Have a look at this class:

  http://github.com/proutils/lemon/blob/master/lib/lemon/snapshot.rb

I am storing a collection of OfModule instances in a hash (@modules)
indexed by the modules they correspond to. I'd rather just use an
array, since that is the basic intent. But I ran into difficulty when
implementing the #- method, which led me to use the hash instead.

Is there an efficient way to implement the #- method if @modules were
an array instead of a hash?

Feel free to offer any other critiques of this code too, btw.

                                 trans.