@Override
public Expression<?> duplicate(Expression<?>[] newChildren) {
assert newChildren.length == 1;
if (negated == newChildren[0]) return this;
return UnaryMinus.create(newChildren[0]);
}
@Override
public <E> String visit(UnaryMinus<E> n, HashMap<Class, String> data) {
String negated = visit(n.getNegated());
return TransitionEncoding.unaryMinus + ":" + negated + ";";
}