-/* Copyright (C) 1995,1996,1997,1998, 2000 Free Software Foundation, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * This program 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this software; see the file COPYING. If not, write to
- * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
- * Boston, MA 02111-1307 USA
- *
- * As a special exception, the Free Software Foundation gives permission
- * for additional uses of the text contained in its release of GUILE.
- *
- * The exception is that, if you link the GUILE library with other files
- * to produce an executable, this does not by itself cause the
- * resulting executable to be covered by the GNU General Public License.
- * Your use of that executable is in no way restricted on account of
- * linking the GUILE library code into it.
- *
- * This exception does not however invalidate any other reasons why
- * the executable file might be covered by the GNU General Public License.
- *
- * This exception applies only to the code released by the
- * Free Software Foundation under the name GUILE. If you copy
- * code from other Free Software Foundation releases into a copy of
- * GUILE, as the General Public License permits, the exception does
- * not apply to the code that you add in this way. To avoid misleading
- * anyone as to the status of such modified files, you must delete
- * this exception notice from them.
- *
- * If you write modifications of your own for GUILE, it is your choice
- * whether to permit this exception to apply to your modifications.
- * If you do not wish that, delete this exception notice. */
-
-/* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
- gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
-
-\f
-#include <stdio.h>
-#include "libguile/_scm.h"
-#include "libguile/ramap.h"
-#include "libguile/stackchk.h"
-#include "libguile/strorder.h"
-#include "libguile/async.h"
-#include "libguile/root.h"
-#include "libguile/smob.h"
-#include "libguile/unif.h"
-#include "libguile/vectors.h"
-
-#include "libguile/validate.h"
-#include "libguile/eq.h"
-\f
-SCM_DEFINE1 (scm_eq_p, "eq?", scm_tc7_rpsubr,
- (SCM x, SCM y),
- "Return #t iff X references the same object as Y.\n"
- "`eq?' is similar to `eqv?' except that in some cases\n"
- "it is capable of discerning distinctions finer than\n"
- "those detectable by `eqv?'.\n")
-#define FUNC_NAME s_scm_eq_p
-{
- return SCM_BOOL (SCM_EQ_P (x, y));
-}
-#undef FUNC_NAME
-
-
-SCM_DEFINE1 (scm_eqv_p, "eqv?", scm_tc7_rpsubr,
- (SCM x, SCM y),
- "The `eqv?' procedure defines a useful equivalence relation on objects.\n"
- "Briefly, it returns #t if X and Y should normally be\n"
- "regarded as the same object. This relation is left\n"
- "slightly open to interpretation, but works for comparing\n"
- "immediate integers, characters, and inexact numbers.\n")
-#define FUNC_NAME s_scm_eqv_p
-{
- if (SCM_EQ_P (x, y))
- return SCM_BOOL_T;
- if (SCM_IMP (x))
- return SCM_BOOL_F;
- if (SCM_IMP (y))
- return SCM_BOOL_F;
- /* this ensures that types and scm_length are the same. */
- if (SCM_CELL_TYPE (x) != SCM_CELL_TYPE (y))
- {
- /* treat mixes of real and complex types specially */
- if (SCM_SLOPPY_INEXACTP (x))
- {
- if (SCM_SLOPPY_REALP (x))
- return SCM_BOOL (SCM_SLOPPY_COMPLEXP (y)
