def grep(pattern, &block) # :nodoc: #
      greped = super(pattern, &block)
      block_given? ? greped : extend_result(greped)
    end
def grep(pattern, &block) # :nodoc: #
      greped = super(pattern, &block)
      block_given? ? greped : extend_result(greped)
    end
See Enumerable.grep