HasOperatorOverloading

A map of operator codes and function names acting as overloaded operators. The key is a pair of the class and HasOperatorCode.operatorCode (ideally created by of) and the value is the name of the function.

Returns the matching operator code for name in overloadedOperatorNames. While overloadedOperatorNames can have multiple entries for a single operator code (e.g. to differentiate between unary and binary ops), we only ever allow one distinct operator code for a specific symbol. If non such distinct operator code is found, null is returned.