# File lib/backports/1.8.7/enumerable.rb, line 148
  def minmax
    return minmax{|a,b| a <=> b} unless block_given?
    first_time = true
    min, max = nil
    each do |object|
      if first_time
        min = max = object
        first_time = false
      else
        min = object if Backports.coerce_to_comparison(min, object, yield(min, object)) > 0
        max = object if Backports.coerce_to_comparison(max, object, yield(max, object)) < 0
      end
    end
    [min, max]
  end