>>> For example a < b is re-written as a.opCmp(b) < 0. >>> In my application, I wanted to overload comparison and equality >>> operators to return user defined values. Is that possible in D? If so >>> how? >> >> What are you trying to do? >> In the end opCmp can return any value or object that works in the >> rewritten case 'a.opCmp(b) < 0'. > > Which is a fancy way of returning an int. Probably he wants to implement > expression templates. >
Actually not expression templates. I am porting a BDD (Binary decision diagrams) library from C++ to D. The comparison operators are just implemented as relations that return another BDD. A BDD would then evaluate to 0 or 1 depending on many other factors and other BDDs. A BDD actually represents a node on an acyclic graph. Being able to overload comparison operators more generically would have helped. For now I am using named functions as Timon suggested. Regards - Puneet
