1 /* Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
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)
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.
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
18 * As a special exception, the Free Software Foundation gives permission
19 * for additional uses of the text contained in its release of GUILE.
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.
27 * This exception does not however invalidate any other reasons why
28 * the executable file might be covered by the GNU General Public License.
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.
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. */
45 #include "libguile/_scm.h"
47 #include "libguile/eval.h"
48 #include "libguile/macros.h"
49 #include "libguile/root.h"
51 #include "libguile/validate.h"
52 #include "libguile/lang.h"
56 /* {Multi-language support}
59 /* Representation of pairs:
61 * Since we're going to share data with Scheme, we use EOL instead of nil
62 * in all data structures.
65 #ifdef SCM_ENABLE_ELISP
68 SCM_DEFINE (scm_nil_cons
, "nil-cons", 2, 0, 0,
70 "Create a new cons cell with @var{x} as the car and @var{y} as\n"
71 "the cdr, but convert @var{y} to Scheme's end-of-list if it is\n"
73 #define FUNC_NAME s_scm_nil_cons
75 return scm_cons (x
, SCM_NIL2EOL (y
, y
));
80 SCM_DEFINE (scm_nil_car
, "nil-car", 1, 0, 0,
82 "Return the car of @var{x}, but convert it to LISP nil if it\n"
83 "is Scheme's end-of-list.")
84 #define FUNC_NAME s_scm_nil_car
88 SCM_VALIDATE_CONS (1,x
);
93 SCM_DEFINE (scm_nil_cdr
, "nil-cdr", 1, 0, 0,
95 "Return the cdr of @var{x}, but convert it to LISP nil if it\n"
96 "is Scheme's end-of-list.")
97 #define FUNC_NAME s_scm_nil_cdr
101 SCM_VALIDATE_CONS (1,x
);
102 return SCM_EOL2NIL (SCM_CDR (x
), x
);
106 /* GJB:FIXME:: why does this return scm_lisp_nil instead of SCM_BOOL_F?
107 Could use SCM_BOOL, below, otherwise */
108 SCM_DEFINE (scm_null
, "null", 1, 0, 0,
110 "Return LISP's @code{t} if @var{x} is nil in the LISP sense,\n"
111 "return LISP's nil otherwise.")
112 #define FUNC_NAME s_scm_null
114 return (SCM_NILP (x
) || SCM_NULLP (x
) || SCM_FALSEP (x
)) ? scm_lisp_t
: scm_lisp_nil
;
119 scm_m_while (SCM exp
, SCM env
)
121 register SCM x
= exp
= SCM_CDR (exp
);
122 SCM z
= scm_eval_car (x
, env
);
123 while (!SCM_NILP (z
) && SCM_NFALSEP (z
))
125 while (SCM_NNULLP (x
= SCM_CDR (x
)))
127 if (SCM_NIMP (SCM_CAR (x
)))
128 (*scm_ceval_ptr
) (SCM_CAR (x
), env
);
130 z
= scm_eval_car (x
= exp
, env
);
135 /* GJB:FIXME:: why does this return scm_lisp_nil instead of SCM_BOOL_F?
136 Could use SCM_BOOL, below, otherwise */
137 SCM_DEFINE1 (scm_nil_eq
, "nil-eq", scm_tc7_rpsubr
,
139 "Compare @var{x} and @var{y} and return LISP's t if they are\n"
140 "@code{eq?}, return LISP's nil otherwise.")
141 #define FUNC_NAME s_scm_nil_eq
143 return ((SCM_EQ_P (x
, y
)
144 || (SCM_NILP (x
) && (SCM_NULLP (y
) || SCM_FALSEP (y
)))
145 || (SCM_NILP (y
) && (SCM_NULLP (x
) || SCM_FALSEP (x
))))
158 #ifndef SCM_MAGIC_SNARFER
159 #include "libguile/lang.x"
161 scm_make_synt ("nil-while", scm_makacro
, scm_m_while
);
164 scm_c_define ("%nil", SCM_ELISP_NIL
);
167 #endif /* SCM_ENABLE_ELISP */