Ejemplos de la charla Una tapa de EcmaScript. PPT http://www.slideshare.net/eduardtomas/una-tapa-de-ecmascript-6

01_1Scope.js

(function() {
	const a=10;
	a=20;
	let b=10;
	b=20;
	console.log("a-->" + a);
	console.log("b-->" + b);
	var s = true;
	while (s) {
		const ic = 10;
		var gic = 10;
		s = false;
	}

	console.log("gic-->" + gic);
	console.log("ic-->" + ic);	 
})();

01_2Const.js

(function() {
	for (let i=0; i<2; i++) {
		console.log("i-->" + i);
	}

	for (var gi=0; gi<2; gi++) {
		console.log("gi-->" + gi);
	}

	console.log("i-->" + i);
	console.log("gi-->" + gi);
})();

02_Destructuring.js

(function() {
	var [a, b, c] = [10, 20, 30];
	console.log("a-->", a);
	console.log("b-->", b);
	console.log("c-->", c);

	var [,d,,e] = [10,20, 30, 40];
	console.log("d-->", d);
	console.log("e-->", e);

	function fibo() {
		return [1,1,2,3,5,8];
	}

	var [,f,,g] = fibo();
	console.log("f-->", f);
	console.log("g-->", g);

	var {m: month, y: year } = {m: 10, y: 20};
	console.log("month-->", month);

	function now() {
		return {y:2014, m:12, d:26};
	}

	var {m: fmonth, y: fyear } = now();
	console.log("fmonth-->", fmonth);
})();

03_1OptionalPars.js

(function() {
	function foo(a,b) {
		console.log("foo.a-->",a);
		console.log("foo.b->",b);

		console.log("foo.args-->", arguments.length);
	}
	function optfoo(a, b=10) {
		console.log("optfoo.a-->",a);
		console.log("optfoo.b->",b);

		console.log("optfoo.args-->", arguments.length);
	}

	foo(5);
	optfoo(5);

})();

03_2Variadic.js

(function() {
	function variadic(a,b,...v) {
		console.log("a-->", a);
		console.log("b-->", b);
		console.log("v-->", v);
		console.log("----");
	}

	variadic(1,2);
	variadic(1,2,3);
	variadic(1,2,3,4,5,6,7);
})();

04_1Spread.js

(function() {
	var a = [1,2,3,4];

	function foo(x, y, ...z) {
		console.log("x-->", x);
		console.log("y-->", y);
		console.log("z-->", z);
	}

	foo(10, 20, a);
	foo (10, 20,...a);

})();

04_2SpreadDest.js

(function() {
	let [a, b, ...c] = [10, 20, 30, 40, 50];
	console.log(c);
})();

04_3BetterPush.js

(function() {
	var a = [1,2,3];
	var b = [4,5,6];

	// Modo ES5 de añadir b a a:
	Array.prototype.push.apply(a,b);
	console.log(a);
	
	var a2= [1,2,3];
	a2.push(...b);
	console.log(a2);

})();

05_Arrow.js

(function(){
	var Animal = function() {
		this.age = 10;
		this.grow = () => {
			setInterval( () => console.log(++this.age), 1000);
		};
	}

	var dog = new Animal();
	dog.age = 10;
	dog.grow();
})();

06_Shorthand.js

(function() {
	var url = 'http://www.google.com';
	let one = 1;

	function get_one() {
		return 1;
	}

	var data = {url, method: 'POST', one: get_one()};

	for (let k in data) {
		console.log(k, data[k]);
	}
});

07_1Iterator.js

(function() {
	function arrayIterator() {
		var idx = 0;
		return {
			next: () => {
				return idx < this.length ? 
					{done: false, value: this[idx++]} : 
					{done: true};
			}
		}
	}
	Array.prototype.makeIterator = arrayIterator;
	var iterator = [1,2,3,4].makeIterator();
	console.log(iterator.next().value);
	console.log(iterator.next().value);
})();

08_ForOf.js

(function() {
	var Beers = function() {

		this.data = ["estrella", "voll damm", "guinness"];
		this.iterator = () => {
			var idx = 0;
			return {
				next: () => {
					return idx < this.data.length ? 
						{done: false, value: this.data[idx++]} : 
						{done: true};
				}
			}
		};

		this['@@iterator'] = this.iterator;
	}
	
	var mb = new Beers();

	for (let beer of mb) {
		console.log(beer);
	}
})();

09_1Generators.js

(function() {
	var Beers = function*() {
		yield  "Estrella";
		yield  "Voll Damm";
		yield  "Guinness";
		yield  "Sang de gossa";
	}

	
	var beers = Beers();
	for (let beer of beers) {
		console.log(beer);
	}

	// 1. Es un iterador
	console.log("beers.next is ",typeof(beers.next));

	// 2. es un iterable
	console.log("beers @@iterator is ", typeof(beers['@@iterator']));

	// 3. Podemos usar operator para pasar todas las cervezas a un array
	var allbeers = [...Beers()];
	console.log(allbeers);

	// 4. Generadores se leen una vez
	var allbeersagain = [...beers];
	var allbeersnew = [...Beers()];

	console.log(allbeersagain.length, allbeersnew.length);

})();

09_2Fibo.js

(function() {

	var fibo = function*() {
		let [prev, curr] = [0, 1];
	    while(true) {
	        [prev, curr] = [curr, prev + curr];
	        yield curr;
	    }
	};

	var seq = fibo();

	console.log(seq.next().value);
	console.log(seq.next().value);
	console.log(seq.next().value);
	console.log(seq.next().value);

})();

10_Maps.js

(function() {

	var m = new Map();
	m.set(5, "five");
	m.set("5", "five as string");
	m.set(2, {value: 2});

	console.log(m.has(2));
	console.log(m.has("2"));


	m.forEach((k,v) => console.log("Key is ", k, " and value is ", v));

	for (let kv of m) {
		console.log(kv);
	}

})();

11_Classes.js

(function() {
	class Animal {
		constructor (name) {
			this.name = name;
		}

		toObject() {
			return {name: this.name};
		}
	}

	var dog = new Animal('Puppy');
	console.log(dog.toObjec());
})();

12_Proxies.js

(function() {

	var Beer = function(name, ibus) {
		this.name = name;
		if (ibus) {
			this.ibus = ibus;
		}
	}


	var bhandler = {
		get: function (target, name) {
			return name in target ? target[name] : 42;
		},
		set: function(target, name, value) {
			if (name == "ibus" && value < 100) {
				target[name] = value;
			}
		}
	}

	var pbeer= new Proxy(new Beer('estrella', 15), bhandler)
	var pbeer2 = new Proxy(new Beer('volldamm'), bhandler)
	console.log(pbeer.name, pbeer.ibus);
	console.log(pbeer2.name, pbeer2.ibus);
	pbeer2.ibus = 1000;
	console.log(pbeer2.ibus);
	pbeer2.ibus=10;
	console.log(pbeer2.ibus);
	
})();