{"id":14342,"date":"2019-06-17T09:00:31","date_gmt":"2019-06-17T00:00:31","guid":{"rendered":"https:\/\/www.agent-grow.com\/self20percent\/?p=14342"},"modified":"2019-06-11T08:55:26","modified_gmt":"2019-06-10T23:55:26","slug":"why-use-let-or-const-in-js-code","status":"publish","type":"post","link":"https:\/\/www.agent-grow.com\/self20percent\/2019\/06\/17\/why-use-let-or-const-in-js-code\/","title":{"rendered":"JavaScript \u3067\u306e\u5909\u6570\u5b9a\u7fa9\u306f var \u3092\u6368\u3066\u3066 let, const \u3092\u4f7f\u3046\u3079\u304d\u7406\u7531"},"content":{"rendered":"

JS \u306e\u5909\u6570\u5b9a\u7fa9\u3067\u306f let, const \u3092\u4f7f\u3046\u3079\u3057\uff01\u2026\u3063\u3066\u4f55\u3067\uff1f<\/h1>\n

JavaScript \u306f\u6700\u8fd1\u8272\u3005\u3068\u9032\u5316\u3057\u3066\u304d\u3066\u3044\u307e\u3059\u3088\u306d\u3002<\/p>\n

\u3067\u3001\u6700\u8fd1\u306e JS \u306e\u66f8\u304d\u65b9\u3068\u3057\u3066\u3088\u304f\u8a00\u308f\u308c\u3066\u3044\u308b\u306e\u306f\u3001
\n\u300c\u5909\u6570\u5b9a\u7fa9\u3067\u306f var \u3067\u306f\u306a\u304f\u3066 let, const \u3092\u4f7f\u3046\u3088\u3046\u306b\u3057\u308d\uff01\u300d
\n\u3063\u3066\u3084\u3064\u3067\u3059\u306d\u3002
\n\uff08\u3042\u308c\uff1f\u805e\u3044\u305f\u3053\u3068\u306a\u3044\u3067\u3059\u304b\uff1f\u3067\u306f\u3001\u4eca\u899a\u3048\u3066\u304f\u3060\u3055\u3044\u3002\uff09<\/p>\n

let, const \u306e\u65b9\u304c\u65b0\u3057\u3044\u66f8\u304d\u65b9\u306a\u306e\u3067\u3001\u305d\u3063\u3061\u3092\u4f7f\u3046\u3088\u3046\u306b\u3057\u3088\u3046\u2026\u304f\u3089\u3044\u306a\u611f\u3058\u3067\u3082\u3044\u3044\u306e\u3067\u3059\u304c\u3001
\n\u305b\u3063\u304b\u304f\u306a\u306e\u3067\u3001var \u3068 let, const \u304c\u3069\u306e\u3088\u3046\u306b\u9055\u3046\u306e\u304b\u3092\u8abf\u3079\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n

\u3061\u306a\u307f\u306b\u3001\u4ee5\u4e0b\u3067\u306f var \u3068 let \u3092\u6bd4\u8f03\u3057\u3066\u898b\u3066\u3044\u304d\u307e\u3059\u3002
\nlet \u3068 const \u306f\u3001\u4e00\u5ea6\u5b9a\u7fa9\u3057\u305f\u5f8c\u306b\u518d\u5ea6\u4ee3\u5165\u304c\u3067\u304d\u308b\u304b\u3069\u3046\u304b\u306e\u9055\u3044\u304f\u3089\u3044\u306a\u306e\u3067\u3001
\n\u4ee5\u4e0b\u3067\u306f let \u306e\u6027\u8cea = const \u306e\u6027\u8cea\u3068\u601d\u3063\u3066\u8aad\u3093\u3067\u304f\u3060\u3055\u3044\u3002<\/p>\n

var \u3068 let \u306e\u9055\u3044<\/h1>\n

\u518d\u5b9a\u7fa9\u304c\u3067\u304d\u308b\u304b\u3069\u3046\u304b<\/h2>\n

\u4e00\u3064\u76ee\u3067\u3059\u304c\u3001\u3053\u308c\u304c\u6700\u3082\u91cd\u8981\u306a\u9055\u3044\u3067\u3059\u3002<\/p>\n

