class Diff::LCS::Hunk

def ed_diff(format)
  op_act = { "+" => 'a', "-" => 'd', "!" => "c" }
  warn "Expecting only one block in an old diff hunk!" if @blocks.size > 1
  if format == :reverse_ed
    s = encode("#{op_act[@blocks[0].op]}#{context_range(:old)}\n")
  else
    s = encode("#{context_range(:old, ' ')}#{op_act[@blocks[0].op]}\n")
  end
  unless @blocks[0].insert.empty?
    @data_new[@start_new .. @end_new].each { |e| s << e + encode("\n") }
    s << encode(".\n")
  end
  s
end