This repository has been archived on 2023-08-20. You can view files and clone it, but cannot push or open issues or pull requests.
yap-6.3/C/cmppreds.c
Vítor Santos Costa 8eec3113be improve docs
2014-09-15 03:13:50 -05:00

936 lines
20 KiB
C

/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: cmppreds.c *
* Last rev: *
* mods: *
* comments: comparing two prolog terms *
* *
*************************************************************************/
/// @file cmppreds.c
/** @defgroup Comparing_Terms Comparing Terms
@ingroup YAPBuiltins
The following predicates are used to compare and order terms, using the
standard ordering:
+
variables come before numbers, numbers come before atoms which in turn
come before compound terms, i.e.: variables @< numbers @< atoms @<
compound terms.
+
Variables are roughly ordered by "age" (the "oldest" variable is put
first);
+
Floating point numbers are sorted in increasing order;
+
Rational numbers are sorted in increasing order;
+
Integers are sorted in increasing order;
+
Atoms are sorted in lexicographic order;
+
Compound terms are ordered first by arity of the main functor, then by
the name of the main functor, and finally by their arguments in
left-to-right order.
@{
*/
#ifdef SCCS
static char SccsId[] = "%W% %G%";
#endif
#include "Yap.h"
#include "Yatom.h"
#include "YapHeap.h"
#include "eval.h"
#if HAVE_STRING_H
#include <string.h>
#endif
#include <wchar.h>
static Int compare(Term, Term);
static Int p_compare( USES_REGS1 );
static Int p_acomp( USES_REGS1 );
static Int a_eq(Term,Term);
static Int a_dif(Term,Term);
static Int a_gt(Term, Term);
static Int a_ge(Term,Term);
static Int a_lt(Term,Term);
static Int a_le(Term,Term);
static Int a_noteq(Term,Term);
static Int a_gen_lt(Term,Term);
static Int a_gen_le(Term,Term);
static Int a_gen_gt(Term,Term);
static Int a_gen_ge(Term,Term);
#define rfloat(X) ( X > 0.0 ? 1 : ( X == 0.0 ? 0 : -1))
static int
cmp_atoms(Atom a1, Atom a2)
{
if (IsWideAtom(a1)) {
if (IsWideAtom(a2)) {
return wcscmp((wchar_t *)RepAtom(a1)->StrOfAE,(wchar_t *)RepAtom(a2)->StrOfAE);
} else {
/* The standard does not seem to have nothing on this */
unsigned char *s1 = (unsigned char *)RepAtom(a1)->StrOfAE;
wchar_t *s2 = (wchar_t *)RepAtom(a2)->StrOfAE;
while (*s1 == *s2) {
if (!*s1) return 0;
s1++;
s2++;
}
return *s1-*s2;
}
} else if (IsWideAtom(a2)) {
/* The standard does not seem to have nothing on this */
wchar_t *s1 = (wchar_t *)RepAtom(a1)->StrOfAE;
unsigned char *s2 = (unsigned char *)RepAtom(a2)->StrOfAE;
while (*s1 == *s2) {
if (!*s1) return 0;
s1++;
s2++;
}
return *s1-*s2;
} else {
return strcmp(RepAtom(a1)->StrOfAE,RepAtom(a2)->StrOfAE);
}
}
static int compare_complex(register CELL *pt0, register CELL *pt0_end, register
CELL *pt1)
{
CACHE_REGS
