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/* Copyright (C) 1995,1996,1997,1998,2000,2001,2003, 2004, 2006 Free Software Foundation, Inc.
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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#include "libguile/_scm.h"
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#include "libguile/ramap.h"
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#include "libguile/stackchk.h"
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#include "libguile/strorder.h"
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#include "libguile/async.h"
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#include "libguile/root.h"
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#include "libguile/smob.h"
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#include "libguile/unif.h"
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#include "libguile/vectors.h"
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#include "libguile/struct.h"
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#include "libguile/goops.h"
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#include "libguile/objects.h"
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#include "libguile/validate.h"
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#include "libguile/eq.h"
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SCM_DEFINE1 (scm_eq_p, "eq?", scm_tc7_rpsubr,
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"Return @code{#t} if @var{x} and @var{y} are the same object,\n"
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"except for numbers and characters. For example,\n"
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"(define x (vector 1 2 3))\n"
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"(define y (vector 1 2 3))\n"
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"(eq? x x) @result{} #t\n"
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"(eq? x y) @result{} #f\n"
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"Numbers and characters are not equal to any other object, but\n"
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"the problem is they're not necessarily @code{eq?} to themselves\n"
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"either. This is even so when the number comes directly from a\n"
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"(let ((n (+ 2 3)))\n"
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" (eq? n n)) @result{} *unspecified*\n"
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"Generally @code{eqv?} should be used when comparing numbers or\n"
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"characters. @code{=} or @code{char=?} can be used too.\n"
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"It's worth noting that end-of-list @code{()}, @code{#t},\n"
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"@code{#f}, a symbol of a given name, and a keyword of a given\n"
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"name, are unique objects. There's just one of each, so for\n"
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"instance no matter how @code{()} arises in a program, it's the\n"
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"same object and can be compared with @code{eq?},\n"
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"(define x (cdr '(123)))\n"
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"(define y (cdr '(456)))\n"
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"(eq? x y) @result{} #t\n"
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"(define x (string->symbol \"foo\"))\n"
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"(eq? x 'foo) @result{} #t\n"
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#define FUNC_NAME s_scm_eq_p
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return scm_from_bool (scm_is_eq (x, y));
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/* We compare doubles in a special way for 'eqv?' to be able to
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distinguish plus and minus zero and to identify NaNs.
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real_eqv (double x, double y)
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return !memcmp (&x, &y, sizeof(double)) || (x != x && y != y);
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SCM_PRIMITIVE_GENERIC_1 (scm_eqv_p, "eqv?", scm_tc7_rpsubr,
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"Return @code{#t} if @var{x} and @var{y} are the same object, or\n"
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"for characters and numbers the same value.\n"
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"On objects except characters and numbers, @code{eqv?} is the\n"
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"same as @code{eq?}, it's true if @var{x} and @var{y} are the\n"
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"If @var{x} and @var{y} are numbers or characters, @code{eqv?}\n"
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"compares their type and value. An exact number is not\n"
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"@code{eqv?} to an inexact number (even if their value is the\n"
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"(eqv? 3 (+ 1 2)) @result{} #t\n"
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"(eqv? 1 1.0) @result{} #f\n"
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#define FUNC_NAME s_scm_eqv_p
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if (scm_is_eq (x, y))
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/* this ensures that types and scm_length are the same. */
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if (SCM_CELL_TYPE (x) != SCM_CELL_TYPE (y))
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/* fractions use 0x10000 as a flag (at the suggestion of Marius Vollmer),
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but this checks the entire type word, so fractions may be accidentally
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flagged here as unequal. Perhaps I should use the 4th double_cell word?
