Extension to silently ignore undeclared properties at init

I'm using Trashes as very simple data mappers for data I consume from RESTful services. The problem is that these services return much more data in the JSON than I really need, so I can't directly populate my Trashes from these raw JSON-turned-hashes.

So I built this extension to silently ignore extra (undeclared) attributes provided at initialization.

I'm not in love with the extension name, but I couldn't think of anything better. Any ideas on a better name?