Thor example

app.rb

# encoding: utf-8
require 'thor'

class App < Thor
  desc 'hello', "Let's say hello!"
  def hello
    puts 'Hello world!'
  end

  desc 'konichiwa NAME', 'say hello to NAME san in Japanese'
  def konichiwa name
    puts "こんにちは、#{name} さん!"
  end

  desc 'greet [NAME]', 'greet to people'
  method_option :japanese,
    :type    => :boolean,
    :aliases => '-j',
    :desc    => 'in Japanese'
  def greet name = 'world'
    if options[:japanese]
      konichiwa name
    else
      puts "Hello #{name}"
    end
  end

end

App.start