libguile/macros.c

   1 /*      Copyright (C) 1995,1996,1997,1998 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 "_scm.h"
  48 #include "smob.h"
  49
  50 #include "scm_validate.h"
  51 #include "macros.h"
  52
  53 long scm_tc16_macro;
  54
  55 SCM_DEFINE (scm_makacro, "procedure->syntax", 1, 0, 0,
  56             (SCM code),
  57 "")
  58 #define FUNC_NAME s_scm_makacro
  59 {
  60   SCM_VALIDATE_PROC(1,code);
  61   SCM_RETURN_NEWSMOB (scm_tc16_macro, code);
  62 }
  63 #undef FUNC_NAME
  64
  65
  66 SCM_DEFINE(scm_makmacro, "procedure->macro", 1, 0, 0,
  67            (SCM code),
  68 "")
  69 #define FUNC_NAME s_scm_makmacro
  70 {
  71   SCM_VALIDATE_PROC(1,code);
  72   SCM_RETURN_NEWSMOB (scm_tc16_macro | (1L << 16), code);
  73 }
  74 #undef FUNC_NAME
  75
  76
  77 SCM_DEFINE(scm_makmmacro, "procedure->memoizing-macro", 1, 0, 0,
  78            (SCM code),
  79 "")
  80 #define FUNC_NAME s_scm_makmmacro
  81 {
  82   SCM_VALIDATE_PROC(1,code);
  83   SCM_RETURN_NEWSMOB (scm_tc16_macro | (2L << 16), code);
  84 }
  85 #undef FUNC_NAME
  86
  87
  88 SCM_DEFINE (scm_macro_p, "macro?", 1, 0, 0,
  89             (SCM obj),
  90 "Return @code{#t} if @var{obj} is a regular macro, a memoizing macro or a
  91 syntax transformer.")
  92 #define FUNC_NAME s_scm_macro_p
  93 {
  94   return SCM_BOOL(SCM_NIMP (obj) && SCM_TYP16 (obj) == scm_tc16_macro);
  95 }
  96 #undef FUNC_NAME
  97
  98
  99 SCM_SYMBOL (scm_sym_syntax, "syntax");
 100 SCM_SYMBOL (scm_sym_macro, "macro");
 101 SCM_SYMBOL (scm_sym_mmacro, "macro!");
 102
 103 SCM_DEFINE (scm_macro_type, "macro-type", 1, 0, 0,
 104             (SCM m),
 105 "Return one of the symbols @code{syntax}, @code{macro} or @code{macro!},
 106 depending on whether @var{obj} is a syntax tranformer, a regular macro,
 107 or a memoizing macro, respectively.  If @var{obj} is not a macro,
 108 @code{#f} is returned.")
 109 #define FUNC_NAME s_scm_macro_type
 110 {
 111   if (!(SCM_NIMP (m) && SCM_TYP16 (m) == scm_tc16_macro))
 112     return SCM_BOOL_F;
 113   switch ((int) (SCM_CAR (m) >> 16))
 114     {
 115     case 0: return scm_sym_syntax;
 116     case 1: return scm_sym_macro;
 117     case 2: return scm_sym_mmacro;
 118     default: scm_wrong_type_arg (FUNC_NAME, 1, m);
 119     }
 120 }
 121 #undef FUNC_NAME
 122
 123
 124 SCM_DEFINE (scm_macro_name, "macro-name", 1, 0, 0,
 125             (SCM m),
 126 "")
 127 #define FUNC_NAME s_scm_macro_name
 128 {
 129   SCM_VALIDATE_SMOB(1,m,macro);
 130   return scm_procedure_name (SCM_CDR (m));
 131 }
 132 #undef FUNC_NAME
 133
 134
 135 SCM_DEFINE (scm_macro_transformer, "macro-transformer", 1, 0, 0,
 136             (SCM m),
 137 "")
 138 #define FUNC_NAME s_scm_macro_transformer
 139 {
 140   SCM_VALIDATE_SMOB(1,m,macro);
 141   return SCM_CLOSUREP (SCM_CDR (m)) ? SCM_CDR (m) : SCM_BOOL_F;
 142 }
 143 #undef FUNC_NAME
 144
 145 SCM
 146 scm_make_synt (const char *name, SCM (*macroizer) (), SCM (*fcn)() )
 147 {
 148   SCM symcell = scm_sysintern (name, SCM_UNDEFINED);
 149   SCM transformer = scm_make_subr_opt (name, scm_tc7_subr_2, fcn, 0);
 150   SCM_SETCDR (symcell, macroizer (transformer));
 151   return SCM_CAR (symcell);
 152 }
 153
 154 void
 155 scm_init_macros ()
 156 {
 157   scm_tc16_macro = scm_make_smob_type_mfpe ("macro", 0,
 158                                            scm_markcdr, NULL, NULL, NULL);
 159 #include "macros.x"
 160 }