#4 API for callback-method return values

[Henrik Kaipe]

Today all callback-invocations will return default-values (i.e. false, 0, null etc depending on return-type), in case they are non-void. Therewith the callback-method return-values constitute an unused piece of API that should be taken care of so. The question is how? Does anyone have any good ideas on what an API for callback-method return-values should look like?
This can be seen as an opportunity to develop some really useful and innovative features, so let us not settle for anything less than really fency features, which benefits cannot be easily reproduced with any existing tools out there. :-)