libguile/values.c

   1 /* Copyright (C) 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 License
   5  * as published by the Free Software Foundation; either version 3 of
   6  * the License, or (at your option) any later version.
   7  *
   8  * This library is distributed in the hope that it will be useful, but
   9  * 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
  16  * 02110-1301 USA
  17  */
  18
  19 #ifdef HAVE_CONFIG_H
  20 # include <config.h>
  21 #endif
  22
  23 #include "libguile/_scm.h"
  24 #include "libguile/eval.h"
  25 #include "libguile/feature.h"
  26 #include "libguile/gc.h"
  27 #include "libguile/numbers.h"
  28 #include "libguile/ports.h"
  29 #include "libguile/root.h"
  30 #include "libguile/strings.h"
  31 #include "libguile/struct.h"
  32 #include "libguile/validate.h"
  33
  34 #include "libguile/values.h"
  35
  36 SCM scm_values_vtable;
  37
  38 static SCM
  39 print_values (SCM obj, SCM pwps)
  40 {
  41   SCM values = scm_struct_ref (obj, SCM_INUM0);
  42   SCM port = SCM_PORT_WITH_PS_PORT (pwps);
  43   scm_print_state *ps = SCM_PRINT_STATE (SCM_PORT_WITH_PS_PS (pwps));
  44
  45   scm_puts ("#<values ", port);
  46   scm_iprin1 (values, port, ps);
  47   scm_puts (">", port);
  48
  49   return SCM_UNSPECIFIED;
  50 }
  51
  52 SCM_DEFINE (scm_values, "values", 0, 0, 1,
  53             (SCM args),
  54             "Delivers all of its arguments to its continuation.  Except for\n"
  55             "continuations created by the @code{call-with-values} procedure,\n"
  56             "all continuations take exactly one value.  The effect of\n"
  57             "passing no value or more than one value to continuations that\n"
  58             "were not created by @code{call-with-values} is unspecified.")
  59 #define FUNC_NAME s_scm_values
  60 {
  61   long n;
  62   SCM result;
  63
  64   SCM_VALIDATE_LIST_COPYLEN (1, args, n);
  65   if (n == 1)
  66     result = SCM_CAR (args);
  67   else
  68     {
  69       result = scm_make_struct (scm_values_vtable, SCM_INUM0,
  70                                 scm_list_1 (args));
  71     }
  72
  73   return result;
  74 }
  75 #undef FUNC_NAME
  76
  77 void
  78 scm_init_values (void)
  79 {
  80   SCM print = scm_c_define_subr ("%print-values", scm_tc7_subr_2,
  81                                  print_values);
  82
  83   scm_values_vtable = scm_make_vtable (scm_from_locale_string ("pr"), print);
  84
  85   scm_add_feature ("values");
  86
  87 #include "libguile/values.x"
  88 }
  89
  90 /*
  91   Local Variables:
  92   c-file-style: "gnu"
  93   End:
  94 */