- && SCM_REAL_VALUE (x) == SCM_COMPLEX_REAL (y)
- && 0.0 == SCM_COMPLEX_IMAG (y));
- else
- return SCM_BOOL (SCM_SLOPPY_REALP (y)
- && SCM_COMPLEX_REAL (x) == SCM_REAL_VALUE (y)
- && SCM_COMPLEX_IMAG (x) == 0.0);
- }
- return SCM_BOOL_F;
- }
- if (SCM_NUMP (x))
- {
-# ifdef SCM_BIGDIG
- if (SCM_BIGP (x))
- return SCM_BOOL (0 == scm_bigcomp (x, y));
-# endif
- if (SCM_REALPART (x) != SCM_REALPART(y)) return SCM_BOOL_F;
- if (SCM_CPLXP(x) && (SCM_IMAG(x) != SCM_IMAG(y))) return SCM_BOOL_F;
- return SCM_BOOL_T;
- }
- return SCM_BOOL_F;
-}
-#undef FUNC_NAME
-
-
-SCM_DEFINE1 (scm_equal_p, "equal?", scm_tc7_rpsubr,
- (SCM x, SCM y),
- "Return #t iff X and Y are recursively `eqv?' equivalent.\n"
- "`equal?' recursively compares the contents of pairs, vectors, and\n"
- "strings, applying `eqv?' on other objects such as numbers and\n"
- "symbols. A rule of thumb is that objects are generally `equal?'\n"
- "if they print the same. `Equal?' may fail to terminate if its\n"
- "arguments are circular data structures.\n")
-#define FUNC_NAME s_scm_equal_p
-{
- SCM_CHECK_STACK;
- tailrecurse:
- SCM_TICK;
- if (SCM_EQ_P (x, y))
- return SCM_BOOL_T;
- if (SCM_IMP (x))
- return SCM_BOOL_F;
- if (SCM_IMP (y))
- return SCM_BOOL_F;
- if (SCM_SLOPPY_CONSP (x) && SCM_SLOPPY_CONSP (y))
- {
- if (SCM_FALSEP (scm_equal_p (SCM_CAR (x), SCM_CAR (y))))
- return SCM_BOOL_F;
- x = SCM_CDR(x);
- y = SCM_CDR(y);
- goto tailrecurse;
- }
- if (SCM_TYP7S (x) == scm_tc7_string && SCM_TYP7S (y) == scm_tc7_string)
- return scm_string_equal_p (x, y);
- /* This ensures that types and scm_length are the same. */
- if (SCM_CELL_TYPE (x) != SCM_CELL_TYPE (y))
- {
- /* treat mixes of real and complex types specially */
- if (SCM_SLOPPY_INEXACTP (x))
- {
- if (SCM_SLOPPY_REALP (x))
- return SCM_BOOL (SCM_SLOPPY_COMPLEXP (y)
- && SCM_REAL_VALUE (x) == SCM_COMPLEX_REAL (y)
- && 0.0 == SCM_COMPLEX_IMAG (y));
- else
- return SCM_BOOL (SCM_SLOPPY_REALP (y)
- && SCM_COMPLEX_REAL (x) == SCM_REAL_VALUE (y)
- && SCM_COMPLEX_IMAG (x) == 0.0);
- }
- return SCM_BOOL_F;
- }
- switch (SCM_TYP7 (x))
- {
- default:
- return SCM_BOOL_F;
- case scm_tc7_vector:
- case scm_tc7_wvect:
- return scm_vector_equal_p (x, y);
- case scm_tc7_smob:
- {
- int i = SCM_SMOBNUM (x);
- if (!(i < scm_numsmob))
- return SCM_BOOL_F;
- if (scm_smobs[i].equalp)
- return (scm_smobs[i].equalp) (x, y);
- else
- return SCM_BOOL_F;
- }
-#ifdef HAVE_ARRAYS
- case scm_tc7_bvect: case scm_tc7_uvect: case scm_tc7_ivect:
- case scm_tc7_fvect: case scm_tc7_cvect: case scm_tc7_dvect:
- case scm_tc7_svect:
-#ifdef HAVE_LONG_LONGS
- case scm_tc7_llvect:
-#endif
- case scm_tc7_byvect:
- if (scm_tc16_array && scm_smobs[0x0ff & (scm_tc16_array >> 8)].equalp)
- return scm_array_equal_p (x, y);
-#endif
- }
- return SCM_BOOL_F;
-}
-#undef FUNC_NAME
-
-
-\f
-
-
-
-void
-scm_init_eq ()
-{
-#include "libguile/eq.x"
-}
-
-
-/*
- Local Variables:
- c-file-style: "gnu"
- End:
-*/
+/* Copyright (C) 1995,1996,1997,1998,2000,2001,2003, 2004, 2006, 2009, 2010, 2011 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
+ */
+
+\f
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <math.h>
+
+#include "libguile/_scm.h"
+#include "libguile/array-map.h"
+#include "libguile/stackchk.h"
+#include "libguile/strorder.h"
+#include "libguile/async.h"
