138   for (; i < GSUBR_REQ(typ) + GSUBR_OPT(typ); i++) {
 139     if (SCM_NIMP(args)) {
 140       v[i] = SCM_CAR(args);
 141       args = SCM_CDR(args);
 142     }
 143     else
 144       v[i] = SCM_UNDEFINED;
 145   }
 146   if (GSUBR_REST(typ))
 147     v[i] = args;
 148   switch (n) {
 149   default: scm_wta(self, "internal programming error", s_gsubr_apply);
 150   case 2: return (*fcn)(v[0], v[1]);
 151   case 3: return (*fcn)(v[0], v[1], v[2]);
 152   case 4: return (*fcn)(v[0], v[1], v[2], v[3]);
 153   case 5: return (*fcn)(v[0], v[1], v[2], v[3], v[4]);
 154   case 6: return (*fcn)(v[0], v[1], v[2], v[3], v[4], v[5]);
 155   case 7: return (*fcn)(v[0], v[1], v[2], v[3], v[4], v[5], v[6]);
 156   case 8: return (*fcn)(v[0], v[1], v[2], v[3], v[4], v[5], v[6], v[7]);
 157   case 9: return (*fcn)(v[0], v[1], v[2], v[3], v[4], v[5], v[6], v[7], v[8]);
 158   case 10: return (*fcn)(v[0], v[1], v[2], v[3], v[4], v[5], v[6], v[7], v[8], v[9]);
 159   }
 160 }
 161
 162
 163 #ifdef GSUBR_TEST
 164 /* A silly example, taking 2 required args, 1 optional, and
 165    a scm_list of rest args
 166    */
 167 SCM
 168 gsubr_21l(req1, req2, opt, rst)
 169      SCM req1, req2, opt, rst;
 170 {
 171   scm_gen_puts (scm_regular_string, "gsubr-2-1-l:\n req1: ", scm_cur_outp);
 172   scm_display(req1, scm_cur_outp);
 173   scm_gen_puts (scm_regular_string, "\n req2: ", scm_cur_outp);
 174   scm_display(req2, scm_cur_outp);
 175   scm_gen_puts (scm_regular_string, "\n opt: ", scm_cur_outp);
 176   scm_display(opt, scm_cur_outp);
 177   scm_gen_puts (scm_regular_string, "\n rest: ", scm_cur_outp);
 178   scm_display(rst, scm_cur_outp);
 179   scm_newline(scm_cur_outp);
 180   return SCM_UNSPECIFIED;
 181 }
 182 #endif
 183
 184
 185 #ifdef __STDC__
 186 void
 187 scm_init_gsubr(void)
 188 #else
 189 void
 190 scm_init_gsubr()
 191 #endif
 192 {
 193   f_gsubr_apply = scm_make_subr(s_gsubr_apply, scm_tc7_lsubr, scm_gsubr_apply);
 194 #ifdef GSUBR_TEST
 195   scm_make_gsubr("gsubr-2-1-l", 2, 1, 1, gsubr_21l); /* example */
 196 #endif
 197 }