private bool IsPredicate(PrologObject fact, StringObject atom)
{
if (fact.Equals(atom))
{
return(true);
}
if (!(fact is StructureObject))
{
return(false);
}
StructureObject st = ((StructureObject)(fact));
if (st.Functor.Equals(atom))
{
return(true);
}
if (!(st.Functor == IfPrimitive.GetInstance()))
{
return(false);
}
fact = st.Parameters[0];
if (fact.Equals(atom))
{
return(true);
}
if (!(fact is StructureObject))
{
return(false);
}
st = (StructureObject)fact;
if (st.Functor.Equals(atom))
{
return(true);
}
return(false);
}
public bool Unify(PrologObject po1, PrologObject po2)
{
po1 = po1.Dereference();
po2 = po2.Dereference();
if (po1.Equals(po2))
{
return(true);
}
if (po1 is Variable)
{
((Variable)(po1)).Bind(po2);
return(true);
}
if (po2 is Variable)
{
((Variable)(po2)).Bind(po1);
return(true);
}
if (po1 is StructureObject && po2 is StructureObject)
{
StructureObject st1 = ((StructureObject)(po1));
StructureObject st2 = ((StructureObject)(po2));
if (!(Unify(st1.Functor, st2.Functor)))
{
return(false);
}
if (!(st1.Arity == st2.Arity))
{
return(false);
}
for (int k = 0; k <= st1.Arity - 1; k++)
{
if (!(Unify(st1.Parameters[k], st2.Parameters[k])))
{
return(false);
}
}
return(true);
}
return(false);
}