ECMAScript 6 新特性之-函数块级作用域
Lasted 2020-01-10 13:48:19
ES6 中函数块级作用域有新的写法,跟 ES5 的差别如下:
//ES6
{
function foo () { return 1 }
foo() === 1
{
function foo () { return 2 }
foo() === 2
}
foo() === 1
}
// only in ES5 with the help of block-scope emulating
// function scopes and function expressions
(function () {
var foo = function () { return 1; }
foo() === 1;
(function () {
var foo = function () { return 2; }
foo() === 2;
})();
foo() === 1;
})();