# 105^th^ Meeting of TC39

- TCQ: https://tcq.app/meeting/RKti
- Agenda: https://github.com/tc39/agendas/blob/main/2024/12.md
- Reflector: https://github.com/tc39/Reflector/issues/545

## Agenda key

When applicable, use these emoji as a prefix to the agenda item topic.

| Emoji | Meaning |
| :---: | :--- |
| ❄️ | hard schedule constraints apply to this agenda item (e.g. presenter) |
| 🔒 | schedule constraints apply to this agenda item |
| ⌛️ | late addition for stage advancement and/or schedule prioritization |
| 🔁 | continuation of a previous agenda item |

## Day 1 ([notes](https://docs.google.com/document/d/1dkyaGEwG_GXHRhG7LivWVMIGJlHS5S_uieGEmHqFvNE/edit))

<details>

<summary>10:00 to 15:00 MST (America/Denver) on Monday</summary>

### 10:00-12:00 (full)

- Opening & Welcome (15m, Rob Palmer)
- Opening of the meeting
- TC39 follows its Code of Conduct
- Overview of communication tools
- Quick recap of meeting IPR policy
- Reminder to review Github Delegate teams (Jordan Harband)
- <details>
<summary>Note about meeting transcriptions</summary>
A detailed transcript of the meeting is being prepared and will be eventually posted on GitHub. You may edit this at any time during the meeting in Google Docs for accuracy, including deleting comments which you do not wish to appear. You may also request corrections or deletions after the fact, by editing the Google Doc (in the first two weeks after the TC39 meeting) or subsequently making a PR in the notes repository or contacting the TC39 chairs.
</details>
- 🗒️ Call for note-takers
- Adoption of the agenda
- Approval of the minutes from last meeting
- Next meeting host and logistics
- Secretary's Report ([slides](TBD)) (15m, Samina Husain)
- Project Editors’ Reports
- [ECMA262](https://github.com/tc39/ecma262) Status Updates ([slides](https://docs.google.com/presentation/d/1IS6hsFker8TM_mPtK1VQbFCH2TK3LljOxFu6-zMCjkM/edit)) (15m, Shu-yu Guo)
- [ECMA404](https://www.ecma-international.org/publications/standards/Ecma-404.htm) Status Updates (1m, Chip Morningstar)
- [Test262](https://github.com/tc39/test262) Status Updates (15m, Philip Chimento)
- Task Group Reports
- TG3: Security (5m, Chris de Almeida)
- TG4: Source Maps (5m, Jonathan Kuperman)
- TG5: Experiments in Programming Language Standardization (5m, Mikhail Barash)
- Updates from the [CoC Committee](https://tc39.es/code-of-conduct/#code-of-conduct-committee) (1m, Chris de Almeida)
- Call for reviewers - [ESM Phase Imports](https://github.com/tc39/proposal-esm-phase-imports) (1m, Guy Bedford)
- Process document fixes and corrections: [#46](https://github.com/tc39/process-document/pull/46) and [#48](https://github.com/tc39/process-document/pull/48) (5m, Chris de Almeida)
- [More Currency Display Choices](https://github.com/eemeli/proposal-intl-currency-display-choices) for Stage 1/2 (30m, Eemeli Aro)
- [Upsert (formerly Map.emplace)](https://github.com/tc39/proposal-upsert) Update and request for Stage 2 reviewers ([Slides](https://docs.google.com/presentation/d/15sWTvdWIo9Jt12LFRNBPJo1N_8xsMSCB3jy73HBFX-M/)) (30m, Daniel Minor)
- [Intl.DurationFormat](https://github.com/tc39/proposal-intl-duration-format) for Stage 4. ([PR](https://github.com/tc39/ecma402/pull/943)) ([slides](https://docs.google.com/presentation/d/1bAuZ0ZSSYUdJxiDYXz2tUWHZwaOmYkNoLpQBBy_qz1w/edit?usp=sharing)) (15m, Ujjwal Sharma)
- [`Error.isError`](https://github.com/tc39/proposal-is-error/issues/7) to stage 3? (15m, Jordan Harband)
- [iterator helpers close receiver on argument validation failure](https://github.com/tc39/ecma262/pull/3467) (10m, Kevin Gibbons)
- [AsyncContext](https://github.com/tc39/proposal-async-context) request for Stage 2.7 reviewers (5m, Andreu Botella)

