{"author_url":"https://blog.hatena.ne.jp/osyo-manga/","image_url":null,"blog_url":"https://secret-garden.hatenablog.com/","categories":["Ruby"],"provider_url":"https://hatena.blog","type":"rich","version":"1.0","description":"\u6b21\u306e\u3088\u3046\u306b #eval \u30e1\u30bd\u30c3\u30c9\u3067\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u3092\u5b9a\u7fa9\u3057\u305f\u5834\u5408\u3001\u5916\u304b\u3089\u306f\u53c2\u7167\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u306a\u3044\u3002 eval \"a = 42\" p a + a # => error: undefined local variable or method `a' for main:Object (NameError) \u3053\u308c\u306f expr \u5185\u306e\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u306e\u6271\u3044\u304c\u30d6\u30ed\u30c3\u30af\u3068\u540c\u3058\u70ba\u3001\u5916\u304b\u3089\u53c2\u7167\u3059\u308b\u4e8b\u304c\u3067\u304d\u306a\u3044\u304b\u3089\u3067\u3059\u3002 \u9006\u306b\u3044\u3048\u3070\u3001\u3059\u3067\u306b\u5ba3\u8a00\u3055\u308c\u3066\u3044\u308b\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u306b\u5bfe\u3057\u3066\u306e\u4ee3\u5165\u3084 expr \u5185\u3067\u306e\u53c2\u7167\u306f\u884c\u3046\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002 x = 0 # \u3059\u3067\u306b\u5ba3\u8a00\u3055\u308c\u3066\u3044\u308b\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u306b\u4ee3\u5165\u3059\u308b\u3053\u3068\u306f\u3067\u304d\u308b eval \"a = 42;\u2026","title":"Ruby \u306e eval \u30e1\u30bd\u30c3\u30c9\u3067\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u5b9a\u7fa9\u306f\u3067\u304d\u306a\u3044","url":"https://secret-garden.hatenablog.com/entry/2015/09/07/000000","width":"100%","height":"190","author_name":"osyo-manga","provider_name":"Hatena Blog","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fsecret-garden.hatenablog.com%2Fentry%2F2015%2F09%2F07%2F000000\" title=\"Ruby \u306e eval \u30e1\u30bd\u30c3\u30c9\u3067\u30ed\u30fc\u30ab\u30eb\u5909\u6570\u5b9a\u7fa9\u306f\u3067\u304d\u306a\u3044 - Secret Garden(Instrumental)\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","blog_title":"Secret Garden(Instrumental)","published":"2015-09-06 00:00:00"}