class Byebug::HelpCommand

def execute
  if @match[1]
    args = @match[1].split
    cmds = @state.commands.select { |cmd| cmd.names.include?(args[0]) }
    unless cmds.empty?
      help = cmds.map{ |cmd| cmd.help(args) }.join("\n")
      help = help.split("\n").map{|l| l.gsub(/^ +/, '')}
      help.shift if help.first && help.first.empty?
      help.pop if help.last && help.last.empty?
      return print help.join("\n") + "\n"
    else
      return errmsg "Undefined command: \"#{args[0]}\". Try \"help\".\n" if
        args[0]
    end
  end
  print "byebug help v#{Byebug::VERSION}\n" unless Setting[:testing]
  print "Type \"help <command-name>\" for help on a specific command\n\n"
  print "Available commands:\n"
  cmds = @state.commands.map{ |cmd| cmd.names }.flatten.uniq.sort
  print columnize(cmds, Setting[:width])
end