\u3053\u3093\u306a\u611f\u3058\u3067\u2026<\/p>\n

\nvar var_value = \u2019var\u2019\nlet let_value = \u2019let\u2019;\n\n\/\/ \u518d\u5b9a\u7fa9\uff01\nvar var_value = \u2019var\u2019\nlet let_value = \u2019let\u2019;\n<\/pre>\n
\u4e00\u5ea6\u5b9a\u7fa9\u3057\u305f\u5909\u6570\u3092\u3001\u518d\u5ea6 var, let \u3067\u5b9a\u7fa9\u3059\u308b\u3068<\/p>\n
\nSyntaxError: Identifier \u2019let_value\u2019 has already been declared\n<\/pre>\n
var \u306e\u65b9\u306f\u4f55\u306e\u30a8\u30e9\u30fc\u3082\u7121\u304f\u3001\u65b0\u3057\u3044\u5024\u304c\u4ee3\u5165\u3055\u308c\u307e\u3059\u304c\u3001
\nlet \u3067\u306f\u518d\u5ea6\u5b9a\u7fa9\u3057\u305f\u6642\u70b9\u3067\u6012\u3089\u308c\u307e\u3059\u3002<\/p>\n
let \u3067\u306f\u3001\u3042\u308b\u5909\u6570\u540d\u3092\u4e0a\u306e\u65b9\u3067\u4f7f\u3063\u3066\u3044\u308b\u3053\u3068\u3092\u5fd8\u308c\u3066\u3001
\n\u9593\u9055\u3063\u3066\u518d\u5ea6\u5b9a\u7fa9\u3059\u308b\u30df\u30b9\u3092\u8d77\u3053\u3055\u306a\u3044\u3088\u3046\u306b\u3001\u3053\u306e\u3088\u3046\u306a\u4ed5\u69d8\u306b\u306a\u3063\u3066\u3044\u308b\u306e\u3067\u3059\u306d\u3002<\/p>\n
\u3061\u306a\u307f\u306b\u3001\u5f53\u7136\u3067\u3059\u304c\u3001\u5b9a\u7fa9\u3067\u306a\u304f\u3066\u518d\u4ee3\u5165\u3067\u3042\u308c\u3070\u554f\u984c\u7121\u304f\u3067\u304d\u307e\u3059\u3002
\n(const \u306f\u518d\u4ee3\u5165\u3067\u304d\u306a\u3044\u3088\u3046\u306b\u3059\u308b\u5ba3\u8a00\u306a\u306e\u3067\u3001const \u3067\u306f\u3067\u304d\u307e\u305b\u3093)<\/p>\n
\nvar var_value = \u2019var\u2019\nlet let_value = \u2019let\u2019;\n\n\/\/ \u518d\u4ee3\u5165\nvar_value = \u2019var\u2019\nlet_value = \u2019let\u2019;\n<\/pre>\n
\u30b9\u30b3\u30fc\u30d7\u306e\u9055\u3044<\/h2>\n
\u4e8c\u3064\u76ee\u306f\u30b9\u30b3\u30fc\u30d7\u306e\u9055\u3044\u3002
\n\u30b9\u30b3\u30fc\u30d7\u3068\u306f\u300c\u5909\u6570\u304c\u898b\u3048\u308b\u7bc4\u56f2\u300d\u306e\u3053\u3068\u3067\u3059\u306d\u3002<\/p>\n
\u3053\u308c\u306f\u6df1\u304f\u8003\u3048\u305a\u306b\u3001\u3068\u308a\u3042\u3048\u305a\u30b5\u30f3\u30d7\u30eb\u3092\u898b\u305f\u65b9\u304c\u3044\u3044\u3067\u3057\u3087\u3046\u3002<\/p>\n
\n(function () {\n\n  {\n    var var_value = \u2019var\u2019;\n    let let_value = \u2019let\u2019;\n    const const_value = \u2019const\u2019;\n\n    console.log(\u2019-----\u30d6\u30ed\u30c3\u30af\u5185-----\u2019);\n    console.log(\u2019\u30d6\u30ed\u30c3\u30af\u5185\u306e var \u306e\u578b = \u2019 + typeof var_value);\n    console.log(\u2019\u30d6\u30ed\u30c3\u30af\u5185\u306e let \u306e\u578b = \u2019 + typeof let_value);\n    console.log(\u2019\u30d6\u30ed\u30c3\u30af\u5185\u306e const \u306e\u578b = \u2019 + typeof const_value);\n  }\n\n  console.log(\u2019-----\u30d6\u30ed\u30c3\u30af\u5916-----\u2019);\n  console.log(\u2019\u30d6\u30ed\u30c3\u30af\u5916\u306e var \u306e\u578b = \u2019 + typeof var_value);\n  console.log(\u2019\u30d6\u30ed\u30c3\u30af\u5916\u306e let \u306e\u578b = \u2019 + typeof let_value);\n  console.log(\u2019\u30d6\u30ed\u30c3\u30af\u5916\u306e const \u306e\u578b = \u2019 + typeof const_value);\n\n})();\n\nconsole.log(\u2019-----\u95a2\u6570\u5916-----\u2019);\nconsole.log(\u2019\u95a2\u6570\u5916\u306e var \u306e\u578b = \u2019 + typeof var_value);\nconsole.log(\u2019\u95a2\u6570\u5916\u306e let \u306e\u578b = \u2019 + typeof let_value);\nconsole.log(\u2019\u95a2\u6570\u5916\u306e const \u306e\u578b = \u2019 + typeof const_value);\n<\/pre>\n
\u3061\u306a\u307f\u306b\u3001console.log \u306e\u4e2d\u3067\u3001\u76f4\u63a5\u5024\u3092\u51fa\u529b\u3059\u308b\u306e\u3067\u306f\u306a\u304f\u3066\u3001typeof \u3092\u4f7f\u7528\u3057\u3066\u3044\u308b\u306e\u306f\u3001
\n\u672a\u5b9a\u7fa9\u306e\u5909\u6570\u304b\u3089\u5024\u3092\u53d6\u308a\u51fa\u305d\u3046\u3068\u3059\u308b\u3068\u30a8\u30e9\u30fc\u3067\u51e6\u7406\u304c\u6b62\u307e\u3063\u3066\u3057\u307e\u3046\u304b\u3089\u3067\u3059\u3002<\/p>\n
\u4eca\u56de\u306f\u5909\u6570\u306b\u6587\u5b57\u5217\u3092\u5165\u308c\u3066\u3044\u307e\u3059\u306e\u3067\u3001
\n\u5909\u6570\u304c\u304d\u3061\u3093\u3068\u5b58\u5728\u3057\u3066\u3044\u308c\u3070 string<\/code> \u3067\u3001
\n\u5b58\u5728\u3057\u306a\u3044\u5909\u6570\u306b\u5bfe\u3057\u3066 typeof \u3092\u3059\u308b\u3068 undefined<\/code> \u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n
\u3053\u308c\u3092\u5b9f\u884c\u3059\u308b\u3068\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u7d50\u679c\u304c\u51fa\u307e\u3059\u3002<\/p>\n
\n-----\u30d6\u30ed\u30c3\u30af\u5185-----\n\u30d6\u30ed\u30c3\u30af\u5185\u306e var \u306e\u578b = string\n\u30d6\u30ed\u30c3\u30af\u5185\u306e let \u306e\u578b = string\n\u30d6\u30ed\u30c3\u30af\u5185\u306e const \u306e\u578b = string\n\n-----\u30d6\u30ed\u30c3\u30af\u5916-----\n\u30d6\u30ed\u30c3\u30af\u5916\u306e var \u306e\u578b = string\n\u30d6\u30ed\u30c3\u30af\u5916\u306e let \u306e\u578b = undefined\n\u30d6\u30ed\u30c3\u30af\u5916\u306e const \u306e\u578b = undefined\n\n-----\u95a2\u6570\u5916-----\n\u95a2\u6570\u5916\u306e var \u306e\u578b = undefined\n\u95a2\u6570\u5916\u306e let \u306e\u578b = undefined\n\u95a2\u6570\u5916\u306e const \u306e\u578b = undefined\n<\/pre>\n
