[]= (Thor::OrderedHash)

    # File lib/thor/ordered_hash.rb, line 21
        def []=(key, value)
          node = Node.new(key, value)

          if old = @hash[key]
            if old.prev
              old.prev.next = old.next
            else # old is @first and @last
              @first = @last = nil
            end
          end

          if @first.nil?
            @first = @last = node
          else
            node.prev = @last
            @last.next = node
            @last = node
          end

          @hash[key] = node
          value
        end