// Let all UNION-Variable through, but not the ones which the new
// ReplaceVar has replaced (right side)
final LinkedList<Variable> projVars = new LinkedList<Variable>();
for (int i = 0; i < unionVars.length; i++) {
final Variable var = (Variable) unionVars[i];
if (!replaceVarsRight.contains(var)) {
projVars.add(var);
}
}