For AI agents: the complete documentation index is available at /tc39-atlas/en/llms.txt, the full documentation bundle is available at /tc39-atlas/en/llms-full.txt, and this page is available as Markdown at /tc39-atlas/en/proposals/index.md.
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  • Proposal index

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    Stage 4 · 96

    ProposalStatusECMAScript edition
    .at()FinishedES2022
    Accessible Object.prototype.hasOwnPropertyFinishedES2022
    Array find from lastFinishedES2023
    Array GroupingFinishedES2024
    Array.fromAsyncFinishedES2026
    Array.prototype.{flat,flatMap}FinishedES2019
    Array.prototype.includesFinishedES2016
    ArrayBuffer transferFinishedES2024
    Async functionsFinishedES2017
    Asynchronous IterationFinishedES2018
    Atomics.pauseFinishedES2027
    Atomics.waitAsyncFinishedES2024
    BigIntFinishedES2020
    Change Array by CopyFinishedES2023
    Class Fields (Private instance methods and accessors, Class Public Instance Fields & Private Instance Fields, Static class fields and private static methods)FinishedES2022
    Class Static BlockFinishedES2022
    DateTimeFormat dateStyle & timeStyleFinishedES2021
    Duplicate named capture groupsFinishedES2025
    Ergonomic brand checks for Private FieldsFinishedES2022
    Error CauseFinishedES2022
    Error.isErrorFinishedES2026
    Explicit Resource ManagementFinishedES2027
    Exponentiation operatorFinishedES2016
    Extend TimeZoneName Option ProposalFinishedES2022
    Float16 on TypedArrays, DataView, Math.f16roundFinishedES2025
    for-in mechanicsFinishedES2020
    Function.prototype.toString revisionFinishedES2019
    globalThisFinishedES2020
    Hashbang GrammarFinishedES2023
    Import AttributesFinishedES2025
    import.metaFinishedES2020
    import()FinishedES2020
    Intl Enumeration APIFinishedES2022
    Intl Era and MonthCode ProposalFinishedES2026
    Intl Locale InfoFinishedES2026
    Intl.DateFormat.prototype.formatRangeFinishedES2021
    Intl.DateTimeFormat.prototype.formatToPartsFinishedES2017
    Intl.DisplayNamesFinishedES2021
    Intl.DisplayNames v2FinishedES2022
    Intl.DurationFormatFinishedES2025
    Intl.ListFormatFinishedES2021
    Intl.LocaleFinishedES2020
    Intl.NumberFormat Unified API ProposalFinishedES2020
    Intl.NumberFormat V3FinishedES2023
    Intl.NumberFormat.prototype.formatToPartsFinishedES2018
    Intl.PluralRulesFinishedES2018
    Intl.RelativeTimeFormatFinishedES2020
    Intl.Segmenter: Unicode Segmentation in JavaScriptFinishedES2022
    Iterator SequencingFinishedES2026
    Joint IterationFinishedES2027
    JSON ModulesFinishedES2025
    JSON supersetFinishedES2019
    JSON.parse source text accessFinishedES2026
    Lifting template literal restrictionFinishedES2018
    Logical Assignment OperatorsFinishedES2021
    Math.sumPreciseFinishedES2026
    New Set methodsFinishedES2025
    Nullish coalescing OperatorFinishedES2020
    Numeric separatorsFinishedES2021
    Object.fromEntriesFinishedES2019
    Object.getOwnPropertyDescriptorsFinishedES2017
    Object.values/Object.entriesFinishedES2017
    Optional catch bindingFinishedES2019
    Optional ChainingFinishedES2020
    Promise.allSettledFinishedES2020
    Promise.anyFinishedES2021
    Promise.prototype.finallyFinishedES2018
    Promise.tryFinishedES2025
    Promise.withResolversFinishedES2024
    Redeclarable global eval-introduced varsFinishedES2025
    RegExp Lookbehind AssertionsFinishedES2018
    RegExp Match IndicesFinishedES2022
    RegExp ModifiersFinishedES2025
    RegExp named capture groupsFinishedES2018
    RegExp Unicode Property EscapesFinishedES2018
    RegExp v flag with set notation + properties of stringsFinishedES2024
    RegExp.escapeFinishedES2025
    Resizable and growable ArrayBuffersFinishedES2024
    Rest/Spread PropertiesFinishedES2018
    s (dotAll) flag for regular expressionsFinishedES2018
    Shared memory and atomicsFinishedES2017
    String paddingFinishedES2017
    String.prototype.{trimStart,trimEnd}FinishedES2019
    String.prototype.matchAllFinishedES2020
    String.prototype.replaceAllFinishedES2021
    Symbol.prototype.descriptionFinishedES2019
    Symbols as WeakMap keysFinishedES2023
    Sync Iterator helpersFinishedES2025
    TemporalFinishedES2027
    Top-level awaitFinishedES2022
    Trailing commas in function parameter lists and callsFinishedES2017
    Uint8Array to/from Base64FinishedES2026
    UpsertFinishedES2026
    WeakRefsFinishedES2021
    Well-formed JSON.stringifyFinishedES2019
    Well-Formed Unicode StringsFinishedES2024

