libguile/procs.c

   1 /* Copyright (C) 1995,1996,1997,1999,2000,2001, 2006, 2008, 2009 Free Software Foundation, Inc.
   2  *
   3  * This library is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU Lesser General Public
   5  * License as published by the Free Software Foundation; either
   6  * version 2.1 of the License, or (at your option) any later version.
   7  *
   8  * This library 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 GNU
  11  * Lesser General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public
  14  * License along with this library; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  16  */
  17
  18
  19 \f
  20 #ifdef HAVE_CONFIG_H
  21 # include <config.h>
  22 #endif
  23
  24 #include "libguile/_scm.h"
  25
  26 #include "libguile/objects.h"
  27 #include "libguile/strings.h"
  28 #include "libguile/vectors.h"
  29 #include "libguile/smob.h"
  30 #include "libguile/deprecation.h"
  31
  32 #include "libguile/validate.h"
  33 #include "libguile/procs.h"
  34 #include "libguile/procprop.h"
  35 #include "libguile/objcodes.h"
  36 #include "libguile/programs.h"
  37 \f
  38
  39
  40 /* {Procedures}
  41  */
  42
  43
  44 SCM
  45 scm_c_make_subr (const char *name, long type, SCM (*fcn) ())
  46 {
  47   register SCM z;
  48   SCM *meta_info;
  49
  50   meta_info = scm_gc_malloc (2 * sizeof (*meta_info), "subr meta-info");
  51   meta_info[0] = scm_from_locale_symbol (name);
  52   meta_info[1] = SCM_EOL;  /* properties */
  53
  54   z = scm_double_cell ((scm_t_bits) type, (scm_t_bits) fcn,
  55                        0 /* generic */, (scm_t_bits) meta_info);
  56
  57   return z;
  58 }
  59
  60 SCM
  61 scm_c_define_subr (const char *name, long type, SCM (*fcn) ())
  62 {
  63   SCM subr = scm_c_make_subr (name, type, fcn);
  64   scm_define (SCM_SNAME (subr), subr);
  65   return subr;
  66 }
  67
  68 /* This function isn't currently used since subrs are never freed. */
  69 /* *fixme* Need mutex here. */
  70 void
  71 scm_free_subr_entry (SCM subr)
  72 {
  73   scm_gc_free (SCM_SUBR_META_INFO (subr), 2 * sizeof (SCM),
  74                "subr meta-info");
  75 }
  76
  77 SCM
  78 scm_c_make_subr_with_generic (const char *name,
  79                               long type, SCM (*fcn) (), SCM *gf)
  80 {
  81   SCM subr = scm_c_make_subr (name, type, fcn);
  82   SCM_SET_SUBR_GENERIC_LOC (subr, gf);
  83   return subr;
  84 }
  85
  86 SCM
  87 scm_c_define_subr_with_generic (const char *name,
  88                                 long type, SCM (*fcn) (), SCM *gf)
  89 {
  90   SCM subr = scm_c_make_subr_with_generic (name, type, fcn, gf);
  91   scm_define (SCM_SNAME (subr), subr);
  92   return subr;
  93 }
  94
  95
  96 SCM_DEFINE (scm_procedure_p, "procedure?", 1, 0, 0,
  97             (SCM obj),
  98             "Return @code{#t} if @var{obj} is a procedure.")
  99 #define FUNC_NAME s_scm_procedure_p
 100 {
 101   if (SCM_NIMP (obj))
 102     switch (SCM_TYP7 (obj))
 103       {
 104       case scm_tcs_struct:
 105         if (!SCM_I_OPERATORP (obj))
 106           break;
 107       case scm_tcs_closures:
 108       case scm_tcs_subrs:
 109       case scm_tc7_pws:
 110         return SCM_BOOL_T;
 111       case scm_tc7_smob:
 112         return scm_from_bool (SCM_SMOB_DESCRIPTOR (obj).apply);
 113       default:
 114         return SCM_BOOL_F;
 115       }
 116   return SCM_BOOL_F;
 117 }
 118 #undef FUNC_NAME
 119
 120 SCM_DEFINE (scm_closure_p, "closure?", 1, 0, 0,
 121            (SCM obj),
 122             "Return @code{#t} if @var{obj} is a closure.")
 123 #define FUNC_NAME s_scm_closure_p
 124 {
 125   return scm_from_bool (SCM_CLOSUREP (obj));
 126 }
 127 #undef FUNC_NAME
 128
 129 SCM_DEFINE (scm_thunk_p, "thunk?", 1, 0, 0,
 130             (SCM obj),
 131             "Return @code{#t} if @var{obj} is a thunk.")
 132 #define FUNC_NAME s_scm_thunk_p
 133 {
 134   if (SCM_NIMP (obj))
 135     {
 136     again:
 137       switch (SCM_TYP7 (obj))
 138         {
 139         case scm_tcs_closures:
 140           return scm_from_bool (!scm_is_pair (SCM_CLOSURE_FORMALS (obj)));
 141         case scm_tc7_subr_0:
 142         case scm_tc7_subr_1o:
 143         case scm_tc7_lsubr:
 144         case scm_tc7_rpsubr:
 145         case scm_tc7_asubr:
 146           return SCM_BOOL_T;
 147         case scm_tc7_gsubr:
 148           return scm_from_bool (SCM_GSUBR_REQ (SCM_GSUBR_TYPE (obj)) == 0);
 149         case scm_tc7_pws:
 150           obj = SCM_PROCEDURE (obj);
 151           goto again;
 152         default:
 153           if (SCM_PROGRAM_P (obj) && SCM_PROGRAM_DATA (obj)->nargs == 0)
 154             return SCM_BOOL_T;
 155           /* otherwise fall through */
 156         }
 157     }
 158   return SCM_BOOL_F;
 159 }
 160 #undef FUNC_NAME
 161
 162 /* Only used internally. */
 163 int
 164 scm_subr_p (SCM obj)
 165 {
 166   if (SCM_NIMP (obj))
 167     switch (SCM_TYP7 (obj))
 168       {
 169       case scm_tcs_subrs:
 170         return 1;
 171       default:
 172         ;
 173       }
 174   return 0;
 175 }
 176
 177 SCM_DEFINE (scm_procedure_documentation, "procedure-documentation", 1, 0, 0,
 178            (SCM proc),
 179             "Return the documentation string associated with @code{proc}.  By\n"
 180             "convention, if a procedure contains more than one expression and the\n"
 181             "first expression is a string constant, that string is assumed to contain\n"
 182             "documentation for that procedure.")