register CELL **to_visit = (CELL **)HR;
register int out = 0;
loop:
while (pt0 < pt0_end) {
register CELL d0, d1;
++ pt0;
++ pt1;
d0 = Derefa(pt0);
d1 = Derefa(pt1);
if (IsVarTerm(d0)) {
if (IsVarTerm(d1)) {
out = Signed(d0) - Signed(d1);
if (out) goto done;
}
else {
out = -1;
goto done;
}
} else if (IsVarTerm(d1)) {
out = 1;
goto done;
} else {
if (d0 == d1) continue;
else if (IsAtomTerm(d0)) {
if (IsAtomTerm(d1))
out = cmp_atoms(AtomOfTerm(d0), AtomOfTerm(d1));
else if (IsPrimitiveTerm(d1))
out = 1;
else out = -1;
/* I know out must be != 0 */
goto done;
}
else if (IsIntTerm(d0)) {
if (IsIntTerm(d1))
out = IntOfTerm(d0) - IntOfTerm(d1);
else if (IsFloatTerm(d1)) {
out = 1;
} else if (IsLongIntTerm(d1)) {
out = IntOfTerm(d0) - LongIntOfTerm(d1);
#ifdef USE_GMP
} else if (IsBigIntTerm(d1)) {
out = Yap_gmp_tcmp_int_big(IntOfTerm(d0), d1);
#endif
} else if (IsRefTerm(d1))
out = 1 ;
else out = -1;
if (out != 0)
goto done;
} else if (IsFloatTerm(d0)) {
if (IsFloatTerm(d1)){
out = rfloat(FloatOfTerm(d0) - FloatOfTerm(d1));
} else if (IsRefTerm(d1)) {
out = 1;
} else {
out = -1;
}
if (out != 0)
goto done;
} else if (IsStringTerm(d0)) {
if (IsStringTerm(d1)){
out = strcmp(StringOfTerm(d0) , StringOfTerm(d1));
} else if (IsIntTerm(d1))
out = 1;
else if (IsFloatTerm(d1)) {
out = 1;
} else if (IsLongIntTerm(d1)) {
out = 1;
#ifdef USE_GMP
} else if (IsBigIntTerm(d1)) {
out = 1;
#endif
} else if (IsRefTerm(d1)) {
out = 1 ;
} else {
out = -1;
}
if (out != 0)
goto done;
} else if (IsLongIntTerm(d0)) {
if (IsIntTerm(d1))
out = LongIntOfTerm(d0) - IntOfTerm(d1);
else if (IsFloatTerm(d1)) {
out = 1;
} else if (IsLongIntTerm(d1)) {
out = LongIntOfTerm(d0) - LongIntOfTerm(d1);
#ifdef USE_GMP
} else if (IsBigIntTerm(d1)) {
out = Yap_gmp_tcmp_int_big(LongIntOfTerm(d0), d1);
#endif
} else if (IsRefTerm(d1)) {
out = 1 ;
} else {
out = -1;
}
if (out != 0)
goto done;
}
#ifdef USE_GMP
else if (IsBigIntTerm(d0)) {
if (IsIntTerm(d1)) {
out = Yap_gmp_tcmp_int_big(d0, IntOfTerm(d1));
} else if (IsFloatTerm(d1)) {
out = 1;
} else if (IsLongIntTerm(d1)) {
out = Yap_gmp_tcmp_int_big(d0, LongIntOfTerm(d1));
} else if (IsBigIntTerm(d1)) {
out = Yap_gmp_tcmp_big_big(d0, d1);
} else if (IsRefTerm(d1))
out = 1 ;
else out = -1;
if (out != 0)
goto done;
}
#endif
else if (IsPairTerm(d0)) {
if (!IsPairTerm(d1)) {
if (IsApplTerm(d1)) {
Functor f = FunctorOfTerm(d1);
if (IsExtensionFunctor(f))
out = 1;
else if (!(out = 2-ArityOfFunctor(f)))
out = strcmp(".",RepAtom(NameOfFunctor(f))->StrOfAE);
} else out = 1;
goto done;
}
#ifdef RATIONAL_TREES
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = (CELL *)*pt0;
to_visit += 4;
*pt0 = d1;
#else
/* store the terms to visit */
if (pt0 < pt0_end) {
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit += 3;
