all (DataMapper::Collection)

    # File lib/dm-core/collection.rb, line 177
        def all(query = nil)
          if query.nil? || (query.kind_of?(Hash) && query.empty?)
            dup
          else
            # TODO: if there is no order parameter, and the Collection is not loaded
            # check to see if the query can be satisfied by the head/tail

            new_collection(scoped_query(query))
          end
        end