YokoKen https://blog.hatena.ne.jp/YokoKen/ 気楽に諸々 https://yokoken.hatenadiary.org/ Ruby ほへ〜、オブジェクトのインスタンス変数の変更を禁止できるとは class Hoge def initialize @var = "" end attr_accessor :var end h = Hoge.new() h.var = "abc" h.freeze() begin h.var = "aiueo" rescue TypeError => err puts err.message #=> can't modify frozen object end 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fyokoken.hatenadiary.org%2Fentry%2F20090211%2F1234359307" title="freeze メソッド - 気楽に諸々" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> Hatena Blog https://hatena.blog 2009-02-11 22:35:07 rich https://yokoken.hatenadiary.org/entry/20090211/1234359307 1.0 100%