public override bool Unify (BaseTerm t, VarStack varStack)
{
if ((t = t.ChainEnd ()) is Variable) // t not unified
{
((Variable)t).Bind (this);
varStack.Push (t);
return true;
}
if (t is ListPatternTerm && arity == t.Arity) // two ListPatternTerms match if their rangeTerms match
{
for (int i = 0; i < arity; i++)
if (!args [i].Unify (t.Args [i], varStack)) return false;
return true;
}
if (t is ListTerm)
{
pattern = args; // pattern is searched ...
target = ((ListTerm)t).ToList (); // ... in target
int ip = 0;
int it = 0;
return UnifyTailEx (ip, it, varStack);
}
return false;
}
public bool Unify(Term t, VarStack varStack, bool occurCheck)
{
if (isUnified) return ULink.Unify(t, varStack, occurCheck);
if (t.isUnified) return Unify(t.ULink, varStack, occurCheck);
//Interpreter.UCount++;
if (hasValue)
{
if (t.hasValue)
{
if (_functor.Equals(t._functor) && arity == t.Arity) // => two cuts will unify as well
{
for (int i = 0; i < arity; i++) if (!args[i].Unify(t.Arg(i), varStack, occurCheck)) return false;
return true;
}
else
return false;
}
// t is an unbound variable (add occur check here if deemed necessary)
t.Bind(this);
varStack.Push(t);
}
else // 'this' is an unbound variable. Add occur check here if deemed necessary
{
this.Bind(t);
varStack.Push(this);
}
return true;
}