}
#endif
pt0 = RepPair(d0) - 1;
pt0_end = RepPair(d0) + 1;
pt1 = RepPair(d1) - 1;
continue;
}
else if (IsRefTerm(d0)) {
if (IsRefTerm(d1))
out = Unsigned(RefOfTerm(d1)) -
Unsigned(RefOfTerm(d0));
else out = -1;
goto done;
} else if (IsApplTerm(d0)) {
register Functor f;
register CELL *ap2, *ap3;
if (!IsApplTerm(d1)) {
out = 1 ;
goto done;
} else {
/* store the terms to visit */
Functor f2;
ap2 = RepAppl(d0);
ap3 = RepAppl(d1);
f = (Functor)(*ap2);
if (IsExtensionFunctor(f)) {
out = 1;
goto done;
}
f2 = (Functor)(*ap3);
if (IsExtensionFunctor(f2)) {
out = -1;
goto done;
}
/* compare functors */
if (f != (Functor)*ap3) {
if (!(out = ArityOfFunctor(f)-ArityOfFunctor(f2)))
out = cmp_atoms(NameOfFunctor(f), NameOfFunctor(f2));
goto done;
}
#ifdef RATIONAL_TREES
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = (CELL *)*pt0;
to_visit += 4;
*pt0 = d1;
#else
/* store the terms to visit */
if (pt0 < pt0_end) {
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit += 3;
}
#endif
d0 = ArityOfFunctor(f);
pt0 = ap2;
pt0_end = ap2 + d0;
pt1 = ap3;
continue;
}
}
}
}
/* Do we still have compound terms to visit */
if (to_visit > (CELL **)HR) {
#ifdef RATIONAL_TREES
to_visit -= 4;
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
*pt0 = (CELL)to_visit[3];
#else
to_visit -= 3;
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
#endif
goto loop;
}
done:
/* failure */
#ifdef RATIONAL_TREES
while (to_visit > (CELL **)HR) {
to_visit -= 4;
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
*pt0 = (CELL)to_visit[3];
}
#endif
return(out);
}
inline static Int
compare(Term t1, Term t2) /* compare terms t1 and t2 */
{
if (t1 == t2)
return 0;
if (IsVarTerm(t1)) {
if (IsVarTerm(t2))
return Signed(t1) - Signed(t2);
return -1;
} else if (IsVarTerm(t2)) {
/* get rid of variables */
return 1;
}
if (IsAtomOrIntTerm(t1)) {
if (IsAtomTerm(t1)) {
if (IsAtomTerm(t2))
return cmp_atoms(AtomOfTerm(t1),AtomOfTerm(t2));
if (IsPrimitiveTerm(t2))
return 1;
if (IsStringTerm(t2))
return 1;
return -1;
} else {
if (IsIntTerm(t2)) {
return IntOfTerm(t1) - IntOfTerm(t2);
}
if (IsApplTerm(t2)) {
Functor fun2 = FunctorOfTerm(t2);
switch ((CELL)fun2) {
case double_e:
return 1;
case long_int_e:
return IntOfTerm(t1) - LongIntOfTerm(t2);
#ifdef USE_GMP
case big_int_e:
return Yap_gmp_tcmp_int_big(IntOfTerm(t1), t2);
#endif
case db_ref_e:
return 1;
case string_e:
return -1;
}
}
return -1;
}
} else if (IsPairTerm(t1)) {
if (IsApplTerm(t2)) {
Functor f = FunctorOfTerm(t2);
if (IsExtensionFunctor(f))
return 1;
else {
int out;
if (!(out = 2-ArityOfFunctor(f)))
out = strcmp(".",RepAtom(NameOfFunctor(f))->StrOfAE);
return(out);
}
}
if (IsPairTerm(t2)) {
return(compare_complex(RepPair(t1)-1,
RepPair(t1)+1,
RepPair(t2)-1));
}
else return 1;
