Weave together multiple sorted enumerables into one sorted enumerable. (The supplied block is what to sort by, and an enumerable is returned.)

enum_weave.rb

def weave(*enums, &key_getter)
  enums = enums.map { |e| e.to_enum.each }

  Enumerator.new do |yielder|
    while enums.any?

      enums.sort_by! { |enum| key_getter.call(enum.peek) rescue 0 }

      begin
        yielder << enums.first.next
      rescue StopIteration
        enums.shift
      end

    end
  end
end


lesspipe do |less|
  weave(URLActivity, APIActivity) { |rec| -rec[:time] }.each do |a|
    a.print(less)
  end
end