Pretty easy to do `type MyGc<T> = Gc<RefCell<T>>`.
Even better, put trait objects everywhere. Now we're Java. Go sit in a corner and think about what you've done :P
When designing rust-gc with mystor at one point I joked about writing a syntax extension that converts everything in a crate to a GCd, RefCelld, trait object, so that Java programmers have no problem converting.
