static ord_RESULT rpos_MulGreaterEqual(TERM T1, TERM T2)
/**************************************************************
INPUT: Two terms with equal top symbols and multiset status.
RETURNS: ord_GREATER_THAN if <T1> is greater than <T2>,
ord_EQUAL if both terms are equal and
ord_UNCOMPARABLE otherwise.
***************************************************************/
{
LIST l1, l2;
l1 = rpos_MultisetDifference(T1, T2);
if (list_Empty(l1))
/* If |M| = |N| and M-N = {} then N-M = {} */
return ord_Equal(); /* Terms are equal */
else {
LIST scan;
BOOL greater;
l2 = rpos_MultisetDifference(T2, T1);
for (greater = TRUE; !list_Empty(l2) && greater; l2 = list_Pop(l2)) {
for (scan = l1, greater = FALSE; !list_Empty(scan) && !greater; scan = list_Cdr(scan))
greater = rpos_Greater(list_Car(scan), list_Car(l2));
}
list_Delete(l1); /* l2 was freed in the outer for loop */
if (greater)
return ord_GreaterThan();
else
return ord_Uncomparable();
}
}
static ord_RESULT rpos_MulGreaterEqual(TERM T1, TERM T2, BOOL VarIsConst)
/**************************************************************
INPUT: Two terms with equal top symbols and multiset status.
RETURNS: ord_GREATER_THAN if <T1> is greater than <T2>,
ord_EQUAL if both terms are equal and
ord_UNCOMPARABLE otherwise.
CAUTION: If <VarIsConst> is set then variables are interpreted as constants
with lowest precedence. They are ranked to each other using
their variable index.
***************************************************************/
{
LIST l1, l2;
l1 = rpos_MultisetDifference(T1, T2);
if (list_Empty(l1))
/* If |M| = |N| and M-N = {} then N-M = {} */
return ord_Equal(); /* Terms are equal */
else {
LIST scan;
BOOL greater;
l2 = rpos_MultisetDifference(T2, T1);
for (greater = TRUE; !list_Empty(l2) && greater; l2 = list_Pop(l2)) {
for (scan = l1, greater = FALSE; !list_Empty(scan) && !greater; scan = list_Cdr(scan))
greater = rpos_Greater(list_Car(scan), list_Car(l2), VarIsConst);
}
list_Delete(l1); /* l2 was freed in the outer for loop */
if (greater)
return ord_GreaterThan();
else
return ord_Uncomparable();
}
}
BOOL rpos_Equal(TERM T1, TERM T2)
/**************************************************************
INPUT: Two terms.
RETURNS: TRUE, if <T1> is equal to <T2> and
FALSE otherwise.
***************************************************************/
{
LIST l1, l2;
if (!term_EqualTopSymbols(T1, T2))
return FALSE;
else if (!term_IsComplex(T1)) /* Equal variable or constant */
return TRUE;
else {
if (symbol_HasProperty(term_TopSymbol(T1), ORDMUL)) { /* MUL case */
l1 = rpos_MultisetDifference(T1, T2);
if (list_Empty(l1))
return TRUE;
else {
list_Delete(l1);
return FALSE;
}
} else { /* LEX case */
for (l1 = term_ArgumentList(T1), l2 = term_ArgumentList(T2);
!list_Empty(l1) && rpos_Equal(list_Car(l1), list_Car(l2));
l1 = list_Cdr(l1), l2 = list_Cdr(l2))
/* empty */;
return list_Empty(l1); /* All arguments were equal */
}
}
}
