function getJSON(url, callback) {
let xhr = new XMLHttpRequest();
xhr.onload = function () {
callback(this.responseText)
};
xhr.open(“GET”, url, true);
xhr.send();
}
export function getUsefulContents(url, callback) {
getJSON(url, data => callback(JSON.parse(data)));
}
import { getUsefulContents } from “file”;
getUsefulContents(“http://www.richerp.net”, data => {
doSomethingUseful(data);
});
export default function() {}
function a() {};
export {a as default};
import a from ‘./d’;
import {default as a} from ‘./d’;
这个语法糖的好处就是import的时候,可以省去花括号{}。
import $,{each,map} from ‘jquery’;
import后面第一个$是{defalut as $}的替代写法。
var a = function() {};
export {a as fun};
import {fun as a} from ‘./a’;
a();