ECMAScript 6 簡介

參考自
Introduction to ECMAScript 6
Christophe Coenraets
@ccoenraets

ECMAScript 6 簡介 ECMAScript (ES) 6 = ECMAScript 2015 Cheng-Han Wu @jackymaxj 參考自 Introduction to ECMAScript 6 Christophe Coenraets @ccoenraets

	let firstName = "Christophe";
	let lastName = "Coenraets";
	let twitterId = "@ccoenraets";

	let speaker = {firstName, lastName, twitterId};

	var colors = ["red", "green", "blue", "yellow", "orange"];

	var [primary, secondary, ...otherColors] = colors;

	console.log(primary); // red
	console.log(secondary); // green
	console.log(otherColors); // [ 'blue', 'yellow', 'orange']

	function getDate() {
	var d = new Date();
	return [d.getDate(), d.getMonth() + 1, d.getFullYear()];
	}

	var [day, month, year] = getDate();
	console.log(day); // 4
	console.log(month); // 5
	console.log(year); // 2015

	var speaker = { firstName: "Christophe",
	lastName: "Coenraets",
	twitterId: "@ccoenraets" };

	var firstName = speaker.firstName;
	var lastName = speaker.lastName;
	var twitterId = speaker.twitterId;

	console.log(firstName); // Christophe
	console.log(lastName); // Coenraets
	console.log(twitterId); // @ccoenraets

	var {fName: firstName, lName: lastName, twId:twitterId} = speaker;
	console.log(fName); // Christophe

	var greeting = function(message, name) {
	return message + ' ' + name;
	}

	console.log(greeting('Hello', 'Christophe'));

	var array = [1, 2, 3];
	var total = 0;
	array.forEach(item => total = total + item);
	console.log(total);

	var obj = {
	init: function () {
	var self = this;
	setTimeout(function() {
	self.doSomething();
	}, 1000);
	},
	doSomething: function() {
	console.log("doing something in ES5");
	}
	};
	obj.init();

	var greeting = (name, msg="Hello") => msg + ' ' + name;

	console.log(greeting('Christophe', 'Hi')); // Hi Christophe
	console.log(greeting('Christophe')); // Hello Christophe

	function step1() {
	var deferred = Q.defer();
	FS.readFile("foo.txt", "utf-8", function (error, text) {
	if (error) {
	deferred.reject(new Error(error));
	} else {
	deferred.resolve(text);
	}
	});
	return deferred.promise;
	}

	Q.fcall(step1)
	.then(step2)
	.then(step3)
	.then(step4)
	.then(function(value4) {
	// Do something with value4
	})
	.catch(function(error) {
	// Handle any error from all above steps
	})
	.done();

	var obj = {
	init: function() {
	setTimeout(() => this.doSomething(), 1000);
	},
	doSomething: function() {
	console.log("doing something in ES6");
	}
	};
	obj.init();

	function greeting(name, message="Hello") {
	return message + ' ' + name;
	}

	function timeout(millis) {
	var promise = new Promise(function (resolve, reject) {
	setTimeout(function() {
	resolve();
	}, millis);
	});
	return promise;
	}

	var employees;

	function findAll() {
	return new Promise(function (resolve, reject) {
	if (employees) {
	resolve(employees);
	} else {
	reject("employees is not defined");
	}
	});
	}

	// datelib.js
	export const today = new Date();

	export var shortDate = function() {
	return today.getMonth() + 1 + '/' +
	today.getDate() + '/' +
	today.getFullYear();
	}

	import {today, shortDate} from './datelib';
	console.log(today); // Mon May 4 2015 11:04:06...
	console.log(shortDate()); // 5/4/2015
	import * as date from "./datelib";
	console.log(date.today);
	console.log(date.shortDate());

	export function findAll() {
	// implementation
	}

	export function findById(id) {
	// implementation
	}

	export var endpoint = "http://localhost:5000";

	import * as employeeService from "employee";

	employeeService.findAll().then(function(employees) {
	console.log(employees);
	});

	class Mortgage {

	constructor(amount, years, rate) {
	this.amount = amount;
	this.years = years;
	this.rate = rate;
	}

	calculate() {
	// No interest mortgage for ES6 fans
	return this.amount / (this.years * 12);
	}

	}

	let m = new Mortgage(200000, 30, 3);
	console.log(m.calculate());

	class Circle extends Shape {

	constructor(x, y, radius) {
	super(x, y);
	this.radius = radius;
	}

	static get pi() {
	return 3.14159265359;
	}

	get circumference() {
	return 2 * Circle.pi * this.radius;
	}

	render() {
	console.log('Rendering circle');
	}

	}

	var multiLine = `This is an example
	of a multiline string`;
	console.log(multiLine);

	var user = {firstName: "Lisa", lastName: "Wong"};
	console.log(`Hello, ${user.firstName} ${user.lastName}!`);

	var price = 100;
	var exchangeRate = 0.89;
	console.log(`Price in Euro: ${price * exchangeRate}`);