# File lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 1074
  def self.binary_search(ary, value, &block)
    upper = ary.size - 1
    lower = 0
    idx = 0

    while(lower <= upper) do
      idx = (lower + upper) / 2
      comp = ary[idx].value <=> value

      if comp == 0
        return idx
      elsif comp > 0
        upper = idx - 1
      else
        lower = idx + 1
      end
    end
    return upper
  end