| 1 | /* Copyright (C) 1995,1996,1997,1998,2000,2001, 2006, 2008, 2011 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 | |
| 20 | \f |
| 21 | #ifdef HAVE_CONFIG_H |
| 22 | # include <config.h> |
| 23 | #endif |
| 24 | |
| 25 | #include "libguile/_scm.h" |
| 26 | #include "libguile/eq.h" |
| 27 | #include "libguile/ports.h" |
| 28 | #include "libguile/root.h" |
| 29 | #include "libguile/smob.h" |
| 30 | #include "libguile/deprecation.h" |
| 31 | |
| 32 | #include "libguile/validate.h" |
| 33 | #include "libguile/variable.h" |
| 34 | \f |
| 35 | |
| 36 | void |
| 37 | scm_i_variable_print (SCM exp, SCM port, scm_print_state *pstate) |
| 38 | { |
| 39 | scm_puts ("#<variable ", port); |
| 40 | scm_uintprint (SCM_UNPACK (exp), 16, port); |
| 41 | scm_puts (" value: ", port); |
| 42 | scm_iprin1 (SCM_VARIABLE_REF (exp), port, pstate); |
| 43 | scm_putc('>', port); |
| 44 | } |
| 45 | |
| 46 | \f |
| 47 | |
| 48 | static SCM |
| 49 | make_variable (SCM init) |
| 50 | { |
| 51 | return scm_cell (scm_tc7_variable, SCM_UNPACK (init)); |
| 52 | } |
| 53 | |
| 54 | SCM_DEFINE (scm_make_variable, "make-variable", 1, 0, 0, |
| 55 | (SCM init), |
| 56 | "Return a variable initialized to value @var{init}.") |
| 57 | #define FUNC_NAME s_scm_make_variable |
| 58 | { |
| 59 | return make_variable (init); |
| 60 | } |
| 61 | #undef FUNC_NAME |
| 62 | |
| 63 | |
| 64 | SCM_DEFINE (scm_make_undefined_variable, "make-undefined-variable", 0, 0, 0, |
| 65 | (), |
| 66 | "Return a variable that is initially unbound.") |
| 67 | #define FUNC_NAME s_scm_make_undefined_variable |
| 68 | { |
| 69 | return make_variable (SCM_UNDEFINED); |
| 70 | } |
| 71 | #undef FUNC_NAME |
| 72 | |
| 73 | |
| 74 | SCM_DEFINE (scm_variable_p, "variable?", 1, 0, 0, |
| 75 | (SCM obj), |
| 76 | "Return @code{#t} iff @var{obj} is a variable object, else\n" |
| 77 | "return @code{#f}.") |
| 78 | #define FUNC_NAME s_scm_variable_p |
| 79 | { |
| 80 | return scm_from_bool (SCM_VARIABLEP (obj)); |
| 81 | } |
| 82 | #undef FUNC_NAME |
| 83 | |
| 84 | |
| 85 | SCM_DEFINE (scm_variable_ref, "variable-ref", 1, 0, 0, |
| 86 | (SCM var), |
| 87 | "Dereference @var{var} and return its value.\n" |
| 88 | "@var{var} must be a variable object; see @code{make-variable}\n" |
| 89 | "and @code{make-undefined-variable}.") |
| 90 | #define FUNC_NAME s_scm_variable_ref |
| 91 | { |
| 92 | SCM val; |
| 93 | SCM_VALIDATE_VARIABLE (1, var); |
| 94 | val = SCM_VARIABLE_REF (var); |
| 95 | if (scm_is_eq (val, SCM_UNDEFINED)) |
| 96 | SCM_MISC_ERROR ("variable is unbound: ~S", scm_list_1 (var)); |
| 97 | return val; |
| 98 | } |
| 99 | #undef FUNC_NAME |
| 100 | |
| 101 | SCM_DEFINE (scm_variable_set_x, "variable-set!", 2, 0, 0, |
| 102 | (SCM var, SCM val), |
| 103 | "Set the value of the variable @var{var} to @var{val}.\n" |
| 104 | "@var{var} must be a variable object, @var{val} can be any\n" |
| 105 | "value. Return an unspecified value.") |
| 106 | #define FUNC_NAME s_scm_variable_set_x |
| 107 | { |
| 108 | SCM_VALIDATE_VARIABLE (1, var); |
| 109 | SCM_VARIABLE_SET (var, val); |
| 110 | return SCM_UNSPECIFIED; |
| 111 | } |
| 112 | #undef FUNC_NAME |
| 113 | |
| 114 | SCM_DEFINE (scm_variable_unset_x, "variable-unset!", 1, 0, 0, |
| 115 | (SCM var), |
| 116 | "Ensure that @var{var} is not bound to a value.\n" |
| 117 | "@var{var} must be a variable object.") |
| 118 | #define FUNC_NAME s_scm_variable_unset_x |
| 119 | { |
| 120 | SCM_VALIDATE_VARIABLE (1, var); |
| 121 | SCM_VARIABLE_SET (var, SCM_UNDEFINED); |
| 122 | return SCM_UNSPECIFIED; |
| 123 | } |
| 124 | #undef FUNC_NAME |
| 125 | |
| 126 | SCM_DEFINE (scm_variable_bound_p, "variable-bound?", 1, 0, 0, |
| 127 | (SCM var), |
| 128 | "Return @code{#t} iff @var{var} is bound to a value.\n" |
| 129 | "Throws an error if @var{var} is not a variable object.") |
| 130 | #define FUNC_NAME s_scm_variable_bound_p |
| 131 | { |
| 132 | SCM_VALIDATE_VARIABLE (1, var); |
| 133 | return scm_from_bool (!scm_is_eq (SCM_VARIABLE_REF (var), SCM_UNDEFINED)); |
| 134 | } |
| 135 | #undef FUNC_NAME |
| 136 | |
| 137 | |
| 138 | void |
| 139 | scm_init_variable () |
| 140 | { |
| 141 | #include "libguile/variable.x" |
| 142 | } |
| 143 | |
| 144 | /* |
| 145 | Local Variables: |
| 146 | c-file-style: "gnu" |
| 147 | End: |
| 148 | */ |