class C
    include Enumerable
    ...
    def each(&proc)
        @myarray.each do |e|
            proc.call(e)
        end
    end
end

Nebo lépe

def each(&block)
    @myarray.each(&+block)
end

S použitím modulu Forwardable pak

require 'forwardable'

class C
    extend Forwardable
    def_delegators(:@myarray, :each)
end