 183 #define FUNC_NAME s_scm_procedure_documentation
 184 {
 185   SCM code;
 186   SCM_ASSERT (scm_is_true (scm_procedure_p (proc)),
 187               proc, SCM_ARG1, FUNC_NAME);
 188   switch (SCM_TYP7 (proc))
 189     {
 190     case scm_tcs_closures:
 191       code = SCM_CLOSURE_BODY (proc);
 192       if (scm_is_null (SCM_CDR (code)))
 193         return SCM_BOOL_F;
 194       code = SCM_CAR (code);
 195       if (scm_is_string (code))
 196         return code;
 197       else
 198         return SCM_BOOL_F;
 199     default:
 200       return SCM_BOOL_F;
 201     }
 202 }
 203 #undef FUNC_NAME
 204
 205
 206 /* Procedure-with-setter
 207  */
 208
 209 SCM_DEFINE (scm_procedure_with_setter_p, "procedure-with-setter?", 1, 0, 0,
 210             (SCM obj),
 211             "Return @code{#t} if @var{obj} is a procedure with an\n"
 212             "associated setter procedure.")
 213 #define FUNC_NAME s_scm_procedure_with_setter_p
 214 {
 215   return scm_from_bool(SCM_PROCEDURE_WITH_SETTER_P (obj));
 216 }
 217 #undef FUNC_NAME
 218
 219 SCM_DEFINE (scm_make_procedure_with_setter, "make-procedure-with-setter", 2, 0, 0,
 220             (SCM procedure, SCM setter),
 221             "Create a new procedure which behaves like @var{procedure}, but\n"
 222             "with the associated setter @var{setter}.")
 223 #define FUNC_NAME s_scm_make_procedure_with_setter
 224 {
 225   SCM name, ret;
 226   SCM_VALIDATE_PROC (1, procedure);
 227   SCM_VALIDATE_PROC (2, setter);
 228   ret = scm_double_cell (scm_tc7_pws,
 229                          SCM_UNPACK (procedure),
 230                          SCM_UNPACK (setter), 0);
 231   /* don't use procedure_name, because don't care enough to do a reverse
 232      lookup */
 233   switch (SCM_TYP7 (procedure)) {
 234   case scm_tcs_subrs:
 235     name = SCM_SNAME (procedure);
 236     break;
 237   default:
 238     name = scm_procedure_property (procedure, scm_sym_name);
 239     break;
 240   }
 241   if (scm_is_true (name))
 242     scm_set_procedure_property_x (ret, scm_sym_name, name);
 243   return ret;
 244 }
 245 #undef FUNC_NAME
 246
 247 SCM_DEFINE (scm_procedure, "procedure", 1, 0, 0,
 248             (SCM proc),
 249             "Return the procedure of @var{proc}, which must be either a\n"
 250             "procedure with setter, or an operator struct.")
 251 #define FUNC_NAME s_scm_procedure
 252 {
 253   SCM_VALIDATE_NIM (1, proc);
 254   if (SCM_PROCEDURE_WITH_SETTER_P (proc))
 255     return SCM_PROCEDURE (proc);
 256   else if (SCM_STRUCTP (proc))
 257     {
 258       SCM_ASSERT (SCM_I_OPERATORP (proc), proc, SCM_ARG1, FUNC_NAME);
 259       return proc;
 260     }
 261   SCM_WRONG_TYPE_ARG (1, proc);
 262   return SCM_BOOL_F; /* not reached */
 263 }
 264 #undef FUNC_NAME
 265
 266 SCM_GPROC (s_setter, "setter", 1, 0, 0, scm_setter, g_setter);
 267
 268 SCM
 269 scm_setter (SCM proc)
 270 {
 271   SCM_GASSERT1 (SCM_NIMP (proc), g_setter, proc, SCM_ARG1, s_setter);
 272   if (SCM_PROCEDURE_WITH_SETTER_P (proc))
 273     return SCM_SETTER (proc);
 274   else if (SCM_STRUCTP (proc))
 275     {
 276       SCM setter;
 277       SCM_GASSERT1 (SCM_I_OPERATORP (proc),
 278                     g_setter, proc, SCM_ARG1, s_setter);
 279       setter = (SCM_I_ENTITYP (proc)
 280                 ? SCM_ENTITY_SETTER (proc)
 281                 : SCM_OPERATOR_SETTER (proc));
 282       if (SCM_NIMP (setter))
 283         return setter;
 284       /* fall through */
 285     }
 286   SCM_WTA_DISPATCH_1 (g_setter, proc, SCM_ARG1, s_setter);
 287   return SCM_BOOL_F; /* not reached */
 288 }
 289
 290 \f
 291 void
 292 scm_init_procs ()
 293 {
 294 #include "libguile/procs.x"
 295 }
 296
 297 /*
 298   Local Variables:
 299   c-file-style: "gnu"
 300   End:
 301 */