> To make things more clear, the current implementation of Behavior >> #hash > has two negative side effects: > - behaviors stored in collections relying on the hash value (e.g. Set, > Dictionary) will have to be rehashed whenever a behavior is renamed > - objects using Behavior >> #hash to implement their own #hash, like what > Eliot just did to Message will suffer from the same issue. So Sets and > Dictionaries holding those kind of objects will have to be rehashed as > well upon the rename of the behavior. > > My questions related to this: > - why does Behavior >> #hash rely on the name instead of identity? If you mean #identityHash, then its because involving an unstable value in a #hash calculation is never a good idea. #identityHash can be different for the same class between two different images, or if the class was ever becomed or reloaded into a new image, etc. > - do we want to fix those issues mentioned above or do we just say that > one should not rename classes and expect things to work? Neither. We just say that when one renames a class to rehash all relevant HashedCollections. - Chris