This is a talk about TC39, their process, maturity stages and some of the latest ECMAScript features. This talk was presented at TDC2018 - Floripa.

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