+#include "libguile/root.h"
+#include "libguile/smob.h"
+#include "libguile/arrays.h"
+#include "libguile/vectors.h"
+#include "libguile/hashtab.h"
+#include "libguile/bytevectors.h"
+
+#include "libguile/struct.h"
+#include "libguile/goops.h"
+
+#include "libguile/validate.h"
+#include "libguile/eq.h"
+
+#include "libguile/private-options.h"
+
+\f
+
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+\f
+
+static SCM scm_i_eq_p (SCM x, SCM y, SCM rest);
+SCM_DEFINE (scm_i_eq_p, "eq?", 0, 2, 1,
+ (SCM x, SCM y, SCM rest),
+ "Return @code{#t} if @var{x} and @var{y} are the same object,\n"
+ "except for numbers and characters. For example,\n"
+ "\n"
+ "@example\n"
+ "(define x (vector 1 2 3))\n"
+ "(define y (vector 1 2 3))\n"
+ "\n"
+ "(eq? x x) @result{} #t\n"
+ "(eq? x y) @result{} #f\n"
+ "@end example\n"
+ "\n"
+ "Numbers and characters are not equal to any other object, but\n"
+ "the problem is they're not necessarily @code{eq?} to themselves\n"
+ "either. This is even so when the number comes directly from a\n"
+ "variable,\n"
+ "\n"
+ "@example\n"
+ "(let ((n (+ 2 3)))\n"
+ " (eq? n n)) @result{} *unspecified*\n"
+ "@end example\n"
+ "\n"
+ "Generally @code{eqv?} should be used when comparing numbers or\n"
+ "characters. @code{=} or @code{char=?} can be used too.\n"
+ "\n"
+ "It's worth noting that end-of-list @code{()}, @code{#t},\n"
+ "@code{#f}, a symbol of a given name, and a keyword of a given\n"
+ "name, are unique objects. There's just one of each, so for\n"
+ "instance no matter how @code{()} arises in a program, it's the\n"
+ "same object and can be compared with @code{eq?},\n"
+ "\n"
+ "@example\n"
+ "(define x (cdr '(123)))\n"
+ "(define y (cdr '(456)))\n"
+ "(eq? x y) @result{} #t\n"
+ "\n"
+ "(define x (string->symbol \"foo\"))\n"
+ "(eq? x 'foo) @result{} #t\n"
+ "@end example")
+#define FUNC_NAME s_scm_i_eq_p
+{
+ if (SCM_UNBNDP (x) || SCM_UNBNDP (y))
+ return SCM_BOOL_T;
+ while (scm_is_pair (rest))
+ {
+ if (!scm_is_eq (x, y))
+ return SCM_BOOL_F;
+ x = y;
+ y = scm_car (rest);
+ rest = scm_cdr (rest);
+ }
+ return scm_from_bool (scm_is_eq (x, y));
+}
+#undef FUNC_NAME
+
+SCM
+scm_eq_p (SCM x, SCM y)
+{
+ return scm_from_bool (scm_is_eq (x, y));
+}
+
+/* We compare doubles in a special way for 'eqv?' to be able to
+ distinguish plus and minus zero and to identify NaNs.
+*/
+
+static int
+real_eqv (double x, double y)
+{
+ return !memcmp (&x, &y, sizeof(double))
+ || (SCM_UNLIKELY (isnan (x)) && SCM_UNLIKELY (isnan (y)));
+}
+
+SCM
+scm_real_equalp (SCM x, SCM y)
+{
+ return scm_from_bool (real_eqv (SCM_REAL_VALUE (x),
+ SCM_REAL_VALUE (y)));
+}
+
+SCM
+scm_bigequal (SCM x, SCM y)
+{
+ return scm_from_bool (scm_i_bigcmp (x, y) == 0);
+}
+
+SCM
+scm_complex_equalp (SCM x, SCM y)
+{
+ return scm_from_bool (real_eqv (SCM_COMPLEX_REAL (x),
+ SCM_COMPLEX_REAL (y))
+ && real_eqv (SCM_COMPLEX_IMAG (x),
+ SCM_COMPLEX_IMAG (y)));
+}
+
+SCM
+scm_i_fraction_equalp (SCM x, SCM y)
+{
+ return scm_from_bool
+ (scm_is_true (scm_equal_p (SCM_FRACTION_NUMERATOR (x),
+ SCM_FRACTION_NUMERATOR (y)))
+ && scm_is_true (scm_equal_p (SCM_FRACTION_DENOMINATOR (x),
+ SCM_FRACTION_DENOMINATOR (y))));
+}
+
+static SCM scm_i_eqv_p (SCM x, SCM y, SCM rest);
+#include <stdio.h>
+SCM_DEFINE (scm_i_eqv_p, "eqv?", 0, 2, 1,
