This is what I settled on -- at least in the hard cases. And if I understand his acronyms, it's also what @mythz is recommending. Perhaps I should have done i

This is what I settled on -- at least in the hard cases. And if I understand his acronyms, it's also what @mythz is recommending. Perhaps I should have done it for the easy cases as well (where the business objects are struct-like enough that it doesn't matter) and just lived with the boilerplate. But I see little advantage in this over just having a dictionary that I can inspect to initialise my real business object. True that is not strongly-typed, but the stage between the message-object and the business object can have validation errors anyway, so why not treat typechecking as part of that?