JSLint：超出三元变量集的范围 [英] JSLint: used out of scope for ternary variable set

问题描述

我有这样的代码块：

/*global MYAPP: true*/
var MYAPP = MYAPP || {};

JSLint在等号后突出显示 MYAPP，并显示消息 MYAPP已超出范围。

JSLint highlights "MYAPP" after equal sign with message "MYAPP used out of scope".

这有什么问题？

推荐答案

如果您使用 var ，则您声明一个局部变量。
如果您执行 MYAPP || {} ，那么您通常会尝试为全局变量或先前声明的变量设置默认值。

If you use var then you are declaring a local variable. If you do MYAPP || {} then you are typically trying to set a default value for a global variable, or for a variable declared earlier.

范围是什么 MYAPP 应该是？如果是全局的，则类似

What is the scope of MYAPP supposed to be? If it is global, then something like

MYAPP = window.MYAPP || {}; 

窗口。阻止它抱怨它是未定义的

window. stops it from complaining that it is undefined

如果它不是全局的但声明得更早，则

If it is not global but declared earlier, then

MYAPP = MYAPP || {};

如果这是该行所属函数的局部变量，则

If it is a new variable local to the function that this line is part of then

var MYAPP = {};

如果您在脚本的顶层定义了变量（即不在函数中），那是全球性的如果您在两个具有相同名称的不同脚本标记（或javascript文件）中具有全局变量，则它们是相同的变量。
如果要从其他脚本标签（或javascript文件）隐藏变量，请考虑使用IIFE（立即调用的函数表达式）。例如

If you have a variable defined at the top level of your script (i.e. not in a function), then it is a global. If you have global variables in two different script tags (or javascript files) with the same name, then they are the same variable. If you want to hide a variable from other script tags (or javascript files), consider using an IIFE (immediately invoked function expression). e.g.

(function() {
    var MYAPP = {};
    //code that uses MYAPP;
})();
//MYAPP is not visible out here, or in other script tags/files.

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