+ (SCM x, SCM y, SCM rest),
+ "Return @code{#t} if @var{x} and @var{y} are the same object, or\n"
+ "for characters and numbers the same value.\n"
+ "\n"
+ "On objects except characters and numbers, @code{eqv?} is the\n"
+ "same as @code{eq?}, it's true if @var{x} and @var{y} are the\n"
+ "same object.\n"
+ "\n"
+ "If @var{x} and @var{y} are numbers or characters, @code{eqv?}\n"
+ "compares their type and value. An exact number is not\n"
+ "@code{eqv?} to an inexact number (even if their value is the\n"
+ "same).\n"
+ "\n"
+ "@example\n"
+ "(eqv? 3 (+ 1 2)) @result{} #t\n"
+ "(eqv? 1 1.0) @result{} #f\n"
+ "@end example")
+#define FUNC_NAME s_scm_i_eqv_p
+{
+ if (SCM_UNBNDP (x) || SCM_UNBNDP (y))
+ return SCM_BOOL_T;
+ while (!scm_is_null (rest))
+ {
+ if (!scm_is_true (scm_eqv_p (x, y)))
+ return SCM_BOOL_F;
+ x = y;
+ y = scm_car (rest);
+ rest = scm_cdr (rest);
+ }
+ return scm_eqv_p (x, y);
+}
+#undef FUNC_NAME
+
+SCM scm_eqv_p (SCM x, SCM y)
+#define FUNC_NAME s_scm_i_eqv_p
+{
+ if (scm_is_eq (x, y))
+ return SCM_BOOL_T;
+ if (SCM_IMP (x))
+ return SCM_BOOL_F;
+ if (SCM_IMP (y))
+ return SCM_BOOL_F;
+
+ /* this ensures that types and scm_length are the same. */
+ if (SCM_CELL_TYPE (x) != SCM_CELL_TYPE (y))
+ return SCM_BOOL_F;
+ switch (SCM_TYP7 (x))
+ {
+ default:
+ break;
+ case scm_tc7_number:
+ switch SCM_TYP16 (x)
+ {
+ case scm_tc16_big:
+ return scm_bigequal (x, y);
+ case scm_tc16_real:
+ return scm_real_equalp (x, y);
+ case scm_tc16_complex:
+ return scm_complex_equalp (x, y);
+ case scm_tc16_fraction:
+ return scm_i_fraction_equalp (x, y);
+ }
+ }
+ return SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+
+static SCM scm_i_equal_p (SCM, SCM, SCM);
+SCM_PRIMITIVE_GENERIC (scm_i_equal_p, "equal?", 0, 2, 1,
+ (SCM x, SCM y, SCM rest),
+ "Return @code{#t} if @var{x} and @var{y} are the same type, and\n"
+ "their contents or value are equal.\n"
+ "\n"
+ "For a pair, string, vector or array, @code{equal?} compares the\n"
+ "contents, and does so using using the same @code{equal?}\n"
+ "recursively, so a deep structure can be traversed.\n"
+ "\n"
+ "@example\n"
+ "(equal? (list 1 2 3) (list 1 2 3)) @result{} #t\n"
+ "(equal? (list 1 2 3) (vector 1 2 3)) @result{} #f\n"
+ "@end example\n"
+ "\n"
+ "For other objects, @code{equal?} compares as per @code{eqv?},\n"
+ "which means characters and numbers are compared by type and\n"
+ "value (and like @code{eqv?}, exact and inexact numbers are not\n"
+ "@code{equal?}, even if their value is the same).\n"
+ "\n"
+ "@example\n"
+ "(equal? 3 (+ 1 2)) @result{} #t\n"
+ "(equal? 1 1.0) @result{} #f\n"
+ "@end example\n"
+ "\n"
+ "Hash tables are currently only compared as per @code{eq?}, so\n"
+ "two different tables are not @code{equal?}, even if their\n"
+ "contents are the same.\n"
+ "\n"
+ "@code{equal?} does not support circular data structures, it may\n"
+ "go into an infinite loop if asked to compare two circular lists\n"
+ "or similar.\n"
+ "\n"
+ "New application-defined object types (Smobs) have an\n"
+ "@code{equalp} handler which is called by @code{equal?}. This\n"
+ "lets an application traverse the contents or control what is\n"
+ "considered @code{equal?} for two such objects. If there's no\n"
+ "handler, the default is to just compare as per @code{eq?}.")
