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 sname;
  49   SCM *meta_info;
  50
  51   meta_info = scm_gc_malloc (2 * sizeof (*meta_info), "subr meta-info");
  52   sname = scm_from_locale_symbol (name);
  53   meta_info[0] = sname;
  54   meta_info[1] = SCM_EOL;  /* properties */
  55
  56   z = scm_double_cell ((scm_t_bits) type, (scm_t_bits) fcn,
  57                        0 /* generic */, (scm_t_bits) meta_info);
  58
  59   scm_remember_upto_here_1 (sname);
  60
  61   return z;
  62 }
  63
  64 SCM
  65 scm_c_define_subr (const char *name, long type, SCM (*fcn) ())
  66 {
  67   SCM subr = scm_c_make_subr (name, type, fcn);
  68   scm_define (SCM_SNAME (subr), subr);
  69   return subr;
  70 }
  71
  72 /* This function isn't currently used since subrs are never freed. */
  73 /* *fixme* Need mutex here. */
  74 void
  75 scm_free_subr_entry (SCM subr)
  76 {
  77   scm_gc_free (SCM_SUBR_META_INFO (subr), 2 * sizeof (SCM),
  78                "subr meta-info");
  79 }
  80
  81 SCM
  82 scm_c_make_subr_with_generic (const char *name,
  83                               long type, SCM (*fcn) (), SCM *gf)
  84 {
  85   SCM subr = scm_c_make_subr (name, type, fcn);
  86   SCM_SET_SUBR_GENERIC_LOC (subr, gf);
  87   return subr;
  88 }
  89
  90 SCM
  91 scm_c_define_subr_with_generic (const char *name,
  92                                 long type, SCM (*fcn) (), SCM *gf)
  93 {
  94   SCM subr = scm_c_make_subr_with_generic (name, type, fcn, gf);
  95   scm_define (SCM_SNAME (subr), subr);
  96   return subr;
  97 }
  98
  99
 100 SCM_DEFINE (scm_procedure_p, "procedure?", 1, 0, 0,
 101             (SCM obj),
 102             "Return @code{#t} if @var{obj} is a procedure.")
 103 #define FUNC_NAME s_scm_procedure_p
 104 {
 105   if (SCM_NIMP (obj))
 106     switch (SCM_TYP7 (obj))
 107       {
 108       case scm_tcs_struct:
 109         if (!SCM_I_OPERATORP (obj))
 110           break;
 111       case scm_tcs_closures:
 112       case scm_tcs_subrs:
 113       case scm_tc7_pws:
 114         return SCM_BOOL_T;
 115       case scm_tc7_smob:
 116         return scm_from_bool (SCM_SMOB_DESCRIPTOR (obj).apply);
 117       default:
 118         return SCM_BOOL_F;
 119       }
 120   return SCM_BOOL_F;
 121 }
 122 #undef FUNC_NAME
 123
 124 SCM_DEFINE (scm_closure_p, "closure?", 1, 0, 0,
 125            (SCM obj),
 126             "Return @code{#t} if @var{obj} is a closure.")
 127 #define FUNC_NAME s_scm_closure_p
 128 {
 129   return scm_from_bool (SCM_CLOSUREP (obj));
 130 }
 131 #undef FUNC_NAME
 132
 133 SCM_DEFINE (scm_thunk_p, "thunk?", 1, 0, 0,
 134             (SCM obj),
 135             "Return @code{#t} if @var{obj} is a thunk.")
 136 #define FUNC_NAME s_scm_thunk_p
 137 {
 138   if (SCM_NIMP (obj))
 139     {
 140     again:
 141       switch (SCM_TYP7 (obj))
 142         {
 143         case scm_tcs_closures:
 144           return scm_from_bool (!scm_is_pair (SCM_CLOSURE_FORMALS (obj)));
 145         case scm_tc7_subr_0:
 146         case scm_tc7_subr_1o:
 147         case scm_tc7_lsubr:
 148         case scm_tc7_rpsubr:
 149         case scm_tc7_asubr:
 150           return SCM_BOOL_T;
 151         case scm_tc7_gsubr:
 152           return scm_from_bool (SCM_GSUBR_REQ (SCM_GSUBR_TYPE (obj)) == 0);
 153         case scm_tc7_pws:
 154           obj = SCM_PROCEDURE (obj);
 155           goto again;
 156         default:
 157           if (SCM_PROGRAM_P (obj) && SCM_PROGRAM_DATA (obj)->nargs == 0)
 158             return SCM_BOOL_T;
 159           /* otherwise fall through */
 160         }
 161     }
 162   return SCM_BOOL_F;
 163 }
 164 #undef FUNC_NAME
 165
 166 /* Only used internally. */
 167 int
 168 scm_subr_p (SCM obj)
 169 {
 170   if (SCM_NIMP (obj))
 171     switch (SCM_TYP7 (obj))
 172       {
 173       case scm_tcs_subrs:
 174         return 1;
 175       default:
 176         ;
 177       }
 178   return 0;
 179 }
 180
 181 SCM_DEFINE (scm_procedure_documentation, "procedure-documentation", 1, 0, 0,
 182            (SCM proc),
 183             "Return the documentation string associated with @code{proc}.  By\n"
 184             "convention, if a procedure contains more than one expression and the\n"
 185             "first expression is a string constant, that string is assumed to contain\n"
 186             "documentation for that procedure.")
