---
# System prepended metadata

title: 78th meeting of TC39

---

# 78th meeting of TC39

- TCQ: https://tcq.app/meeting/BSXq
- Hallway track: https://hubs.mozilla.com/oAAvRHu/tc39
- Agenda: https://github.com/tc39/agendas/blob/master/2020/09.md
- Reflector: https://github.com/tc39/Reflector/issues/321

## Day 1 ([notes](https://mths.be/tc39day1))

<details>

<summary>10:00 to 15:00 JST (UTC +9) on September 21st, 2020</summary>

### 10:00-12:00
- Opening, welcome, housekeeping (Aki)
    - Introduce chairs, CoC, communication tools, IPR
    - Find volunteers for note taking
    - Next meeting date, time, logistics
    - Approval of the minutes from last meeting
    - Adoption of the agenda
- Secretary's Report (15m, Istvan Sebestyen)
- ECMA262 Status Updates (15m)
- ECMA402 Status Updates (15m)
- ECMA404 Status Updates (1m)
- Ecma TC53 Liaison Report (10m)
- Updates from the CoC Committee (15m)
- 15m · The last 5 years of Test262, a brief review · Leo Balter
- 10m · Explicitly specify order of operations in MakeTime · Kevin Gibbons
- 30m · Move \_\_proto__ out of annex B · Gus Caplan

### lunch (60 minutes)

### 13:00-15:00

- 15m · Align detached buffer semantics with web reality · Ross Kirsling
- 10m · Specify order of name and length for built-in functions · Kevin Gibbons
- 15m · Arbitrary Strings as export/import names · Bradley Farias
- 30m · Numeric literal suffixes update: separate namespace version  · Daniel Ehrenberg
- 5m · need another stage 3 reviewer for iterator helpers · Michael Ficarra
- 5m · 🕘 Withdrawing TypedArray stride · Shu-yu Guo
- 15m · F.p.bind with infinite-length functions · Kevin Gibbons
- 15m · Date arithmetic · Kevin Gibbons
- 10m · Move outreach groups to the TC39 org, like incubator calls? Daniel Ehrenberg

</details>

## Day 2 ([notes](https://mths.be/tc39day2))

<details>

<summary>10:00 to 15:00 JST (UTC +9) on September 22nd, 2020</summary>

### 10:00-12:00

- 20m · Intl.DisplayNames for Stage 4 Frank Yung-Fong Tang
- 15m · .item() for Stage 3  · Tab Atkins, Shu-yu Guo
- 30m · Import Assertions for Stage 3 · Sven Sauleau, Daniel Ehrenberg, Myles Borins, Dan Clark, Shu-yu Guo
- 30m · JSON Modules update · Sven Sauleau, Daniel Ehrenberg, Myles Borins, Dan Clark, Shu-yu Guo
- 10m · GetOption in ECMA-262 · Philip Chimento

### lunch (60 minutes)

### 13:00-15:00

- 30m · Intl Enumeration API for stage 2 · Frank Yung-Fong Tang
- 30m · Record & Tuple Stage 2 update · Rick Button
- 30m · Class static initialization block for Stage 2 · Ron Buckton
- 25m · Process document clarifications · Yulia Startsev
- 30m · Class Access Expressions for Stage 2 · Ron Buckton

</details>

## Day 3 ([notes](https://mths.be/tc39day3))

<details>

<summary>10:00 to 15:00 JST (UTC +9) on September 23rd, 2020</summary>

### 10:00-12:00

- 10m · Status update for class fields, private methods, static class features (editorial: unified specification) · Ujjwal
- 45m · Ergonomic brand checks for private fields for stage 3 · Jordan Harband
- 60m · Decorators: A new proposal iteration · Chris Garrett and Daniel Ehrenberg

### lunch (60 minutes)

### 13:00-15:00

- 30m · String.dedent for stage 1 · Hemanth HM
- 30m · Temporal Stage 2 update  · Ujjwal Sharma
- 30m · Intl.DisplayNames V2 for stage 1 · Frank Yung-Fong Tang
- 30m · Intl Locale Info for stage 1 · Frank Yung-Fong Tang
- 20m · Conformance for enumerable options in 262 and 402 · Shane F. Carr

</details>

## Day 4 ([notes](https://mths.be/tc39day4))

<details open>

<summary>10:00 to 15:00 JST (UTC +9) on September 24th, 2020</summary>

### 10:00-12:00

- 5m · Revisit Ergonomic Brand Checks for Private Fields · Jordan Harband
- 60m · Resizable and growable ArrayBuffers for Stage 2 · Shu-yu Guo
- 60m · Builtin Modules for Stage 2 · Michael Saboff

### lunch (60 minutes)

### 13:00-15:00

- 15m · Error Cause for Stage 1 · Chengzhong Wu
- 15m · Double-Ended Iterator and Destructuring for Stage 1 · HE Shi-Jun
- 30m · Standardized Debug for Stage 1 · Gus Caplan
- 20m · Unused Function Parameters for stage 1 · Gus Caplan
- 30m · Modulus and Additional Integer Math for Stage 1 · Peter Hoddie
- Incubation call chartering (15m on the last day)

</details>

***

## Overflow

### From agenda

- 45m · Extensions for Stage 1 · HE Shi-Jun
- 20m · 🕘 Mechanisms to lighten the load on note-takers · Philip Chimento, Daniel Ehrenberg and Mark Miller
- 20m · 🕘 Supporting MDN's documentation about in TC39's output · Daniel Ehrenberg
- 15m ·  Test262 Status Updates (Rick Waldron)

### Timebox overrun

- ~~5 min · extended numeric literals · Daniel Ehrenberg~~
- 5 min · Revisit Ergonomic Brand Checks for Private Fields · Jordan Harband

## Schedule constraints

- Yulia Startsev will only be available in the afternoon sessions (1pm-3pm local time).
- Frank Yung-Fong Tang will only be available in the 2nd-4th day (September 22nd - 24th JST).
- Ujjwal Sharma will not be available on the 22nd (second day).
- Temporal should go on Day 3 or 4.



<style>summary h2 { display: inline; }</style>