Route 477

■ [ruby] Common Lisp的な、「再開可能な例外」をRubyで

実装は以下。もちろん継続ですｗ

• Magnus Holm - Continue that exception

例：

10.times do |i|
  begin
    raise "OH NO!"
    puts "OH YES! #{i}"
    i += 1
  rescue => err
    if i < 5
      err.continue  ### これ(Exception#continue)が「例外が発生した次の行」に飛ぶ
    else
      raise err
    end
  end
end

実行結果：

/tmp % ruby-1.9 -rcontinuation a.rb
OH YES! 0
OH YES! 1
OH YES! 2
OH YES! 3
OH YES! 4
a.rb:48:in `rescue in block in <main>': RuntimeError (RuntimeError)
        from a.rb:40:in `block in <main>'
        from a.rb:39:in `times'
        from a.rb:39:in `<main>'