{"title":"arrow function\u3067\u30cf\u30de\u308b","categories":["JavaScript","\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0"],"height":"190","version":"1.0","provider_url":"https://hatena.blog","published":"2016-02-17 15:22:23","blog_url":"https://mactkg.hateblo.jp/","author_name":"mactkg","blog_title":"\u534a\u7a7a\u6d1e\u7537\u5973\u95a2\u4fc2","description":"function O () { this.value = 200 // Type A this.f = () => { console.log(this.value) } } // Type B O.prototype.g = () => { console.log(this.value) } var obj = new O() obj.f() //=> 200 obj.g() //=> undefined \u4eca\u307e\u3067\u305a\u3063\u3068TypeB\u306e\u30b9\u30bf\u30a4\u30eb\u3067\u30af\u30e9\u30b9\u3092\u8868\u73fe\u3057\u3066\u3044\u305f\u3051\u3069(arrow function\u3067\u306f\u306a\u3044)\uff0carrow function\u306b\u5909\u3048\u305f\u3089\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306e\u5024\u306b\u30a2\u30af\u30bb\u30b9\u3067\u304d\u306a\u304f\u3066\u30cf\u30de\u3063\u305f\uff0e \u30a2\u2026","width":"100%","author_url":"https://blog.hatena.ne.jp/mactkg/","url":"https://mactkg.hateblo.jp/entry/2016/02/17/152223","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fmactkg.hateblo.jp%2Fentry%2F2016%2F02%2F17%2F152223\" title=\"arrow function\u3067\u30cf\u30de\u308b - \u534a\u7a7a\u6d1e\u7537\u5973\u95a2\u4fc2\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","type":"rich","image_url":null,"provider_name":"Hatena Blog"}