} else {
/* compound term */
Functor fun1 = FunctorOfTerm(t1);
if (IsExtensionFunctor(fun1)) {
/* float, long, big, dbref */
switch ((CELL)fun1) {
case double_e:
{
if (IsFloatTerm(t2))
return(rfloat(FloatOfTerm(t1) - FloatOfTerm(t2)));
if (IsRefTerm(t2))
return 1;
return -1;
}
case long_int_e:
{
if (IsIntTerm(t2))
return LongIntOfTerm(t1) - IntOfTerm(t2);
if (IsFloatTerm(t2)) {
return 1;
}
if (IsLongIntTerm(t2))
return LongIntOfTerm(t1) - LongIntOfTerm(t2);
#ifdef USE_GMP
if (IsBigIntTerm(t2)) {
return Yap_gmp_tcmp_int_big(LongIntOfTerm(t1), t2);
}
#endif
if (IsRefTerm(t2))
return 1;
return -1;
}
#ifdef USE_GMP
case big_int_e:
{
if (IsIntTerm(t2))
return Yap_gmp_tcmp_big_int(t1, IntOfTerm(t2));
if (IsFloatTerm(t2)) {
return 1;
}
if (IsLongIntTerm(t2))
return Yap_gmp_tcmp_big_int(t1, LongIntOfTerm(t2));
if (IsBigIntTerm(t2)) {
return Yap_gmp_tcmp_big_big(t1, t2);
}
if (IsRefTerm(t2))
return 1;
return -1;
}
#endif
case string_e:
{
if (IsApplTerm(t2)) {
Functor fun2 = FunctorOfTerm(t2);
switch ((CELL)fun2) {
case double_e:
return 1;
case long_int_e:
return 1;
#ifdef USE_GMP
case big_int_e:
return 1;
#endif
case db_ref_e:
return 1;
case string_e:
return strcmp(StringOfTerm(t1), StringOfTerm(t2));
}
return -1;
}
return -1;
}
case db_ref_e:
if (IsRefTerm(t2))
return Unsigned(RefOfTerm(t2)) -
Unsigned(RefOfTerm(t1));
return -1;
}
}
if (!IsApplTerm(t2)) {
if (IsPairTerm(t2)) {
Int out;
Functor f = FunctorOfTerm(t1);
if (!(out = ArityOfFunctor(f))-2)
out = strcmp(RepAtom(NameOfFunctor(f))->StrOfAE,".");
return out;
}
return 1;
} else {
Functor fun2 = FunctorOfTerm(t2);
Int r;
if (IsExtensionFunctor(fun2)) {
return 1;
}
r = ArityOfFunctor(fun1) - ArityOfFunctor(fun2);
if (r)
return r;
r = cmp_atoms(NameOfFunctor(fun1), NameOfFunctor(fun2));
if (r)
return r;
else
return(compare_complex(RepAppl(t1),
RepAppl(t1)+ArityOfFunctor(fun1),
RepAppl(t2)));
}
}
}
Int Yap_compare_terms(Term d0, Term d1)
{
return compare(Deref(d0),Deref(d1));
}
/** @pred compare( _C_, _X_, _Y_) is iso
As a result of comparing _X_ and _Y_, _C_ may take one of
the following values:
+
`=` if _X_ and _Y_ are identical;
+
`<` if _X_ precedes _Y_ in the defined order;
+
`>` if _Y_ precedes _X_ in the defined order;
*/
Int
p_compare( USES_REGS1 )
{ /* compare(?Op,?T1,?T2) */
Int r = compare(Deref(ARG2), Deref(ARG3));
Atom p;
if (r < 0)
p = AtomLT;
else if (r > 0)
p = AtomGT;
else
p = AtomEQ;
return Yap_unify_constant(ARG1, MkAtomTerm(p));
}
/** @pred _X_ \== _Y_ is iso
Terms _X_ and _Y_ are not strictly identical.
*/
static Int
a_noteq(Term t1, Term t2)
{
return (compare(t1, t2) != 0);
}
static Int
a_gen_lt(Term t1, Term t2)
{
return (compare(t1, t2) < 0);
}
/** @pred _X_ @=< _Y_ is iso
Term _X_ does not follow term _Y_ in the standard order.
