1.
TC39
theirprocess
and somefeatures

2.
AndréEberhardt
master’s@PUCRS
developer@globoplay
talentos.globo.com
aboutme
we are hiring

3.
-TechnicalCommittee39
-committeethatdesignsECMAScript
-evolvesJavaScript
-amongothers,allmajorbrowservendorsaremembers
TC39

4.
-TechnicalCommittee39
-committeethatdesignsECMAScript
-evolvesJavaScript
-amongothers,allmajorbrowservendorsaremembers
TC39
ECMAScript vs JavaScript?

5.
ecmascriptvsjavascript
javascriptgotthisnameinhopesofcapitalizeonthesuccessofJava
netscapesubmittedjavascripttoECMAInternationalforstandardization
thatresultedinanewlanguagestandard,knownasECMAScript

6.
ecmascriptvsjavascript
javascriptgotthisnameinhopesofcapitalizeonthesuccessofJava
netscapesubmittedjavascripttoECMAInternationalforstandardization
thatresultedinanewlanguagestandard,knownasECMAScript
+ JavaECMA Script

7.
ecmascriptvsjavascript
ECMAScriptisastandard.
JavaScriptisthemostpopularimplementationofthatstandard.
Otherimplementationsinclude:SpiderMonkey,V8,andActionScript.
ECMAScript

8.
-ES1:June1997
-ES2:June1998
-ES3:Dec.1999
-ES4:Abandoned
talkingaboutecmascript

9.
-ES5:Dec.2009
-ES6/ES2015
-ES2016(ES7)
-ES2017(ES8)
-ES2018(ES9)
talkingaboutecmascript
-ES1:June1997
-ES2:June1998
-ES3:Dec.1999
-ES4:Abandoned

10.
-ES5:Dec.2009
-ES6/ES2015
-ES2016(ES7)
-ES2017(ES8)
-ES2018(ES9)
talkingaboutecmascript
-ES1:June1997
-ES2:June1998
-ES3:Dec.1999
-ES4:Abandoned
How does a feature get in?

11.
-theymeetregularly(around6timesayear)
-discussprogressonthependingproposals
-collectivelyworkonmovingforwardwithactiveproposals
-guestsneedapproval
TC39process

12.
TC39maturitystages

13.
-free-formwayofsubmittingideasforevolvingECMAScript
-mustcomefromaTC39memberorcontributor(registered)
-thedocumentmustbereviewedataTC39meeting
TC39stage0:strawman

14.
-formalproposalforthefeature
-achampionmustbeidentifiedasresponsiblefortheproposal
-describetheproblemandthesolutionviaexamples/API
-potentialobstacles
-byacceptingit,TC39declaresitswillingnesstoexamine,discuss
andcontributetotheproposal
TC39stage1:proposal

15.
-firstversionofwhatwillbeinthespecification
-formaldescription
-discussionaboutimplementation
-twoexperimentalimplementations(onecanbeinatranspilerlikebabel)
-fromnowon,onlyincrementalchangesareexpected
-inclusionofthefeatureinthestandardislikely
TC39stage2:draft

16.
-proposalismostlyfinished
-receivesfeedbackfromimplementationsandusers
-spectextmustbecomplete
-reviewersappointedbyTC39mustsignoffonthespectext
-atleasttwospec-compliantimplementations
-fromnowon,changesshouldonlybemadeinresponsetocriticalissues
TC39stage3:candidate

17.
-acceptancetests
-twospec-compliantimplementationsthatpassthetests
-significantpracticalexperiencewiththeimplementations
-oncereachthis,it’sreadytobeincludedinthestandard
TC39stage4:finished

18.
-acceptancetests
-twospec-compliantimplementationsthatpassthetests
-significantpracticalexperiencewiththeimplementations
-oncereachthis,it’sreadytobeincludedinthestandard
TC39stage4:finished
What about the ES**** releases?

19.
- ES****releasesarenotthatimportantnowadays
-stage4proposalsareincludedintheyearlyECMAScriptrelease
assoonaspossible
TC39releases

20.
-thereareproposalsthatreachedstage2,butwerewithdrawn
-onlystage3and4featuresshouldbeusedinproduction
TC39releases

21.
-thereareproposalsthatreachedstage2,butwerewithdrawn
-onlystage3and4featuresshouldbeusedinproduction
TC39releases
ES2015 big bang

22.
-thereareproposalsthatreachedstage2,butwerewithdrawn
-onlystage3and4featuresshouldbeusedinproduction
TC39releases
ES2015 big bang
ES2016 small

23.
TC39releases
Array.prototype.includes(ES2016)
Champion:DomenicDenicola(Google)
https://tc39.github.io/Array.prototype.includes/

24.
TC39releases
Array.prototype.includes(ES2016)
Champion:DomenicDenicola(Google)
https://tc39.github.io/Array.prototype.includes/

25.
TC39releases
Asyncfunctions(ES2017)
Champion:BrianTerlson(Microsoft)
https://tc39.github.io/ecmascript-asyncawait/

26.
TC39releases
Asyncfunctions(ES2017)
Champion:BrianTerlson(Microsoft)
https://tc39.github.io/ecmascript-asyncawait/

27.
TC39releases-ES2018
Champion:JordanHarband(Airbnb)
https://tc39.github.io/proposal-promise-finally/
PromiseFinally(ES2018)

28.
TC39releases-ES2018
PromiseFinally(ES2018)
Champion:JordanHarband(Airbnb)
https://tc39.github.io/proposal-promise-finally/

29.
TC39releases-ES2018
ObjectRest/SpreadProperties(ES2018)
Champion:SebastianMarkbåge(Facebook)
https://tc39.github.io/proposal-object-rest-spread/

30.
TC39releases-ES2018
ObjectRest/SpreadProperties(ES2018)
Champion:SebastianMarkbåge(Facebook)
https://tc39.github.io/proposal-object-rest-spread/

31.
TC39releases-ES2018
AsynchronousIterators(ES2018)
Champion:DomenicDenicola(Google)
https://tc39.github.io/proposal-async-iteration/

32.
TC39releases-ES2018
AsynchronousIterators(ES2018)
Champion:DomenicDenicola(Google)
https://tc39.github.io/proposal-async-iteration/

33.
TC39releases-whatnext?
Function.prototype.toString(stage3)
global(stage3)
Array.prototype.{flatMap,flatten}(stage3)
NumericSeparators(stage3)
Optionalcatchbinding(stage3)
…
ES2019
likely

34.
proposals
https://github.com/tc39/proposals
finishedproposalsandreleasedate
https://github.com/tc39/proposals/blob/master/finished-proposals.md
TC39process
https://tc39.github.io/process-document/
TC39conformancetestsuite
https://github.com/tc39/test262
Book:ExploringES2018andES2019
http://exploringjs.com/es2018-es2019/
TC39Links

35.
TC39
theirprocess
and somefeatures