    Stage 3 · 13

    Stage 2.7 · 6

    ProposalStatusECMAScript edition
    Decorator MetadataActive
    DecoratorsActive
    ESM Phase ImportsActive
    Immutable ArrayBuffersActive
    Import BytesActive
    ShadowRealmActive

    Stage 2 · 29

    Stage 1 · 110

    ProposalStatusECMAScript edition
    {BigInt,Number}.fromStringActive
    Alias AccessorsActive
    Array EqualityActive
    Array filteringActive
    Array.prototype.unique()Active
    Array.zip and Array.zipKeyedActive
    Asset ReferencesActive
    async do expressionsActive
    Async initializationActive
    await operationsActive
    Bigint from exponentialActive
    BigInt MathActive
    Binary ASTActive
    Block ParamsActive
    Built In Modules (aka JS Standard Library)Active
    Bulk-add array elementsActive
    Call-this operatorActive
    Cancellation APIActive
    Change Number.parseInt/parseFloat to not coerce null/undefined/NaN (repo link TBD)Active
    class Access ExpressionsActive
    Class Brand ChecksActive
    Class Method Parameter DecoratorsActive
    Collection methodsActive
    Compare Strings by CodepointActive
    ComparisonsActive
    CompartmentsActive
    Composable Accessors via built-in decoratorsActive
    CompositesActive
    Concurrency ControlActive
    Cryptographically Secure Random Number GenerationActive
    DataView get/set Uint8Clamped methodsActive
    DecimalActive
    Declarations in ConditionalsActive
    Deep Path Properties in Record LiteralsActive
    Disposable AsyncContext.VariableActive
    do expressionsActive
    Double-Ended Iterator and DestructuringActive
    Dynamic ModulesActive
    EmitterActive
    EnumsActive
    eraDisplay option for Intl.DateTimeFormatActive
    Error option framesAboveActive
    Error option limitActive
    Error stacksActive
    export all fromActive
    export v from "mod"; statementsActive
    ExtensionsActive
    Faster Promise adoptionActive
    First-class protocolsActive
    Freezing prototypesActive
    Function and Object Literal DecoratorsActive
    Function MemoizationActive
    Function onceActive
    Get IntrinsicActive
    Grouped Accessors and Auto-AccessorsActive
    IDL for ECMAScriptActive
    Improved Escapes for Template LiteralsActive
    InspectorActive
    Iterator uniqueActive
    Legacy reflection features for functions in JavaScriptActive
    Limited ArrayBufferActive
    Linear MatchingActive
    Locale ExtensionsActive
    Map get and deleteActive
    Mass Proxy RevocationActive
    Maximally minimal mixinsActive
    Module GlobalActive
    Module KeysActive
    Module sync assertActive
    Modulus and Additional Integer MathActive
    More Currency Display ChoicesActive
    More Random FunctionsActive
    Negated in and instanceof operatorsActive
    new.initializeActive
    Object pick/omitActive
    Object.freeze + Object.seal syntaxActive
    Object.propertyCountActive
    ObservableActive
    of and from on collection constructorsActive
    OOM Fails FastActive
    Optional chaining in assignment LHSActive
    Partial applicationActive
    Pattern MatchingActive
    Policy Maps and SetsActive
    Preserve Host VirtualizabilityActive
    Private declarationsActive
    Prototype pollution mitigationActive
    Readonly CollectionsActive
    RegExp \R EscapeActive
    RegExp Atomic OperatorsActive
    RegExp Extended Mode and CommentsActive
    Restrict subclassing support in built-in methodsActive
    Reverse iterationActive
    Reversible string splitActive
    Richer KeysActive
    SES (Secure EcmaScript)Active
    SignalsActive
    Slice notationActive
    StabilizeActive
    Standardized DebugActive
    Strict Enforcement of 'using'Active
    String.cookedActive
    String.prototype.codePointsActive
    Support for Distributed Promise PipeliningActive
    Type AnnotationsActive
    TypedArray ConcatActive
    TypedArray Find WithinActive
    uniform parsing of quasi-standard Date.parse inputActive
    Unordered Async Iterator HelpersActive
    Wavy Dot: Syntactic Support for Promise PipeliningActive