\u3053\u3053\u3067\u3001\u30d6\u30ed\u30c3\u30af\u3068\u306f\u4e2d\u62ec\u5f27 {} \u306e\u3053\u3068\u3067\u3059\u306d\u3002
\n\u30d6\u30ed\u30c3\u30af\u306e\u4e2d\u3067\u5909\u6570\u3092\u5ba3\u8a00\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n
\u3067\u3001\u540c\u3058\u30d6\u30ed\u30c3\u30af\u5185\u3067\u305d\u308c\u305e\u308c\u5909\u6570\u3092\u53c2\u7167\u3057\u305f\u7d50\u679c\u3092\u898b\u3066\u307f\u308b\u3068\u3001\u5168\u3066 string \u306b\u306a\u3063\u3066\u3044\u307e\u3059\u3002
\n\u3059\u306a\u308f\u3061\u3001\u4e0a\u3067\u5ba3\u8a00\u3055\u308c\u305f\u5909\u6570\u304c\u898b\u3048\u3066\u3044\u308b\u72b6\u614b\u3067\u3059\u306d\u3002
\n\u3053\u3053\u307e\u3067\u306f\u666e\u901a\u306b\u60f3\u5b9a\u3055\u308c\u308b\u52d5\u304d\u3067\u3059\u3057\u3001\u5927\u4e08\u592b\u3067\u3057\u3087\u3046\u3002<\/p>\n
\u3067\u306f\u3001\u30d6\u30ed\u30c3\u30af\u5916\u306b\u51fa\u308b\u3068\u3069\u3046\u3067\u3057\u3087\u3046\u304b\u3002<\/p>\n
var \u3067\u5ba3\u8a00\u3057\u305f\u5909\u6570\u306f\u4f9d\u7136\u898b\u3048\u3066\u3044\u308b\u3088\u3046\u3067\u3059\u304c\u3001
\nlet, const \u3067\u5ba3\u8a00\u3057\u305f\u5909\u6570\u306f undefined\u3002\u3059\u306a\u308f\u3061\u672a\u5b9a\u7fa9\u3068\u306a\u3063\u3066\u3044\u307e\u3059\u3002
\n\u3053\u308c\u306f\u3001let, const \u306f\u5ba3\u8a00\u3057\u305f\u5909\u6570\u306f\u3001\u540c\u3058\u30d6\u30ed\u30c3\u30af\u5185\u3067\u3057\u304b\u53c2\u7167\u3067\u304d\u306a\u3044\u3053\u3068\u3092\u8868\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n
\u3053\u306e\u3088\u3046\u306b\u3001\u5909\u6570\u306e\u898b\u3048\u308b\u7bc4\u56f2\u3092\u300c\u30b9\u30b3\u30fc\u30d7\u300d\u3068\u3044\u3046\u306e\u3067\u3059\u306d\u3002
\n\u3061\u306a\u307f\u306b\u3001\u3053\u306e\u3088\u3046\u306b\u30d6\u30ed\u30c3\u30af\u3067\u30b9\u30b3\u30fc\u30d7\u304c\u533a\u5207\u3089\u308c\u308b\u3053\u3068\u3092\u300c\u30d6\u30ed\u30c3\u30af\u30b9\u30b3\u30fc\u30d7\u300d\u3068\u8a00\u3044\u307e\u3059\u3002
\n\u307e\u3093\u307e\u3067\u3059\u306d\u3002<\/p>\n
\u3055\u3066\u6b21\u306b\u3001\u3055\u3089\u306b\u305d\u306e\u5916\u306e\u95a2\u6570\u3092\u51fa\u308b\u3068\u3069\u3046\u3067\u3057\u3087\u3046\u304b\u3002
\n\u3053\u306e\u5834\u5408\u306f\u5f53\u7136 let, const \u3067\u5ba3\u8a00\u3057\u305f\u5909\u6570\u306f\u898b\u3048\u3066\u3044\u307e\u305b\u3093\u3002
\n\u52a0\u3048\u3066\u3001 var \u3067\u5ba3\u8a00\u3057\u305f\u5909\u6570\u3082\u898b\u3048\u306a\u304f\u306a\u308a\u307e\u3057\u305f\u306d\u3002<\/p>\n
