This repository has been archived on 2023-08-20.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.
vsc e5f4633c39 This commit was generated by cvs2svn to compensate for changes in r4,
which included commits to RCS files with non-trunk default branches.


git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@5 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
2001-04-09 19:54:03 +00:00

146 lines
3.3 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: eval.c *
* Last rev: *
* mods: *
* comments: arithmetical expression evaluation *
* *
*************************************************************************/
#ifdef SCCS
static char SccsId[] = "%W% %G%";
#endif
/*
* This file implements arithmetic operations
*
*/
#include "Yap.h"
#include "Yatom.h"
#include "Heap.h"
#include "eval.h"
yap_error_number YAP_matherror = NO_ERROR;
#define E_FUNC blob_type
#define E_ARGS arith_retptr o
#define USE_E_ARGS o
#define RBIG(v) (o)->big = v; return(big_int_e)
#define RINT(v) (o)->Int = v; return(long_int_e)
#define RFLOAT(v) (o)->dbl = v; return(double_e)
#define RERROR() return(db_ref_e)
static Term
EvalToTerm(blob_type bt, union arith_ret *res)
{
switch (bt) {
case long_int_e:
return(MkIntegerTerm(res->Int));
case double_e:
return(MkFloatTerm(res->dbl));
#ifdef USE_GMP
case big_int_e:
return(MkBigIntTerm(res->big));
#endif
default:
return(TermNil);
}
}
E_FUNC
Eval(Term t, E_ARGS)
{
if (IsVarTerm(t)) {
Error(INSTANTIATION_ERROR,TermNil,"in arithmetic");
P = (yamop *)FAILCODE;
RERROR();
}
if (IsApplTerm(t)) {
Functor fun = FunctorOfTerm(t);
switch ((CELL)fun) {
case (CELL)FunctorLongInt:
RINT(LongIntOfTerm(t));
case (CELL)FunctorDouble:
RFLOAT(FloatOfTerm(t));
#ifdef USE_GMP
case (CELL)FunctorBigInt:
RBIG(BigIntOfTerm(t));
#endif
default:
{
Int n = ArityOfFunctor(fun);
Atom name = NameOfFunctor(fun);
ExpEntry *p;
if (EndOfPAEntr(p = RepExpProp(GetExpProp(name, n)))) {
Term ti[2];
/* error */
ti[0] = t;
ti[1] = MkIntegerTerm(n);
t = MkApplTerm(MkFunctor(LookupAtom("/"),2), 2, ti);
Error(TYPE_ERROR_EVALUABLE, t,
"functor %s/%d for arithmetic expression",
RepAtom(name)->StrOfAE,n);
P = (yamop *)FAILCODE;
RERROR();
}
if (n == 1)
return(p->FOfEE.unary(ArgOfTerm(1,t), USE_E_ARGS));
return(p->FOfEE.binary(ArgOfTerm(1,t),ArgOfTerm(2,t), USE_E_ARGS));
}
}
} else if (IsPairTerm(t)) {
return(Eval(HeadOfTerm(t), USE_E_ARGS));
} else if (IsIntTerm(t)) {
RINT(IntOfTerm(t));
} else {
Atom name = AtomOfTerm(t);
ExpEntry *p;
if (EndOfPAEntr(p = RepExpProp(GetExpProp(name, 0)))) {
Term ti[2];
/* error */
ti[0] = t;
ti[1] = MkIntTerm(0);
t = MkApplTerm(MkFunctor(LookupAtom("/"),2), 2, ti);
Error(TYPE_ERROR_EVALUABLE, t,
"functor %s/%d for arithmetic expression",
RepAtom(name)->StrOfAE,0);
P = (yamop *)FAILCODE;
RERROR();
}
return(p->FOfEE.constant(USE_E_ARGS));
}
}
static Int
p_is(void)
{ /* X is Y */
union arith_ret res;
blob_type bt;
bt = Eval(Deref(ARG2), &res);
return (unify_constant(ARG1,EvalToTerm(bt,&res)));
}
void
InitEval(void)
{
/* here are the arithmetical predicates */
InitConstExps();
InitUnaryExps();
InitBinaryExps();
InitCPred("is", 2, p_is, TestPredFlag | SafePredFlag);
}