summaryrefslogtreecommitdiff
path: root/libguile/procprop.c
blob: 2263d283a1c4e6b0536245b429671457b9e45231 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
/* Copyright (C) 1995,1996,1998,2000,2001,2003,2004, 2006, 2008, 2009, 2010 Free Software Foundation, Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 3 of
 * the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */



#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#define SCM_BUILDING_DEPRECATED_CODE

#include "libguile/_scm.h"

#include "libguile/alist.h"
#include "libguile/deprecation.h"
#include "libguile/deprecated.h"
#include "libguile/eval.h"
#include "libguile/procs.h"
#include "libguile/gsubr.h"
#include "libguile/smob.h"
#include "libguile/root.h"
#include "libguile/vectors.h"
#include "libguile/hashtab.h"
#include "libguile/programs.h"

#include "libguile/validate.h"
#include "libguile/procprop.h"


SCM_GLOBAL_SYMBOL (scm_sym_system_procedure, "system-procedure");
#if (SCM_ENABLE_DEPRECATED == 1)
SCM_GLOBAL_SYMBOL (scm_sym_arity, "arity");
#endif
SCM_GLOBAL_SYMBOL (scm_sym_name, "name");

static SCM overrides;
static scm_i_pthread_mutex_t overrides_lock = SCM_I_PTHREAD_MUTEX_INITIALIZER;

int
scm_i_procedure_arity (SCM proc, int *req, int *opt, int *rest)
{
  while (!SCM_PROGRAM_P (proc))
    {
      if (SCM_IMP (proc))
        return 0;
      switch (SCM_TYP7 (proc))
        {
        case scm_tc7_smob:
          if (!SCM_SMOB_APPLICABLE_P (proc))
            return 0;
          proc = scm_i_smob_apply_trampoline (proc);
          break;
        case scm_tcs_struct:
          if (!SCM_STRUCT_APPLICABLE_P (proc))
            return 0;
          proc = SCM_STRUCT_PROCEDURE (proc);
          break;
        default:
          return 0;
        }
    }
  return scm_i_program_arity (proc, req, opt, rest);
}

SCM_DEFINE (scm_procedure_minimum_arity, "procedure-minimum-arity", 1, 0, 0, 
           (SCM proc),
	    "Return the \"minimum arity\" of a procedure.\n\n"
            "If the procedure has only one arity, that arity is returned\n"
            "as a list of three values: the number of required arguments,\n"
            "the number of optional arguments, and a boolean indicating\n"
            "whether or not the procedure takes rest arguments.\n\n"
            "For a case-lambda procedure, the arity returned is the one\n"
            "with the lowest minimum number of arguments, and the highest\n"
            "maximum number of arguments.\n\n"
            "If it was not possible to determine the arity of the procedure,\n"
            "@code{#f} is returned.")
#define FUNC_NAME s_scm_procedure_minimum_arity
{
  int req, opt, rest;
  
  if (scm_i_procedure_arity (proc, &req, &opt, &rest))
    return scm_list_3 (scm_from_int (req),
                       scm_from_int (opt),
                       scm_from_bool (rest));
  else
    return SCM_BOOL_F;
}
#undef FUNC_NAME

SCM_DEFINE (scm_procedure_properties, "procedure-properties", 1, 0, 0, 
           (SCM proc),
	    "Return @var{obj}'s property list.")
#define FUNC_NAME s_scm_procedure_properties
{
  SCM ret;
  
  SCM_VALIDATE_PROC (1, proc);

  scm_i_pthread_mutex_lock (&overrides_lock);
  ret = scm_hashq_ref (overrides, proc, SCM_BOOL_F);
  scm_i_pthread_mutex_unlock (&overrides_lock);

  if (scm_is_false (ret))
    {
      if (SCM_PROGRAM_P (proc))
        ret = scm_i_program_properties (proc);
      else
        ret = SCM_EOL;
    }
  
#if (SCM_ENABLE_DEPRECATED == 1)
  ret = scm_acons (scm_sym_arity, scm_procedure_minimum_arity (proc), ret);
#endif

  return ret;
}
#undef FUNC_NAME

SCM_DEFINE (scm_set_procedure_properties_x, "set-procedure-properties!", 2, 0, 0,
           (SCM proc, SCM alist),
	    "Set @var{proc}'s property list to @var{alist}.")
#define FUNC_NAME s_scm_set_procedure_properties_x
{
  SCM_VALIDATE_PROC (1, proc);

#if (SCM_ENABLE_DEPRECATED == 1)
  if (scm_assq (alist, scm_sym_arity))
    SCM_MISC_ERROR ("arity is a read-only property", SCM_EOL);
#endif

  scm_i_pthread_mutex_lock (&overrides_lock);
  scm_hashq_set_x (overrides, proc, alist);
  scm_i_pthread_mutex_unlock (&overrides_lock);

  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

SCM_DEFINE (scm_procedure_property, "procedure-property", 2, 0, 0,
           (SCM proc, SCM key),
	    "Return the property of @var{proc} with name @var{key}.")
#define FUNC_NAME s_scm_procedure_property
{
  SCM_VALIDATE_PROC (1, proc);

#if (SCM_ENABLE_DEPRECATED == 1)
  if (scm_is_eq (key, scm_sym_arity))
    scm_c_issue_deprecation_warning
      ("Accessing a procedure's arity via `procedure-property' is deprecated.\n"
       "Use `procedure-minimum-arity instead.");
#endif

  return scm_assq_ref (scm_procedure_properties (proc), key);
}
#undef FUNC_NAME

SCM_DEFINE (scm_set_procedure_property_x, "set-procedure-property!", 3, 0, 0,
           (SCM proc, SCM key, SCM val),
	    "In @var{proc}'s property list, set the property named @var{key} to\n"
	    "@var{val}.")
#define FUNC_NAME s_scm_set_procedure_property_x
{
  SCM props;

  SCM_VALIDATE_PROC (1, proc);

#if (SCM_ENABLE_DEPRECATED == 1)
  if (scm_is_eq (key, scm_sym_arity))
    SCM_MISC_ERROR ("arity is a deprecated read-only property", SCM_EOL);
#endif

  props = scm_procedure_properties (proc);

#if (SCM_ENABLE_DEPRECATED == 1)
  /* cdr past the consed-on arity. */
  props = scm_cdr (props);
#endif

  scm_i_pthread_mutex_lock (&overrides_lock);
  scm_hashq_set_x (overrides, proc, scm_assq_set_x (props, key, val));
  scm_i_pthread_mutex_unlock (&overrides_lock);

  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME




void
scm_init_procprop ()
{
  overrides = scm_make_weak_key_hash_table (SCM_UNDEFINED);
#include "libguile/procprop.x"
}


/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/