    Stage 0 · 16

    Unstaged · 57

    ProposalStatusECMAScript edition
    "use module"Inactive
    [Stable Formatting] stable-formattingActive
    {Set,Map}.prototype.toJSONInactive
    Annex B — HTML Attribute Event HandlersWithdrawn
    ArrayBuffer.prototype.transferWithdrawn
    BlöcksWithdrawn
    Builtins.typeOf() and Builtins.is()Withdrawn
    Callable class constructorsWithdrawn
    Cancelable PromisesWithdrawn
    Date.parse fallback semanticsInactive
    Default Behaviours for some Intl APIsActive
    deprecatedInactive
    Distinguishing literal stringsWithdrawn
    Dynamic Import Host AdjustmentWithdrawn
    Dynamic Module ReformWithdrawn
    explore associating a unit with a numberActive
    Extensible numeric literalsWithdrawn
    from ... importInactive
    Function helpersInactive
    Function.pipe and flowWithdrawn
    Generator arrow functionsWithdrawn
    Generic ComparisonWithdrawn
    Getting last element of ArrayWithdrawn
    Improving iteration on ObjectsWithdrawn
    Intl Energy UnitsActive
    Intl LocaleMatcherActive
    Intl Sequence UnitsActive
    Intl.DateTimeFormat Alignment With Other StandardsActive
    Intl.MessageFormatActive
    Intl.MessageResourceActive
    Intl.Segmenter v2Active
    Intl.ZonedDateTimeFormatActive
    isTemplateObjectWithdrawn
    JSON.tryParseInactive
    Math ExtensionsWithdrawn
    Math.signbit: IEEE-754 sign bitWithdrawn
    Normative ICU ReferenceWithdrawn
    Object enumerablesInactive
    Object.shallowEqualWithdrawn
    Operator overloadingWithdrawn
    Proposed Grammar change to ES ModulesInactive
    Record & TupleWithdrawn
    RefCollectionWithdrawn
    RegExp Atomic Groups & Possessive QuantifiersInactive
    Sequence properties in Unicode property escapesWithdrawn
    SIMD.JS - SIMD APIsInactive
    Smart Unit Preferences in Intl.NumberFormatActive
    String.prototype.atInactive
    Symbol.thenableWithdrawn
    Tagged Collection LiteralsWithdrawn
    Typed ObjectsInactive
    TypedArray stride parameterWithdrawn
    Unused Function ParametersInactive
    Updates to Tail Calls to include an explicit syntactic opt-inInactive
    UUIDWithdrawn
    WeakRefs cleanupSomeWithdrawn
    ZonesWithdrawn