+#define FUNC_NAME s_scm_i_equal_p
+{
+ if (SCM_UNBNDP (x) || SCM_UNBNDP (y))
+ return SCM_BOOL_T;
+ while (!scm_is_null (rest))
+ {
+ if (!scm_is_true (scm_equal_p (x, y)))
+ return SCM_BOOL_F;
+ x = y;
+ y = scm_car (rest);
+ rest = SCM_CDR (rest);
+ }
+ return scm_equal_p (x, y);
+}
+#undef FUNC_NAME
+
+SCM
+scm_equal_p (SCM x, SCM y)
+#define FUNC_NAME s_scm_i_equal_p
+{
+ SCM_CHECK_STACK;
+ tailrecurse:
+ SCM_TICK;
+ if (scm_is_eq (x, y))
+ return SCM_BOOL_T;
+ if (SCM_IMP (x))
+ return SCM_BOOL_F;
+ if (SCM_IMP (y))
+ return SCM_BOOL_F;
+ if (scm_is_pair (x) && scm_is_pair (y))
+ {
+ if (scm_is_false (scm_equal_p (SCM_CAR (x), SCM_CAR (y))))
+ return SCM_BOOL_F;
+ x = SCM_CDR(x);
+ y = SCM_CDR(y);
+ goto tailrecurse;
+ }
+ if (SCM_TYP7 (x) == scm_tc7_string && SCM_TYP7 (y) == scm_tc7_string)
+ return scm_string_equal_p (x, y);
+ if (SCM_TYP7 (x) == scm_tc7_bytevector && SCM_TYP7 (y) == scm_tc7_bytevector)
+ return scm_bytevector_eq_p (x, y);
+ if (SCM_TYP7 (x) == scm_tc7_smob && SCM_TYP16 (x) == SCM_TYP16 (y))
+ {
+ int i = SCM_SMOBNUM (x);
+ if (!(i < scm_numsmob))
+ return SCM_BOOL_F;
+ if (scm_smobs[i].equalp)
+ return (scm_smobs[i].equalp) (x, y);
+ else
+ goto generic_equal;
+ }
+ if (SCM_POINTER_P (x) && SCM_POINTER_P (y))
+ return scm_from_bool (SCM_POINTER_VALUE (x) == SCM_POINTER_VALUE (y));
+
+ /* This ensures that types and scm_length are the same. */
+ if (SCM_CELL_TYPE (x) != SCM_CELL_TYPE (y))
+ {
+ /* Vectors can be equal to one-dimensional arrays.
+ */
+ if (scm_is_array (x) && scm_is_array (y))
+ return scm_array_equal_p (x, y);
+
+ return SCM_BOOL_F;
+ }
+ switch (SCM_TYP7 (x))
+ {
+ default:
+ /* Check equality between structs of equal type (see cell-type test above). */
+ if (SCM_STRUCTP (x))
+ {
+ if (SCM_INSTANCEP (x))
+ goto generic_equal;
+ else
+ return scm_i_struct_equalp (x, y);
+ }
+ break;
+ case scm_tc7_number:
+ switch SCM_TYP16 (x)
+ {
+ case scm_tc16_big:
+ return scm_bigequal (x, y);
+ case scm_tc16_real:
+ return scm_real_equalp (x, y);
+ case scm_tc16_complex:
+ return scm_complex_equalp (x, y);
+ case scm_tc16_fraction:
+ return scm_i_fraction_equalp (x, y);
+ }
+ case scm_tc7_vector:
+ case scm_tc7_wvect:
+ return scm_i_vector_equal_p (x, y);
+ }
+
+ /* Otherwise just return false. Dispatching to the generic is the wrong thing
+ here, as we can hit this case for any two objects of the same type that we
+ think are distinct, like different symbols. */
+ return SCM_BOOL_F;
+
+ generic_equal:
+ if (SCM_UNPACK (g_scm_i_equal_p))
+ return scm_call_2 (g_scm_i_equal_p, x, y);
+ else
+ return SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+
+\f
+
+
+
+void
+scm_init_eq ()
+{
+#include "libguile/eq.x"
+}
+
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/