@Override
public boolean unify(Term t1) {
// used to be implemented using recursion but caused stack overflow problems with long lists
Term t2 = this;
do {
TermType tType = t1.getType();
if (tType == TermType.LIST) {
if (t2.getArgument(0).unify(t1.getArgument(0)) == false) {
return false;
}
t1 = t1.getArgument(1);
t2 = t2.getArgument(1);
} else if (tType.isVariable()) {
return t1.unify(t2);
} else {
return false;
}
} while (t2.getType() == TermType.LIST);
return t2.unify(t1);
}
