(window.webpackJsonp=window.webpackJsonp||[]).push([[112],{442:function(s,t,a){"use strict";a.r(t);var n=a(3),e=Object(n.a)({},(function(){var s=this,t=s._self._c;return t("ContentSlotsDistributor",{attrs:{"slot-key":s.$parent.slotKey}},[t("h1",{attrs:{id:"编程风格"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#编程风格"}},[s._v("#")]),s._v(" 编程风格")]),s._v(" "),t("p",[s._v("本章探讨如何将 ES6 的新语法,运用到编码实践之中,与传统的 JavaScript 语法结合在一起,写出合理的、易于阅读和维护的代码。")]),s._v(" "),t("p",[s._v("多家公司和组织已经公开了它们的风格规范,下面的内容主要参考了 "),t("a",{attrs:{href:"https://github.com/airbnb/javascript",target:"_blank",rel:"noopener noreferrer"}},[s._v("Airbnb"),t("OutboundLink")],1),s._v(" 公司的 JavaScript 风格规范。\n")]),s._v(" "),t("h2",{attrs:{id:"块级作用域"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#块级作用域"}},[s._v("#")]),s._v(" 块级作用域")]),s._v(" "),t("p",[t("strong",[s._v("(1)let 取代 var")])]),s._v(" "),t("p",[s._v("ES6 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"),t("div",{staticClass:"line-numbers-wrapper"},[t("span",{staticClass:"line-number"},[s._v("1")]),t("br"),t("span",{staticClass:"line-number"},[s._v("2")]),t("br"),t("span",{staticClass:"line-number"},[s._v("3")]),t("br"),t("span",{staticClass:"line-number"},[s._v("4")]),t("br"),t("span",{staticClass:"line-number"},[s._v("5")]),t("br"),t("span",{staticClass:"line-number"},[s._v("6")]),t("br"),t("span",{staticClass:"line-number"},[s._v("7")]),t("br"),t("span",{staticClass:"line-number"},[s._v("8")]),t("br")])]),t("p",[s._v("使用 ESLint 检查这个文件,就会报出错误。")]),s._v(" "),t("div",{staticClass:"language-bash line-numbers-mode"},[t("pre",{pre:!0,attrs:{class:"language-bash"}},[t("code",[s._v("$ eslint index.js\nindex.js\n "),t("span",{pre:!0,attrs:{class:"token number"}},[s._v("1")]),s._v(":1 error Unexpected var, use "),t("span",{pre:!0,attrs:{class:"token builtin class-name"}},[s._v("let")]),s._v(" or const instead no-var\n "),t("span",{pre:!0,attrs:{class:"token number"}},[s._v("1")]),s._v(":5 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