public Boolean apply(String property, Object value) {
Pair<Variable, String> key = Pair.make(reference.first, reference.second + "#" + property);
externalValueMap.put(key, value);
public Boolean apply(String property, Object value) {
Pair<Variable, String> key = Pair.make(reference.first, reference.second + "#" + property);
externalValueMap.put(key, value);