    # File lib/termtter/command.rb, line 44
        def complement(input)
          input = input.sub(/^\s*/, '')
          if match?(input) && input =~ /^[^\s]+\s/
            if completion_proc
              command_str, command_arg = split_command_line(input)
              [completion_proc.call(command_str, command_arg || '')].flatten.compact
            else
              []
            end
          else
            []
          end
        end