### Lunch (60 minutes)

### 13:00-15:00 (5m underflow)

- The importance of supporting materials ([slides](https://docs.google.com/presentation/d/1teo8pAE4lbFTIlPZxum2MBcNZfGdUM2Y8huEiVdvQiQ/)) (10m, Daniel Minor)
- 🔒 re-using IteratorResult objects in iterator helpers ([PR](https://github.com/tc39/ecma262/pull/3489)) ([slides](https://docs.google.com/presentation/d/1HQzC15dFnQClnUWYHSFx95aMuiJjHAjE186flPW7iZE)) (30m, Michael Ficarra)
- ❄️ [iterator sequencing](https://github.com/tc39/proposal-iterator-sequencing) for Stage 3 ([tests](https://github.com/tc39/test262/pull/4326)) ([slides](https://docs.google.com/presentation/d/1EHMDcnV9zJ1E7BRhKmYtzHchZvOzjWynR3W-VdNxglw)) (15m, Michael Ficarra)
- 🔒 [ShadowRealm](https://github.com/tc39/proposal-shadowrealm) for Stage 3 ([slides](https://ptomato.name/talks/tc39-2024-12)) (60m, Philip Chimento)

</details>

## Day 2 ([notes](https://docs.google.com/document/d/1GwqVW6kCBYJuBb_E-u-kx2UEPFktQi5Xic6pem88ZqE/edit?tab=t.0#heading=h.727dtucjdazf))

<details>

<summary>10:00 to 15:00 MST (America/Denver) on Tuesday</summary>

### 10:00-12:00 (full)

- 🔒 Briefing on the formation and goals of TC55 (or, All About Moving the WinterCG into Ecma) (30m, James M Snell) [slides](https://docs.google.com/presentation/d/1WnqF7y52QlPRw737ZOTC4rdmJ65-nT9BbOD05jr2sjE/edit?usp=sharing)
- ❄️ [Stabilize](https://github.com/Agoric/proposal-stabilize) to stage 1 ([youtube talk](https://www.youtube.com/watch?v=VHr4Jvvt0vc), [slides.key](https://github.com/Agoric/proposal-stabilize/raw/refs/heads/main/stabilize-talks/stabilize-stage1.key), [slides.pdf](https://github.com/Agoric/proposal-stabilize/blob/main/stabilize-talks/stabilize-stage1.pdf), [docs slides](https://docs.google.com/presentation/d/1474EreKln5bErl-pMUUq2PnX5LRo2Z93jxxGBNbZmco/edit?usp=sharing)) (60m, Mark Miller)
- 🔒 Module Harmony: where we are ([slides](https://docs.google.com/presentation/d/1V2-4Hj-HBVQwdphcJUsrbmbitOPBMSf3HhKSvhBk4d0/edit?usp=sharing)) (30m, Nicolò Ribaudo)
- [ECMA402](https://github.com/tc39/ecma402) Status Updates ([slides](https://hackmd.io/@ryzokuken/r1qXw2hQkx#/)) (5m, Ujjwal Sharma)

### Lunch (60 minutes)

### 13:00-15:00 (10m overflow)

- ❄️ [Immutable ArrayBuffer](https://github.com/tc39/proposal-immutable-arraybuffer) to stage 2 ([slides.key](https://github.com/tc39/proposal-immutable-arraybuffer/raw/refs/heads/main/immu-arraybuffer-talks/immu-arrayBuffers-stage2.key), [slides.pdf](https://github.com/tc39/proposal-immutable-arraybuffer/blob/main/immu-arraybuffer-talks/immu-arrayBuffers-stage2.pdf), [docs slides](https://docs.google.com/presentation/d/1S1ixC7AVg3s_p4ZNhu3zBMcIcKbFkmp6umnsQUKOIqw/edit?usp=sharing)) (30m, Mark Miller)
- 🔒 [`import defer`](https://github.com/tc39/proposal-defer-import-eval/) updates ([slides](https://docs.google.com/presentation/d/1yFbqn6px5rIwAVjBbXgrYgql1L90tKPTWZq2A5D6f5Q/)) (40m, Nicolò Ribaudo)
- 🔒 [Error Stacks Structure](https://github.com/tc39/proposal-error-stacks) for Stage 2 (60m, Jordan Harband)

