public Assign Assign(Tree lhs, Tree rhs) { return Assign(lhs.pos, lhs, rhs);
public Assign Assign(int pos, Tree lhs, Tree rhs) { Assign tree = make.Assign(pos, lhs, rhs); global.nextPhase(); tree.setType(definitions.void_TYPE()); global.prevPhase(); return tree;
    public Assign Assign(Tree lhs, Tree rhs) {        return Assign(lhs.pos, lhs, rhs);    }