*/
static Int
a_gen_le(Term t1, Term t2)
{
return (compare(t1, t2) <= 0);
}
/** @pred _X_ @> _Y_ is iso
Term _X_ does not follow term _Y_ in the standard order
*/
static Int
a_gen_gt(Term t1, Term t2)
{
return compare(t1, t2) > 0;
}
/** @pred _X_ @>= _Y_ is iso
Term _X_ does not precede term _Y_ in the standard order.
*/
static Int
a_gen_ge(Term t1, Term t2)
{
return compare(t1, t2) >= 0;
}
/**
@}
*/
/**
@defgroup arithmetic_cmps Arithmetic Comparison Predicates
@ingroup arithmetic
Comparison of Numeric Expressions. Both arguments must be valid ground expressions at time of call.
@{
*/
inline static Int
int_cmp(Int dif)
{
return dif;
}
inline static Int
flt_cmp(Float dif)
{
if (dif < 0.0)
return -1;
if (dif > 0.0)
return 1;
return dif = 0.0;
}
static inline Int
a_cmp(Term t1, Term t2 USES_REGS)
{
LOCAL_ArithError = FALSE;
if (IsVarTerm(t1)) {
LOCAL_ArithError = TRUE;
Yap_Error(INSTANTIATION_ERROR, t1, "=:=/2");
return FALSE;
}
if (IsVarTerm(t2)) {
LOCAL_ArithError = TRUE;
Yap_Error(INSTANTIATION_ERROR, t2, "=:=/2");
return FALSE;
}
if (IsFloatTerm(t1) && IsFloatTerm(t2)) {
return flt_cmp(FloatOfTerm(t1)-FloatOfTerm(t2));
}
if (IsIntegerTerm(t1) && IsIntegerTerm(t2)) {
return int_cmp(IntegerOfTerm(t1)-IntegerOfTerm(t2));
}
t1 = Yap_Eval(t1);
if (!t1) {
return FALSE;
}
if (IsIntegerTerm(t1)) {
Int i1 = IntegerOfTerm(t1);
t2 = Yap_Eval(t2);
if (IsIntegerTerm(t2)) {
Int i2 = IntegerOfTerm(t2);
return int_cmp(i1-i2);
} else if (IsFloatTerm(t2)) {
Float f2 = FloatOfTerm(t2);
#if HAVE_ISNAN
if (isnan(f2)) {
LOCAL_Error_TYPE = EVALUATION_ERROR_UNDEFINED;
LOCAL_Error_Term = t2;
LOCAL_ErrorMessage = "trying to evaluate nan";
LOCAL_ArithError = TRUE;
}
#endif
return flt_cmp(i1-f2);
#ifdef USE_GMP
} else if (IsBigIntTerm(t2)) {
return Yap_gmp_cmp_int_big(i1,t2);
#endif
} else {
return FALSE;
}
} else if (IsFloatTerm(t1)) {
Float f1 = FloatOfTerm(t1);
#if HAVE_ISNAN
if (isnan(f1)) {
LOCAL_Error_TYPE = EVALUATION_ERROR_UNDEFINED;
LOCAL_Error_Term = t1;
LOCAL_ErrorMessage = "trying to evaluate nan";
LOCAL_ArithError = TRUE;
}
#endif
t2 = Yap_Eval(t2);
#if HAVE_ISNAN
if (isnan(f1))
return -1;
#endif
if (IsIntegerTerm(t2)) {
Int i2 = IntegerOfTerm(t2);
return flt_cmp(f1-i2);
} else if (IsFloatTerm(t2)) {
Float f2 = FloatOfTerm(t2);
#if HAVE_ISNAN
if (isnan(f2)) {
LOCAL_Error_TYPE = EVALUATION_ERROR_UNDEFINED;
