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ECMAScript proposals

ECMAScript Internationalization API Specification proposals

Contributing new proposals

Please see Contributing to ECMAScript for the most up-to-date information on contributing proposals to this standard.

Active proposals

Proposals follow this process document. This list contains only stage 2 proposals and higher that have not yet been withdrawn/rejected, or become finished. Stage 2 indicates that the committee expects these features to be developed and eventually included in the standard.

Stage 3

Proposal Author Champion Test262 Feature Flag Last Presented
Legacy RegExp features in JavaScript Claude Pache Mark Miller
Claude Pache
legacy-regexp May 2017
JSON Modules Myles Borins
Sven Sauleau
Dan Clark
Daniel Ehrenberg
Myles Borins
Sven Sauleau
Dan Clark
Daniel Ehrenberg
json-modules January 2021
Temporal Philipp Dunkel
Maggie Johnson-Pint
Matt Johnson-Pint
Brian Terlson
Shane Carr
Ujjwal Sharma
Philip Chimento
Jason Williams
Justin Grant
Philipp Dunkel
Maggie Johnson-Pint
Matt Johnson-Pint
Brian Terlson
Shane Carr
Ujjwal Sharma
Philip Chimento
Jason Williams
Justin Grant
Temporal March 2021
Decorators Daniel Ehrenberg
Kristen Hewell Garrett
Kristen Hewell Garrett decorators March 2023
JSON.parse source text access Richard Gibson Richard Gibson json-parse-with-source January 2023
RegExp Modifiers Ron Buckton Ron Buckton regexp-modifiers June 2022
Duplicate named capture groups Kevin Gibbons Kevin Gibbons regexp-duplicate-named-groups July 2022
Array.fromAsync J.S. Choi J.S. Choi Array.fromAsync May 2023
New Set methods Michał Wadas
Sathya Gunasekaran
Kevin Gibbons
Kevin Gibbons set-methods November 2022
Sync Iterator helpers Gus Caplan Michael Ficarra
Jonathan Keslin
Kevin Gibbons
iterator-helpers November 2022
Explicit Resource Management Ron Buckton Ron Buckton explicit-resource-management March 2023
Float16 on TypedArrays, DataView, Math.f16round Leo Balter Leo Balter
Kevin Gibbons
May 2023
Decorator Metadata Kristen Hewell Garrett Kristen Hewell Garrett May 2023
Import Attributes Myles Borins
Sven Sauleau
Dan Clark
Daniel Ehrenberg
Sven Sauleau
Dan Clark
Daniel Ehrenberg
Nicolò Ribaudo
import-attributes March 2023
Source Phase Imports Luca Casonato Guy Bedford
Luca Casonato
July 2023
Uint8Array to/from Base64 Kevin Gibbons Kevin Gibbons February 2024

Stage 2.7

Proposal Author Champion Test262 Feature Flag Last Presented
ShadowRealm Caridy Patiño
Jean-Francois Paradis
Dave Herman
Mark Miller
Caridy Patiño
Leo Balter
Rick Waldron
Chengzhong Wu
ShadowRealm February 2024

Stage 2

Proposal Author Champion Last Presented
function.sent metaproperty Allen Wirfs-Brock HE Shi-Jun July 2019
throw expressions Ron Buckton Ron Buckton January 2018
Function implementation hiding Domenic Denicola
Michael Ficarra
Michael Ficarra June 2020
collection normalization Bradley Farias Bradley Farias January 2019
Array.isTemplateObject Mike Samuel, Krzysztof Kotowicz Krzysztof Kotowicz December 2019
Map.prototype.emplace Bradley Farias Erica Pramer July 2020
Dynamic Import Host Adjustment Mike Samuel, Krzysztof Kotowicz Krzysztof Kotowicz December 2019
Record & Tuple Robin Ricard
Richard Button
Robin Ricard
Richard Button
December 2021
Module Expressions Surma
Daniel Ehrenberg
Nicolò Ribaudo
Surma
Nicolò Ribaudo
November 2022
Pipeline Operator J. S. Choi
James DiGioia
Ron Buckton
Tab Atkins
J. S. Choi
Ron Buckton
Tab Atkins
August 2021
Destructure Private Fields Justin Ridgewell Justin Ridgewell December 2021
RegExp Buffer Boundaries (\A, \z, \Z) Ron Buckton Ron Buckton December 2021
String.dedent Misha Kaletsky
Hemanth HM
Justin Ridgewell
Hemanth HM
Justin Ridgewell
June 2022
JSON.parseImmutable Robin Ricard
Richard Button
Nicolò Ribaudo
Ashley Claymore
Robin Ricard
Richard Button
Nicolò Ribaudo
Ashley Claymore
July 2022
Module Declarations Daniel Ehrenberg
Nicolò Ribaudo
Daniel Ehrenberg
Mark Miller
Nicolò Ribaudo
November 2022
Symbol Predicates Robin Ricard
Jordan Harband
Ashley Claymore
Jordan Harband
January 2023
Async Iterator helpers Gus Caplan Michael Ficarra
Jonathan Keslin
Kevin Gibbons
January 2023
Iterator.range Jack Works Jack Works March 2023
Async Context Chengzhong Wu Chengzhong Wu
Justin Ridgewell
March 2023
Time Zone Canonicalization Justin Grant Justin Grant
Richard Gibson
May 2023
Deferring Module Evaluation Yulia Startsev
Guy Bedford
Yulia Startsev
Guy Bedford
Nicolò Ribaudo
July 2023
RegExp.escape Domenic Denicola
Benjamin Gruenbaum
Jordan Harband
Jordan Harband September 2023
Joint Iteration Michael Ficarra Michael Ficarra February 2024
Promise.try Jordan Harband Jordan Harband February 2024
Redeclarable global eval-introduced vars Shu-yu Guo Shu-yu Guo February 2024

The test262 feature flag links to a code search of tests using that feature flag, which may constitute complete or partial coverage. The ❓ means there is no feature flag for tests yet.

Onboarding existing proposals

Proposals that are Stage 1 and above must be transferred to the TC39 GitHub organization for discoverability and archival purposes. To onboard a proposal that lives outside the TC39 organization:

  1. Transfer your repository to the @tc39-transfer organization
  • if you are a TC39 delegate, but not a member of that organization, please contact @LJHarb
  1. The Github Administrator, or One of the chairs, will transfer your repository to the TC39 organization the next chance they get.

Note that as part of the onboarding process your repository name may be normalized. Don't worry, repo redirects will continue to work as long as you never create a fork, or a new repository, with the same name - although Github Pages redirects will be broken (please update your links!).