\u3064\u307e\u308a\u3001var \u306f\u95a2\u6570\u3067\u30b9\u30b3\u30fc\u30d7\u304c\u533a\u5207\u3089\u308c\u308b\u3001\u300c\u30d5\u30a1\u30f3\u30af\u30b7\u30e7\u30f3\u30b9\u30b3\u30fc\u30d7\u300d\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/p>\n
\u203b\u3061\u306a\u307f\u306b\u3001\u5909\u6570\u306f\u30b9\u30b3\u30fc\u30d7\u306e\u5916\u306b\u51fa\u308b\u3068\u898b\u3048\u306a\u304f\u306a\u308a\u307e\u3059\u304c\u3001
\n\u5916\u3067\u5ba3\u8a00\u3055\u308c\u305f\u5909\u6570\u306f\u30b9\u30b3\u30fc\u30d7\u306e\u4e2d\u306b\u5165\u3063\u3066\u3082\u898b\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n
\u3064\u307e\u308a\u3001<\/p>\n
\n(function () {\n  let let_value = \u2019let\u2019;\n\n  {    \n    console.log(\u2019\u30d6\u30ed\u30c3\u30af\u5185\u306e let \u306e\u578b = \u2019 + typeof let_value);\n  } \n})();\n<\/pre>\n
\u3053\u308c\u306f<\/p>\n
\n\u30d6\u30ed\u30c3\u30af\u5185\u306e let \u306e\u578b = string\n<\/pre>\n
\u3068\u51fa\u529b\u3055\u308c\u307e\u3059\u3002<\/p>\n
\u30b9\u30b3\u30fc\u30d7\u306f\u300c\u5f71\u97ff\u7bc4\u56f2\u304c\u5916\u306b\u5e83\u304c\u3063\u3066\u3044\u304b\u306a\u3044\u3088\u3046\u306b\u3059\u308b\u300d\u6a5f\u80fd\u3060\u3068\u601d\u3046\u3068\u308f\u304b\u308a\u3084\u3059\u3044\u3067\u3059\u306d\u3002<\/p>\n
\u30b0\u30ed\u30fc\u30d0\u30eb\u5909\u6570\u306e\u3001window \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3078\u306e\u8ffd\u52a0<\/h2>\n
\u4e09\u3064\u76ee\u306f\u30b0\u30ed\u30fc\u30d0\u30eb\u5909\u6570\u306e\u5f71\u97ff\u7bc4\u56f2\u3067\u3059\u3002<\/p>\n
\u30b0\u30ed\u30fc\u30d0\u30eb\u5909\u6570\u3068\u306f\u3001\u3069\u3053\u304b\u3089\u3067\u3082\u53c2\u7167\u304c\u3067\u304d\u308b\u5909\u6570\u3067\u3059\u306d\u3002
\n\u5148\u307b\u3069\u306e\u30b9\u30b3\u30fc\u30d7\u306e\u8a71\u3092\u8003\u3048\u308c\u3070\u3001\u4e00\u756a\u5916\u5074\u306e\u30b9\u30b3\u30fc\u30d7\u3001\u5168\u3066\u306e\u30d6\u30ed\u30c3\u30af\u3084\u95a2\u6570\u306e\u5916\u5074\u306b\u66f8\u3051\u3070\u826f\u3044\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/p>\n
\u3055\u3066\u3001\u305d\u306e\u30b0\u30ed\u30fc\u30d0\u30eb\u5909\u6570\u3068\u3057\u3066\u3001\u30d6\u30e9\u30a6\u30b6\u304c\u4e88\u3081\u7528\u610f\u3057\u3066\u3044\u308b\u3082\u306e\u306b\u3001 window<\/code> \u3068\u3044\u3046\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u304c\u3042\u308a\u307e\u3059\u3002
\nwindow \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u306f\u3001\u4eca\u958b\u3044\u3066\u3044\u308b\u30da\u30fc\u30b8\u306e\u60c5\u5831\u3084\u30d6\u30e9\u30a6\u30b6\u306e\u30b5\u30a4\u30ba\u306e\u60c5\u5831\u306a\u3069\u3001\u69d8\u3005\u306a\u60c5\u5831\u304c\u683c\u7d0d\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n