LOCAL_Error_Term = t2;
LOCAL_ErrorMessage = "trying to evaluate nan";
LOCAL_ArithError = TRUE;
}
#endif
return flt_cmp(f1-f2);
#ifdef USE_GMP
} else if (IsBigIntTerm(t2)) {
return Yap_gmp_cmp_float_big(f1,t2);
#endif
} else {
return FALSE;
}
#ifdef USE_GMP
} else if (IsBigIntTerm(t1)) {
{
t2 = Yap_Eval(t2);
if (IsIntegerTerm(t2)) {
return Yap_gmp_cmp_big_int(t1, IntegerOfTerm(t2));
} else if (IsFloatTerm(t2)) {
Float f2 = FloatOfTerm(t2);
#if HAVE_ISNAN
if (isnan(f2)) {
LOCAL_Error_TYPE = EVALUATION_ERROR_UNDEFINED;
LOCAL_Error_Term = t2;
LOCAL_ErrorMessage = "trying to evaluate nan";
LOCAL_ArithError = TRUE;
}
#endif
return Yap_gmp_cmp_big_float(t1, f2);
} else if (IsBigIntTerm(t2)) {
return Yap_gmp_cmp_big_big(t1, t2);
} else {
return FALSE;
}
}
#endif
} else {
return FALSE;
}
}
Int
Yap_acmp(Term t1, Term t2 USES_REGS)
{
Int out = a_cmp(t1, t2 PASS_REGS);
if (LOCAL_ArithError) { Yap_Error(LOCAL_Error_TYPE, LOCAL_Error_Term, LOCAL_ErrorMessage); return FALSE; }
return out;
}
static Int
p_acomp( USES_REGS1 )
{ /* $a_compare(?R,+X,+Y) */
Term t1 = Deref(ARG1);
Term t2 = Deref(ARG2);
Int out;
out = a_cmp(t1, t2 PASS_REGS);
if (LOCAL_ArithError) { Yap_Error(LOCAL_Error_TYPE, LOCAL_Error_Term, LOCAL_ErrorMessage); return FALSE; }
return out;
}
/**
@pred +_X_ =:= _Y_ is iso
Equality of arithmetic expressions
The value of the expression _X_ is equal to the value of expression _Y_.
*/
/// @memberof =:=/2
static Int
a_eq(Term t1, Term t2)
{
CACHE_REGS
/* A =:= B */
int out;
if (IsVarTerm(t1)) {
Yap_Error(INSTANTIATION_ERROR, t1, "=:=/2");
return(FALSE);
}
if (IsVarTerm(t2)) {
Yap_Error(INSTANTIATION_ERROR, t2, "=:=/2");
return(FALSE);
}
if (IsFloatTerm(t1)) {
if (IsFloatTerm(t2))
return (FloatOfTerm(t1) == FloatOfTerm(t2));
else if (IsIntegerTerm(t2)) {
return (FloatOfTerm(t1) == IntegerOfTerm(t2));
}
}
if (IsIntegerTerm(t1)) {
if (IsIntegerTerm(t2)) {
return (IntegerOfTerm(t1) == IntegerOfTerm(t2));
} else if (IsFloatTerm(t2)) {
return (FloatOfTerm(t2) == IntegerOfTerm(t1));
}
}
out = a_cmp(t1,t2 PASS_REGS);
if (LOCAL_ArithError) { Yap_Error(LOCAL_Error_TYPE, LOCAL_Error_Term, LOCAL_ErrorMessage); return FALSE; }
return out == 0;
}
/*
@pred +_X_ =\\= _Y_ is iso
Difference of arithmetic expressions
The value of the expression _X_ is different from the value of expression _Y_.
