es6 import笔记

export输出：

// profile.js
var firstName = 'Michael';
var lastName = 'Jackson';
var year = 1958;

export {firstName, lastName, year};

function v1() { ... }
function v2() { ... }

export {
  v1 as streamV1,
  v2 as streamV2,
  v2 as streamLatestVersion
};

// main.js
import {firstName, lastName, year} from './profile.js';

function setName(element) {
  element.textContent = firstName + ' ' + lastName;
}

整体加载：

import * as circle from './circle';

console.log('圆面积：' + circle.area(4));
console.log('圆周长：' + circle.circumference(14));

export default:

// export-default.js
export default function () {
  console.log('foo');
}

// import-default.js
import customName from './export-default';
customName(); // 'foo'