\u3055\u3066\u3001\u305d\u306e window \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3068\u306f\u5168\u304f\u95a2\u4fc2\u306a\u3044\u3068\u3053\u308d\u3067\u3001
\n\u30b0\u30ed\u30fc\u30d0\u30eb\u5909\u6570\u3092\u3053\u3061\u3089\u304b\u3089\u5b9a\u7fa9\u3057\u3066\u307f\u307e\u3059\u3068\u2026<\/p>\n
\nvar var_value = \u2019var\u2019;\nlet let_value = \u2019let\u2019;\nconst const_value = \u2019const\u2019;\n\nconsole.log(\u2019window \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e var = \u2019 + window.var_value);\nconsole.log(\u2019window \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e let =\u2019 + window.let_value);\nconsole.log(\u2019window \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e const = \u2019 + window.const_value);\n<\/pre>\n
\u4e0a\u3092\u5b9f\u884c\u3057\u305f\u7d50\u679c\u304c\u3053\u3061\u3089<\/p>\n
\nwindow \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e var = var\nwindow \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e let =undefined\nwindow \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e const = undefined\n<\/pre>\n
\u306a\u3093\u3068\u3001\u306a\u305c\u304b var \u3067\u30b0\u30ed\u30fc\u30d0\u30eb\u5909\u6570\u3092\u5ba3\u8a00\u3057\u305f\u5834\u5408\u306f\u3001window \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u304b\u3089\u53c2\u7167\u3067\u304d\u3066\u3057\u307e\u3044\u307e\u3059\uff01
\n\u305d\u308c\u3060\u3051\u3068\u8a00\u3048\u3070\u305d\u308c\u3060\u3051\u3067\u3059\u3057\u3001\u305d\u3082\u305d\u3082\u30b0\u30ed\u30fc\u30d0\u30eb\u5909\u6570\u3092\u4f7f\u3046\u306e\u304c\u4e91\u3005\u3068\u3044\u3046\u8a71\u3082\u3042\u308a\u307e\u3059\u304c\u3001
\n\u610f\u5916\u306a\u6319\u52d5\u3067\u306f\u3042\u308b\u306e\u3067\u306f\u306a\u3044\u3067\u3057\u3087\u3046\u304b\u3002<\/p>\n
var \u3092\u4f7f\u308f\u306a\u3044\u7406\u7531\u2026\u305d\u308c\u306f\u5f71\u97ff\u7bc4\u56f2\u3092\u72ed\u304f\u3059\u308b\u305f\u3081\uff01<\/h1>\n
\u3055\u3066\u3001\u3053\u3053\u307e\u3067\u3067\u3001 var \u3068 let & const \u3068\u306e\u9055\u3044\u3092\u898b\u3066\u304d\u307e\u3057\u305f\u3002<\/p>\n
\u3059\u3067\u306b\u304a\u6c17\u3065\u304d\u306e\u65b9\u3082\u3044\u3089\u3063\u3057\u3083\u308b\u304b\u3068\u601d\u3044\u307e\u3059\u304c\u3001
\n\u3069\u308c\u3082 var \u3067\u306f\u3067\u304d\u3066\u3044\u305f\u3053\u3068\u304c let, const \u3067\u306f\u3067\u304d\u306a\u304f\u306a\u3063\u3066\u3044\u308b\u306e\u3067\u3059\u306d\u3002<\/p>\n