</details>

## Day 3 ([notes](https://docs.google.com/document/d/1Y-1vgEHKj_19jTB_sxFoZf1na-OHIthH5LNixoeXxXA/edit?tab=t.0#heading=h.727dtucjdazf))

<details>

<summary>10:00 to 15:00 MST (America/Denver) on Wednesday</summary>

### 10:00-12:00 (full)

- ❄️🔒 [Import Sync](https://github.com/guybedford/proposal-import-sync) discussion, request for Stage 1? ([slides](https://docs.google.com/presentation/d/1GW_OCoVjd6OJi9BKSlQzQKqxrB0GUKHKFof4s3rn9yk/edit?usp=sharing)) (30m, Guy Bedford)
- ❄️🔒 [ESM Phase Imports](https://github.com/tc39/proposal-esm-phase-imports) for Stage 2.7 ([slides](https://docs.google.com/presentation/d/1qfnmqPkpuAqTv-1pll1Y6EkEHElf_58BtNBQSw9dpq8/edit?usp=sharing)) (90m, Guy Bedford)

### Lunch (60 minutes)

### 13:00-15:00 (2h underflow)

</details>

## Day 4 ([notes](https://docs.google.com/document/d/1I03plYy0fVsfBPmPOOcgW7IdbHBFhZk6EwkizmiVBEg/edit?tab=t.0))

<details open>

<summary>10:00 to 15:00 MST (America/Denver) on Thursday</summary>

### 10:00-12:00 (15m overflow)

- ❄️ Vision for numeric types in ECMAScript ([slides](https://docs.google.com/presentation/d/1Uzrf-IwPrljF2BhCbCWuwQxlgGSm_bcd3FRbPO3Yrio/edit#slide=id.p)) (60m, Shane F. Carr)
- Measure Stage 1 update (30m, Eemeli Aro)
- 🔁 Continuation: [Error Stacks Structure](https://github.com/tc39/proposal-error-stacks) for Stage 2 (30m, Jordan Harband)
- 🔁 Continuation: [`import defer`](https://github.com/tc39/proposal-defer-import-eval/) updates ([slides](https://docs.google.com/presentation/d/1yFbqn6px5rIwAVjBbXgrYgql1L90tKPTWZq2A5D6f5Q/)) (15m, Nicolò Ribaudo)

### Lunch (60 minutes)

### 13:00-15:00 (2h underflow)

</details>

***

## Overflow

### From agenda

### Timebox overrun

## Schedule constraints

### Normal Constraints

- Mark Miller: Monday 2 December will be hard for me to attend (due to travel). So at least my presentations will need to be elsewhen. I will be at all of the other days. :heavy_check_mark:
- Would be good for my "Stabilize" to precede Nicolò's "import defer". (Already briefly discussed with Nicolo) :heavy_check_mark:
- In decreasing priority order, I would like to be able to attend, so prefer any day other than Monday:
- Module Harmony
- Error Stack Structure
- ShadowRealm
- import defer
- re-using Iterator Result objects
- ESM Phase Sync
- TC55 (moving WinterCG)
- MF: the IteratorResult needs-consensus PR should be discussed before (though not necessarily immediately before) iterator sequencing Stage 3 advancement :heavy_check_mark:
- Guy Bedford is unavailable the morning of December 3.
- Shane Carr has personal family vacation on December 2-4 and would therefore prefer to present Vision for Numeric Types on December 5. :heavy_check_mark:
- Matthew Gaudet would like to attend Error Stacks; 1-3pm is the best range for the duration of the meeting. :heavy_check_mark:
- The Measure Stage 1 Update should be discussed after (though not necessarily immediately after) the Vision for numeric types in ECMAScript. :heavy_check_mark:

### Late-breaking Schedule Constraints

- Not super imortant, but if there is a choice it'd be great to have the "Module harmony" presentation before the other module presentations, as it gives a very high level overview.

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