1. EcmaScript 5.1 MASTERING NAMESPACES! Илья Кантор http://javascript.ru

2. История

3. varuser=<username="John"> <fieldtype="age"value="25"/> <fieldtype="email"value="john@gmail.com"/> </user> alert(user.field.(@type=="email").@value) 1997 ECMA-262 1st edition 1999 ECMA-2623rd edition 2001 Compact Profile 2004 E4X — ECMA-262 4th ed. 2009 ECMA-2625th edition ??? — ECMA-262Harmony

4. ECMA-2625th edition Что нового?

5. ECMA-2625th edition Багфиксы

6. obj={ class:'Menu' } ES3: ошибка ES5: ok

7. functiontest(str){ varre=/ok/g alert(re.test(str)) } test("ok") test("ok") // true // ES3: false, ES5: true

8. alert(parseInt("010")==parseFloat("010")) ES3: false ES5: true

9. varobj={ a:1, b:2, } vararr[1,2,3,] ES3: error ES5: ok

10. МетаСвойства

11. writable = false obj={ class:'Menu' } obj.class='Bird‘ =>obj.class == ‘Menu’

12. configurable = false obj={ class:'Menu' } deleteobj.class =>obj.class == ‘Menu’

13. enumerable = false Object.prototype.each=... for(propin{}){ // без свойства ‘each’ }

14. Объявление Object.defineProperty({},"class", { value:"Menu", writable:false, configurable:false, enumerable:true }) => { “class” : “Menu” } property descriptor

15. Объявление Object.defineProperties({},{ class:{ value:"Menu", writable:false, configurable:false }, height:{ value:200, configurable:false } }) => { “class” : “Menu”, “height”: 200 }

16. Закрытие объекта varuser={ name:"Вася", /* ... */ } Object.preventExtensions(user) user.a=5// Нельзя добавлять свойства Object.seal(user) deleteuser.name// Нельзя удалять свойства Object.freeze(user) user.name='Петя'// Нельзя менять свойства

17. Наследование animal={ canWalk:true } rabbit=Object.create(animal,{ canRun:{ value:true } }) alert(rabbit.canWalk)// true Object.getPrototypeOf(rabbit) == animal // true

18. Наследование rabbit=Object.create(animal,{ canRun:{ value:true } }) bird=Object.create(Object.getPrototypeOf(rabbit),{ canFly:{ value:true } })

19. Геттеры и Сеттеры user=Object.defineProperty({},"fullName",{ get:function(){ returnthis.firstName+' '+this.lastName }, set:function(value){ vars=value.trim().split(/+/,2) this.firstName=s[0]; this.lastName=s[1] } }) user.fullName="Вася Пупкин" alert(user.lastName)// Пупкин

20. Геттеры и Сеттеры varuser={ getfullName(){ returnthis.firstName+' '+this.lastName }, setfullName(value){ vars=value.trim().split(/+/,2) this.firstName=s[0]; this.lastName=s[1] } } user.fullName="Вася Пупкин" alert(user.lastName)// Пупкин

21. JSON

23. JSON – любые объекты functionRoom(number){ this.toJSON=function(){ returnnumber } } event={ title:"Conference", date:newDate(), room:newRoom(22) } JSON.stringify(event) {"title":"Conference","date":"2011-02-15T09:12:06.836Z","room":22}

24. JSON – любые объекты functionRoom(number){ this.toJSON=function(){ returnnumber } } event={ title:"Conference", date:newDate(), Date.prototype.toJSON room:newRoom(22) } JSON.stringify(event) {"title":"Conference","date":"2011-02-15T09:12:06.836Z","room":22}

25. JSON.stringify(str, whitelist) event={ title:"Conference", date:newDate(), domElement:document.body } JSON.stringify(event) => TypeError: Converting circular structure to JSON JSON.stringify(event,["title","date"]) => {"title":"Conference","date":"2011-02-15T09:44:13.419Z"}

26. JSON.stringify(str, replacer) event={ title:"Conference", date:newDate(), domElement:document.body } JSON.stringify(event,function(key,value){ returnvalue.nodeName?undefined:value }) => {"title":"Conference","date":"2011-02-15T09:44:13.419Z"}

27. JSON.parse(str) str='{"title":"Conference", br /> "date":"2011-02-15T09:44:13.419Z"}' event=JSON.parse(str) пробелы

28. JSON.parse(str) str='{"title":"Conference", br /> "date":"2011-02-15T09:44:13.419Z"}' event=JSON.parse(str) event.date.getDay() => TypeError: no method 'getDay'

29. JSON.parse(str, reviver) str='{"title":"Conference", br /> "date":"2011-02-15T09:44:13.419Z"}' event=JSON.parse(str,function(key,value){ if(key=='date'){ returnnewDate(value) } returnvalue }) event.date.getDay() => 2

30. bind

31. bind(this) functionButton(elem){ this.sayHi=function(){ alert('Hi') } elem.onclick=function(){ this.sayHi() }.bind(this) }

32. bind(this, args) functionButton(elem){ this.say=function(phrase){ alert(phrase) } elem.onclick=function(event,phrase){ this.say(phrase) }.bind(this,'Hi') } @see http://www.prototypejs.org/api/function/bind

33. Strict mode

34. use strict "use strict" ... code ...

35. use strict functionF(){ "use strict" this.method=function(){ // strict mode inherited } }

36. use strict alert(010)// SyntaxError (octal literals deprecated) a=5// ReferenceError (undeclared a) obj.notWritable=...// TypeError deleteobj.notConfigurable// TypeError eval("var a = 5") alert(a)// ReferenceError (undeclared a) arguments.callee// TypeError arguments.caller// TypeError (function(){ alert(this)// undefined вместо window })() with(..)// SyntaxError, 'with' statement

37. Функции,которые давно ждали Object.keys(obj) "String".trim() Array.isArray(arr) [...].indexOf/lastIndexOf [...].forEach [...].map [...].filter [...].reduce/reduceRight // ... @seehttp://kangax.github.com/es5-compat-table/

38. The future is now ? ECMAScript 5 compatibility table ES5-shim

39. Harmony

40. It’s all real __noSuchMethod__Proxy.create letblock_scoped="yay!" constREALLY="srsly" #(x) { x * x } ifx>zreturn"без скобок" moduleIter="@std:Iteration" return[i*iforiinrange(n)] functionprintf(format,...args)ek_scoped= "yay!" consEALLY= "srsly"