*/
/// @memberof =\\=/2
static Int
a_dif(Term t1, Term t2)
{
CACHE_REGS
Int out = a_cmp(Deref(t1),Deref(t2) PASS_REGS);
if (LOCAL_ArithError) { Yap_Error(LOCAL_Error_TYPE, LOCAL_Error_Term, LOCAL_ErrorMessage); return FALSE; }
return out != 0;
}
/**
@pred +_X_ \> +_Y_ is iso
Greater than arithmetic expressions
The value of the expression _X_ is less than or equal to the value
of expression _Y_.
*/
static Int
a_gt(Term t1, Term t2)
{ /* A > B */
CACHE_REGS
Int out = a_cmp(Deref(t1),Deref(t2) PASS_REGS);
if (LOCAL_ArithError) { Yap_Error(LOCAL_Error_TYPE, LOCAL_Error_Term, LOCAL_ErrorMessage); return FALSE; }
return out > 0;
}
/**
@pred +_X_ >= +_Y_ is iso
Greater than or equal to arithmetic expressions
The value of the expression _X_ is greater than or equal to the
value of expression _Y_.
*/
static Int
a_ge(Term t1, Term t2)
{ /* A >= B */
CACHE_REGS
Int out = a_cmp(Deref(t1),Deref(t2) PASS_REGS);
if (LOCAL_ArithError) { Yap_Error(LOCAL_Error_TYPE, LOCAL_Error_Term, LOCAL_ErrorMessage); return FALSE; }
return out >= 0;
}
/**
@pred +_X_ \< +_Y_ is iso
Lesser than arithmetic expressions
The value of the expression _X_ is less than the value of expression
_Y_.
*/
/// @memberof </2
static Int
a_lt(Term t1, Term t2)
{ /* A < B */
CACHE_REGS
Int out = a_cmp(Deref(t1),Deref(t2) PASS_REGS);
if (LOCAL_ArithError) { Yap_Error(LOCAL_Error_TYPE, LOCAL_Error_Term, LOCAL_ErrorMessage); return FALSE; }
return out < 0;
}
/**
*
@pred _X_ =< + _Y_
Lesser than or equal to arithmetic expressions
The value of the expression _X_ is less than or equal to the value
of expression _Y_.
*/
/// @memberof =</2
static Int
a_le(Term t1, Term t2)
{ /* A <= B */
CACHE_REGS
Int out = a_cmp(Deref(t1),Deref(t2) PASS_REGS);
if (LOCAL_ArithError) { Yap_Error(LOCAL_Error_TYPE, LOCAL_Error_Term, LOCAL_ErrorMessage); return FALSE; }
return out <= 0;
}
/**
@}
*/
void
Yap_InitCmpPreds(void)
{
Yap_InitCmpPred("=:=", 2, a_eq, SafePredFlag | BinaryPredFlag);
Yap_InitCmpPred("=\\=", 2, a_dif, SafePredFlag | BinaryPredFlag);
Yap_InitCmpPred(">", 2, a_gt, SafePredFlag | BinaryPredFlag);
Yap_InitCmpPred("=<", 2, a_le, SafePredFlag | BinaryPredFlag);
Yap_InitCmpPred("<", 2, a_lt, SafePredFlag | BinaryPredFlag);
Yap_InitCmpPred(">=", 2, a_ge, SafePredFlag | BinaryPredFlag);
Yap_InitCPred("$a_compare", 3, p_acomp, TestPredFlag | SafePredFlag);
Yap_InitCmpPred("\\==", 2, a_noteq, BinaryPredFlag | SafePredFlag);
Yap_InitCmpPred("@<", 2, a_gen_lt, BinaryPredFlag | SafePredFlag);
Yap_InitCmpPred("@=<", 2, a_gen_le, BinaryPredFlag | SafePredFlag);
Yap_InitCmpPred("@>", 2, a_gen_gt, BinaryPredFlag | SafePredFlag);
Yap_InitCmpPred("@>=", 2, a_gen_ge, BinaryPredFlag | SafePredFlag);
Yap_InitCPred("compare", 3, p_compare, TestPredFlag | SafePredFlag);
}
/**
@}
*/