{"id":2465,"date":"2023-04-26T14:17:19","date_gmt":"2023-04-26T05:17:19","guid":{"rendered":"https:\/\/hajimesan.net\/blog\/?p=2465"},"modified":"2023-04-26T14:17:38","modified_gmt":"2023-04-26T05:17:38","slug":"javascript-var-%e3%81%ae%e4%bb%a3%e3%82%8f%e3%82%8a%e3%81%ab-let-%e3%82%92%e4%bd%bf%e3%81%86%e3%81%b9%e3%81%8d%e3%81%8b","status":"publish","type":"post","link":"https:\/\/hajimesan.net\/blog\/?p=2465","title":{"rendered":"[JavaScript] var \u306e\u4ee3\u308f\u308a\u306b let \u3092\u4f7f\u3046\u3079\u304d\u304b"},"content":{"rendered":"\n<pre class=\"wp-block-code\"><code>function foo() {\r\n  let x = 10;\r\n  var z = 30;\r\n  if (true) {\r\n    let y = 20;\r\n    var z = 40;\r\n    console.log(x); \/\/ Output: 10\r\n    console.log(y); \/\/ Output: 20\r\n    console.log(z); \/\/ Output: 40\r\n  }\r\n  console.log(x); \/\/ Output: 10\r\n\/\/  console.log(y); \/\/ Uncaught ReferenceError: y is not defined\r\n  console.log(z); \/\/ Output: 40\r\n}\r\n\r\nfoo();\r\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">ChatGPT\u304c\u5410\u304d\u51fa\u3057\u305f\u30b3\u30fc\u30c9\u306b\u5c11\u3057\u624b\u3092\u52a0\u3048\u305f\u3082\u306e\u3060\u304c\u3001\u3053\u308c(\u5909\u6570z)\u3092\u898b\u3066\u308f\u304b\u308b\u3088\u3046\u306b\u3001var \u306f\u5165\u308c\u5b50\u3067\u5ba3\u8a00\u3067\u304d\u308b\u304f\u305b\u306b\u3001\u95a2\u6570\u30b9\u30b3\u30fc\u30d7\u306a\u306e\u3067\u3001\u5185\u5074\u30d6\u30ed\u30c3\u30af\u3067\u306f\u4e0a\u66f8\u304d\u5ba3\u8a00\u306b\u306a\u3063\u3066\u3057\u307e\u3046\u3002\u3053\u3093\u306a\u3053\u3068\u8a31\u3055\u308c\u3066\u3088\u3044\u306e\u304b\uff1f\u3068\u601d\u3046\u4eba\u3082\u3044\u308b\u3068\u601d\u3046\u304c\u3001\u95a2\u6570\u30b9\u30b3\u30fc\u30d7\u306a\u3089\u305d\u306e\u95a2\u6570\u5185\u3067\u8907\u6570\u306e\u5ba3\u8a00\u304c\u3042\u3063\u305f\u3089\u30a8\u30e9\u30fc\u306b\u306a\u3063\u3066\u6b32\u3057\u3044\u3057\u3001\u8907\u6570\u5ba3\u8a00\u3067\u304d\u308b\u306a\u3089\u30d6\u30ed\u30c3\u30af\u30b9\u30b3\u30fc\u30d7\u306b\u3057\u3066\u6b32\u3057\u3044\u3002\u3068\u3044\u3046\u3053\u3068\u304b\u3089\u3001let \u304c\u8ffd\u52a0\u3055\u308c\u305f\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3056\u3063\u304f\u308a\u3068\u8a00\u3048\u3070\u3001var \u306e\u76f4\u611f\u7684\u3067\u306f\u306a\u3044\u304a\u304b\u3057\u306a\u6319\u52d5\u3092\u3057\u306a\u3044\u3088\u3046\u306b\u3057\u305f\u3082\u306e\u304clet \u3060\u3068\u3082\u8a00\u3048\u308b\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u306a\u306e\u3067\u3001\u3053\u308c\u304b\u3089\u306f\u3001\u3069\u3046\u8003\u3048\u3066\u3082 let \u3092\u4f7f\u3046\u3079\u304d\u3067\u3001var \u3067\u7121\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u7406\u7531\u304c\u898b\u5f53\u305f\u3089\u306a\u3044\u3002\u306e\u3060\u304c\u3001\u307e\u3060\u3001var \u6d3e\u306e\u958b\u767a\u8005\u304c\u5c11\u306a\u304b\u3089\u305a\u5c45\u308b\u3002\u79c1\u306f\u3068\u3044\u3046\u3068\u3001let \u6d3e\u3067\u306f\u3042\u308b\u306e\u3060\u304c\u3001\u3064\u3044\u3064\u3044\u3001\u7656\u3067var \u3068\u66f8\u3044\u3066\u3057\u307e\u3046\u30d8\u30dc\u30d7\u30ed\u30b0\u30e9\u30de\u3068\u3044\u3063\u305f\u3068\u3053\u308d\u3060\u3002\u7279\u306b\u65e2\u5b58\u306e var \u3060\u3089\u3051\u306e\u4ed6\u4eba\u306e\u30d7\u30ed\u30b0\u30e9\u30e0\u3092\u30e1\u30f3\u30c6\u30ca\u30f3\u30b9\u3059\u308b\u6642\u306f\u3001\u4e0b\u624b\u306b let \u306b\u5909\u3048\u305f\u3089\u3001\u52d5\u304b\u306a\u304f\u306a\u308b\u306e\u3067\u306f\u306a\u3044\u304b\u3068\u3044\u3046\u6050\u6016\u5fc3\u304c\u308f\u304f\u3053\u3068\u3082\u3042\u308b\u3002\u52d5\u304b\u306a\u304b\u3063\u305f\u3089\u307b\u307c\u5143\u30d0\u30b0\u306a\u306e\u3060\u304c\u3001\u3081\u3061\u3083\u304f\u3061\u3083\u8907\u96d1\u602a\u5947\u306a\u3082\u306e\u3060\u3068\u3001\u30d0\u30b0\u53d6\u308a\u3092\u3059\u308b\u306e\u3082\u9762\u5012\u306a\u306e\u3067\u3001var \u3067\u9003\u3052\u3066\u3057\u307e\u3046\u3053\u3068\u3082\u3042\u308b\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5927\u3057\u305f\u4f7f\u3044\u5206\u3051\u7684\u610f\u5473\u3082\u306a\u304f\u3001var \u3068 let \u304c\u6df7\u5728\u3059\u308b\u72b6\u6cc1\u3082\u3001\u3042\u307e\u308a\u3088\u304f\u306a\u3044\u3068\u306f\u601d\u3046\u3068\u3044\u3046\u3053\u3068\u3082\u3001var \u3092\u4f7f\u3044\u304c\u3061\u306b\u306a\u308b\u8981\u56e0\u3068\u8a00\u3048\u308b\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>ChatGPT\u304c\u5410\u304d\u51fa\u3057\u305f\u30b3\u30fc\u30c9\u306b\u5c11\u3057\u624b\u3092\u52a0\u3048\u305f\u3082\u306e\u3060\u304c\u3001\u3053\u308c(\u5909\u6570z)\u3092\u898b\u3066\u308f\u304b\u308b\u3088\u3046\u306b\u3001var \u306f\u5165\u308c\u5b50\u3067\u5ba3\u8a00\u3067\u304d\u308b\u304f\u305b\u306b\u3001\u95a2\u6570\u30b9\u30b3\u30fc\u30d7\u306a\u306e\u3067\u3001\u5185\u5074\u30d6\u30ed\u30c3\u30af\u3067\u306f\u4e0a\u66f8\u304d\u5ba3\u8a00\u306b\u306a\u3063\u3066\u3057\u307e\u3046\u3002\u3053\u3093\u306a\u3053\u3068\u8a31\u3055\u308c\u3066\u3088\u3044\u306e\u304b\uff1f\u3068 &hellip; <a href=\"https:\/\/hajimesan.net\/blog\/?p=2465\">\u7d9a\u304d\u3092\u8aad\u3080 <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_crdt_document":"","footnotes":""},"categories":[3],"tags":[],"class_list":["post-2465","post","type-post","status-publish","format-standard","hentry","category-zakki"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2465","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2465"}],"version-history":[{"count":2,"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2465\/revisions"}],"predecessor-version":[{"id":2467,"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2465\/revisions\/2467"}],"wp:attachment":[{"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2465"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2465"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hajimesan.net\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2465"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}