 187 #define FUNC_NAME s_scm_procedure_documentation
 188 {
 189   SCM code;
 190   SCM_ASSERT (scm_is_true (scm_procedure_p (proc)),
 191               proc, SCM_ARG1, FUNC_NAME);
 192   switch (SCM_TYP7 (proc))
 193     {
 194     case scm_tcs_closures:
 195       code = SCM_CLOSURE_BODY (proc);
 196       if (scm_is_null (SCM_CDR (code)))
 197         return SCM_BOOL_F;
 198       code = SCM_CAR (code);
 199       if (scm_is_string (code))
 200         return code;
 201       else
 202         return SCM_BOOL_F;
 203     default:
 204       return SCM_BOOL_F;
 205     }
 206 }
 207 #undef FUNC_NAME
 208
 209
 210 /* Procedure-with-setter
 211  */
 212
 213 SCM_DEFINE (scm_procedure_with_setter_p, "procedure-with-setter?", 1, 0, 0,
 214             (SCM obj),
 215             "Return @code{#t} if @var{obj} is a procedure with an\n"
 216             "associated setter procedure.")
 217 #define FUNC_NAME s_scm_procedure_with_setter_p
 218 {
 219   return scm_from_bool(SCM_PROCEDURE_WITH_SETTER_P (obj));
 220 }
 221 #undef FUNC_NAME
 222
 223 SCM_DEFINE (scm_make_procedure_with_setter, "make-procedure-with-setter", 2, 0, 0,
 224             (SCM procedure, SCM setter),
 225             "Create a new procedure which behaves like @var{procedure}, but\n"
 226             "with the associated setter @var{setter}.")
 227 #define FUNC_NAME s_scm_make_procedure_with_setter
 228 {
 229   SCM name, ret;
 230   SCM_VALIDATE_PROC (1, procedure);
 231   SCM_VALIDATE_PROC (2, setter);
 232   ret = scm_double_cell (scm_tc7_pws,
 233                          SCM_UNPACK (procedure),
 234                          SCM_UNPACK (setter), 0);
 235   /* don't use procedure_name, because don't care enough to do a reverse
 236      lookup */
 237   switch (SCM_TYP7 (procedure)) {
 238   case scm_tcs_subrs:
 239     name = SCM_SNAME (procedure);
 240     break;
 241   default:
 242     name = scm_procedure_property (procedure, scm_sym_name);
 243     break;
 244   }
 245   if (scm_is_true (name))
 246     scm_set_procedure_property_x (ret, scm_sym_name, name);
 247   return ret;
 248 }
 249 #undef FUNC_NAME
 250
 251 SCM_DEFINE (scm_procedure, "procedure", 1, 0, 0,
 252             (SCM proc),
 253             "Return the procedure of @var{proc}, which must be either a\n"
 254             "procedure with setter, or an operator struct.")
 255 #define FUNC_NAME s_scm_procedure
 256 {
 257   SCM_VALIDATE_NIM (1, proc);
 258   if (SCM_PROCEDURE_WITH_SETTER_P (proc))
 259     return SCM_PROCEDURE (proc);
 260   else if (SCM_STRUCTP (proc))
 261     {
 262       SCM_ASSERT (SCM_I_OPERATORP (proc), proc, SCM_ARG1, FUNC_NAME);
 263       return proc;
 264     }
 265   SCM_WRONG_TYPE_ARG (1, proc);
 266   return SCM_BOOL_F; /* not reached */
 267 }
 268 #undef FUNC_NAME
 269
 270 SCM_GPROC (s_setter, "setter", 1, 0, 0, scm_setter, g_setter);
 271
 272 SCM
 273 scm_setter (SCM proc)
 274 {
 275   SCM_GASSERT1 (SCM_NIMP (proc), g_setter, proc, SCM_ARG1, s_setter);
 276   if (SCM_PROCEDURE_WITH_SETTER_P (proc))
 277     return SCM_SETTER (proc);
 278   else if (SCM_STRUCTP (proc))
 279     {
 280       SCM setter;
 281       SCM_GASSERT1 (SCM_I_OPERATORP (proc),
 282                     g_setter, proc, SCM_ARG1, s_setter);
 283       setter = (SCM_I_ENTITYP (proc)
 284                 ? SCM_ENTITY_SETTER (proc)
 285                 : SCM_OPERATOR_SETTER (proc));
 286       if (SCM_NIMP (setter))
 287         return setter;
 288       /* fall through */
 289     }
 290   SCM_WTA_DISPATCH_1 (g_setter, proc, SCM_ARG1, s_setter);
 291   return SCM_BOOL_F; /* not reached */
 292 }
 293
 294 \f
 295 void
 296 scm_init_procs ()
 297 {
 298 #include "libguile/procs.x"
 299 }
 300
 301 /*
 302   Local Variables:
 303   c-file-style: "gnu"
 304   End:
 305 */