solnic/dm-session — comment on commit 6e67474c7325d51bc989e13a4aedaeb82b33ab44
File: spec/unit/data_mapper/session/command/command_spec.rb line 19
By dkubb:

I know the code allows it, but I would think a nice api would be one that allowed any object that responds to `#call` to be passed in.