\u3053\u308c\u306f\u3001\u5909\u6570\u5b9a\u7fa9\u306b\u95a2\u9023\u3059\u308b\u30df\u30b9\u3092\u6975\u529b\u6e1b\u3089\u3059\u305f\u3081\u3001
\n\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u4eba\u304c\u898b\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u7bc4\u56f2\u3092\u6e1b\u3089\u3059\u3001\u3068\u8a00\u3046\u52b9\u679c\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n
var \u3092\u4f7f\u3063\u3066\u3044\u305f\u3068\u304d\u306b\u306f\u767a\u751f\u3057\u3066\u3044\u305f\u3001\u601d\u308f\u306c\u4e8b\u6545\u3092 let, const \u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u9632\u3050\u3053\u3068\u304c\u3067\u304d\u308b\u306e\u3067\u3059\u306d\uff01<\/p>\n
\u7686\u3055\u3093\u3082\u3001JS \u3067\u306e\u5909\u6570\u5b9a\u7fa9\u306f let, const \u3092\u4f7f\u3046\uff01\u3068\u899a\u3048\u3066\u304a\u3044\u3066\u304f\u3060\u3055\u3044\u306d\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
JS \u306e\u5909\u6570\u5b9a\u7fa9\u3067\u306f let, const \u3092\u4f7f\u3046\u3079\u3057\uff01\u2026\u3063\u3066\u4f55\u3067\uff1f JavaScript \u306f\u6700\u8fd1\u8272\u3005\u3068\u9032\u5316\u3057\u3066\u304d\u3066\u3044\u307e\u3059\u3088\u306d\u3002 \u3067\u3001\u6700\u8fd1\u306e JS \u306e\u66f8\u304d\u65b9\u3068\u3057\u3066\u3088\u304f\u8a00\u308f\u308c\u3066\u3044\u308b\u306e\u306f\u3001 \u300c\u5909\u6570\u5b9a\u7fa9\u3067\u306f var \u3067\u306f\u306a\u304f\u3066 […]<\/p>\n","protected":false},"author":15,"featured_media":14346,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[10],"tags":[45],"class_list":["post-14342","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tech","tag-javascript"],"jetpack_featured_media_url":"https:\/\/www.agent-grow.com\/self20percent\/wp-content\/uploads\/2019\/06\/850c7612116999490846136e772ab7fd-1.png","jetpack_shortlink":"https:\/\/wp.me\/p7Bq4F-3Jk","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/posts\/14342","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/users\/15"}],"replies":[{"embeddable":true,"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/comments?post=14342"}],"version-history":[{"count":0,"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/posts\/14342\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/media\/14346"}],"wp:attachment":[{"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/media?parent=14342"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/categories?post=14342"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.agent-grow.com\/self20percent\/wp-json\/wp\/v2\/tags?post=14342"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}