ord_RESULT rpos_ContCompare(CONTEXT C1, TERM T1, CONTEXT C2, TERM T2)
/**************************************************************
INPUT: Two contexts and two terms.
RETURNS: The relation between the two terms with respect to the
RPOS ordering:
ord_GREATER_THAN if <T1> is greater than <T2>,
ord_EQUAL if both terms are equal,
ord_SMALLER_THAN if <T2> is greater than <T1> and
ord_UNCOMPARABLE otherwise.
EFFECT: Variable bindings are considered.
CAUTION: The precedence from the order module is used to determine
the precedence of symbols!
***************************************************************/
{
ord_RESULT result;
T1 = cont_Deref(&C1, T1);
T2 = cont_Deref(&C2, T2);
result = rpos_ContGreaterEqual(C1, T1, C2, T2);
if (!ord_IsUncomparable(result))
return result;
else if (rpos_ContGreater(C2, T2, C1, T1))
return ord_SmallerThan();
else
return ord_UNCOMPARABLE;
}
ord_RESULT rpos_ContCompareAux(CONTEXT C1, TERM T1, CONTEXT C2, TERM T2, BOOL VarIsConst)
/**************************************************************
INPUT: Two contexts and two terms.
RETURNS: The relation between the two terms with respect to the
RPOS ordering:
ord_GREATER_THAN if <T1> is greater than <T2>,
ord_EQUAL if both terms are equal,
ord_SMALLER_THAN if <T2> is greater than <T1> and
ord_UNCOMPARABLE otherwise.
EFFECT: Variable bindings are considered.
If VarIsConst is true variables are interpreted as constants
CAUTION: The precedence from the order module is used to determine
the precedence of symbols!
If <VarIsConst> is set then variables are interpreted as constants
with lowest precedence. They are ranked to each other using
their variable index.
***************************************************************/
{
ord_RESULT result;
CONTEXT GlobalC1, GlobalC2;
GlobalC1 = C1;
GlobalC2 = C2;
T1 = cont_Deref(GlobalC1, &C1, T1);
T2 = cont_Deref(GlobalC2, &C2, T2);
result = rpos_ContGreaterEqual(GlobalC1, C1, T1, GlobalC2, C2, T2, VarIsConst);
if (!ord_IsUncomparable(result))
return result;
else if (rpos_ContGreaterAux(GlobalC2, C2, T2, GlobalC1, C1, T1, VarIsConst))
return ord_SmallerThan();
else
return ord_UNCOMPARABLE;
}
ord_RESULT rpos_CompareAux(TERM T1, TERM T2, BOOL VarIsConst)
/**************************************************************
INPUT: Two terms, a boolean flag indicating if variables
of <T1> and <T2> are interpreted as skolem constants
RETURNS: The relation between the two terms with respect to the
RPOS ordering:
ord_GREATER_THAN if <T1> is greater than <T2>,
ord_EQUAL if both terms are equal,
ord_SMALLER_THAN if <T2> is greater than <T1> and
ord_UNCOMPARABLE otherwise.
CAUTION: The precedence from the order module is used to determine
the precedence of symbols!
If <VarIsConst> is set then variables are interpreted as constants
with lowest precedence. They are ranked to each other using
their variable index.
***************************************************************/
{
ord_RESULT result;
result = rpos_GreaterEqual(T1, T2, VarIsConst);
if (!ord_IsUncomparable(result))
return result;
else if (rpos_Greater(T2, T1, VarIsConst))
return ord_SmallerThan();
else
return ord_UNCOMPARABLE;
}
ord_RESULT rpos_Compare(TERM T1, TERM T2)
/**************************************************************
INPUT: Two terms.
RETURNS: The relation between the two terms with respect to the
RPOS ordering:
ord_GREATER_THAN if <T1> is greater than <T2>,
ord_EQUAL if both terms are equal,
ord_SMALLER_THAN if <T2> is greater than <T1> and
ord_UNCOMPARABLE otherwise.
CAUTION: The precedence from the order module is used to determine
the precedence of symbols!
***************************************************************/
{
ord_RESULT result;
result = rpos_GreaterEqual(T1, T2);
if (!ord_IsUncomparable(result))
return result;
else if (rpos_Greater(T2, T1))
return ord_SmallerThan();
else
return ord_UNCOMPARABLE;
}