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/* treat mixes of real and complex types specially */
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if (SCM_INEXACTP (x))
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return scm_from_bool (SCM_COMPLEXP (y)
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&& real_eqv (SCM_REAL_VALUE (x),
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SCM_COMPLEX_REAL (y))
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&& SCM_COMPLEX_IMAG (y) == 0.0);
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return scm_from_bool (SCM_REALP (y)
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&& real_eqv (SCM_COMPLEX_REAL (x),
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&& SCM_COMPLEX_IMAG (x) == 0.0);
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if (SCM_FRACTIONP (x) && SCM_FRACTIONP (y))
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return scm_i_fraction_equalp (x, y);
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return scm_from_bool (scm_i_bigcmp (x, y) == 0);
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} else if (SCM_REALP (x)) {
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return scm_from_bool (real_eqv (SCM_REAL_VALUE (x), SCM_REAL_VALUE (y)));
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} else if (SCM_FRACTIONP (x)) {
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return scm_i_fraction_equalp (x, y);
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} else { /* complex */
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return scm_from_bool (real_eqv (SCM_COMPLEX_REAL (x),
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SCM_COMPLEX_REAL (y))
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&& real_eqv (SCM_COMPLEX_IMAG (x),
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SCM_COMPLEX_IMAG (y)));
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if (SCM_UNPACK (g_scm_eqv_p))
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return scm_call_generic_2 (g_scm_eqv_p, x, y);
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SCM_PRIMITIVE_GENERIC_1 (scm_equal_p, "equal?", scm_tc7_rpsubr,
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"Return @code{#t} if @var{x} and @var{y} are the same type, and\n"
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"their contents or value are equal.\n"
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"For a pair, string, vector or array, @code{equal?} compares the\n"
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"contents, and does so using using the same @code{equal?}\n"
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"recursively, so a deep structure can be traversed.\n"
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"(equal? (list 1 2 3) (list 1 2 3)) @result{} #t\n"
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"(equal? (list 1 2 3) (vector 1 2 3)) @result{} #f\n"
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"For other objects, @code{equal?} compares as per @code{eqv?},\n"
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"which means characters and numbers are compared by type and\n"
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"value (and like @code{eqv?}, exact and inexact numbers are not\n"
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"@code{equal?}, even if their value is the same).\n"
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"(equal? 3 (+ 1 2)) @result{} #t\n"
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"(equal? 1 1.0) @result{} #f\n"
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"Hash tables are currently only compared as per @code{eq?}, so\n"
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"two different tables are not @code{equal?}, even if their\n"
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"contents are the same.\n"
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"@code{equal?} does not support circular data structures, it may\n"
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"go into an infinite loop if asked to compare two circular lists\n"
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"New application-defined object types (Smobs) have an\n"
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"@code{equalp} handler which is called by @code{equal?}. This\n"
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"lets an application traverse the contents or control what is\n"
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"considered @code{equal?} for two such objects. If there's no\n"
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"handler, the default is to just compare as per @code{eq?}.")
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#define FUNC_NAME s_scm_equal_p
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if (scm_is_eq (x, y))
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if (scm_is_pair (x) && scm_is_pair (y))
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if (scm_is_false (scm_equal_p (SCM_CAR (x), SCM_CAR (y))))
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if (SCM_TYP7 (x) == scm_tc7_string && SCM_TYP7 (y) == scm_tc7_string)
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return scm_string_equal_p (x, y);
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if (SCM_TYP7 (x) == scm_tc7_smob && SCM_TYP16 (x) == SCM_TYP16 (y))
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int i = SCM_SMOBNUM (x);
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if (!(i < scm_numsmob))
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if (scm_smobs[i].equalp)
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return (scm_smobs[i].equalp) (x, y);
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/* This ensures that types and scm_length are the same. */
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if (SCM_CELL_TYPE (x) != SCM_CELL_TYPE (y))
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/* treat mixes of real and complex types specially */
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if (SCM_INEXACTP (x) && SCM_INEXACTP (y))
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return scm_from_bool (SCM_COMPLEXP (y)
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&& SCM_REAL_VALUE (x) == SCM_COMPLEX_REAL (y)
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&& SCM_COMPLEX_IMAG (y) == 0.0);
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return scm_from_bool (SCM_REALP (y)
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&& SCM_COMPLEX_REAL (x) == SCM_REAL_VALUE (y)
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&& SCM_COMPLEX_IMAG (x) == 0.0);
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/* Vectors can be equal to one-dimensional arrays.
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if (SCM_I_ARRAYP (x) || SCM_I_ARRAYP (y))
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return scm_array_equal_p (x, y);
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switch (SCM_TYP7 (x))
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return scm_bigequal (x, y);
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return scm_real_equalp (x, y);
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case scm_tc16_complex:
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return scm_complex_equalp (x, y);
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case scm_tc16_fraction:
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return scm_i_fraction_equalp (x, y);
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return scm_i_vector_equal_p (x, y);
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/* Check equality between structs of equal type (see cell-type test above)
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that are not GOOPS instances. GOOPS instances are treated via the
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if ((SCM_STRUCTP (x)) && (!SCM_INSTANCEP (x)))
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return scm_i_struct_equalp (x, y);
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if (SCM_UNPACK (g_scm_equal_p))
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return scm_call_generic_2 (g_scm_equal_p, x, y);
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#include "libguile/eq.x"
added
removed
libguile/eq.c
