---
# System prepended metadata

title: Libs Meeting 2020-11-25
tags: [Minutes, Libs Meetings]

---

# Libs Meeting 2020-11-25

###### tags: `Libs Meetings` `Minutes`

## Agenda

- Triage
- Anything else?

## Triage

**FCPs**

Open FCPs: https://rfcbot.rs/ ([Amanieu](https://rfcbot.rs/fcp/Amanieu), [BurntSushi](https://rfcbot.rs/fcp/BurntSushi), [dtolnay](https://rfcbot.rs/fcp/dtolnay), [KodrAus](https://rfcbot.rs/fcp/KodrAus), [m-ou-se](https://rfcbot.rs/fcp/m-ou-se), [sfackler](https://rfcbot.rs/fcp/sfackler), [withoutboats](https://rfcbot.rs/fcp/withoutboats))
- [10 `rust-lang/rust` FCPs](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AT-libs+label%3Aproposed-final-comment-period) - One to discuss now.
  - Open concerns/problems:
    - [[77853](https://github.com/rust-lang/rust/pull/77853#issuecomment-709644325)] *slice::strip_{prefix,suffix}* - Conflicts with [rfc 2500](https://github.com/rust-lang/rfcs/blob/master/text/2500-needle.md).
    - <font color=#999>[[76505](https://github.com/rust-lang/rust/pull/76505)] *partition_in_place* - Discussed last meeting, but we still need to reply.</font>
    - <font color=#999>[[74304](https://github.com/rust-lang/rust/pull/74304)] *Wake trait* - Discussed last meeting. Need to ping BurntSushi.</font>
  - No open concerns (probably no discussion required in meeting):
    - <font color=#999>[[79213](https://github.com/rust-lang/rust/pull/79213#issuecomment-730632811)] *`core::slice::fill`*</font>
    - <font color=#999>[[79134](https://github.com/rust-lang/rust/pull/79134#issuecomment-731632271)] *division by NonZeroU*`*</font>
    - <font color=#999>[[79022](https://github.com/rust-lang/rust/pull/79022#issuecomment-726890403)] *deque_range*</font>
    - <font color=#999>[[77858](https://github.com/rust-lang/rust/pull/77858)] *split_inclusive*</font>
    - <font color=#999>[[74699](https://github.com/rust-lang/rust/pull/74699)] *`-1` as niche for file descriptors* - Started FCP in last meeting.</font>
    - <font color=#999>[[78083](https://github.com/rust-lang/rust/pull/78083)] *Entry::or_insert_with_key*</font>
  - Inactionable:
    - <font color=#999>[[70904](https://github.com/rust-lang/rust/pull/70904)] *seek_convenience* - Discussed last meeting, waiting for response from author.</font>
- [5 `rust-lang/rfcs` FCPs](https://github.com/rust-lang/rfcs/pulls?q=is%3Aopen+label%3AT-libs+label%3Aproposed-final-comment-period) - None to discuss now.
  - No open concerns (probably no discussion required in meeting):
    - <font color=#999>[[3007](https://github.com/rust-lang/rfcs/pull/3007)] *make core and std's panic identical*</font>
  - FCP to close:
    - <font color=#999>[[2944](https://github.com/rust-lang/rfcs/pull/2944)] *Freeze trait*</font>
    - <font color=#999>[[2708](https://github.com/rust-lang/rfcs/pull/2708)] *generic pointer to field*</font>
  - Ongoing discussion on the PR:
    - <font color=#999>[[2580](https://github.com/rust-lang/rfcs/pull/2580)] *pointer metadata & vtable*</font>
    - <font color=#999>[[2859](https://github.com/rust-lang/rfcs/pull/2859)] *secret types*</font>

**Nominated**

- [2 `rust-lang/rfcs` items](https://github.com/rust-lang/rfcs/issues?q=is%3Aopen+label%3AT-libs+label%3AI-nominated)
  - [[2979](https://github.com/rust-lang/rfcs/pull/2979)] *Libs Governance*
    Did we want to make some time to look at this in more detail?
  - <font color=#999>[[2477](https://github.com/rust-lang/rfcs/pull/2477)] *[]::group_by[_mut]* - Discussed last meeting, but we still need to reply. (Keep in mind an implementation PR was previously closed in favor of an RFC, but not necessary)</font>
- [19 `rust-lang/rust` items](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AT-libs+label%3AI-nominated)
  - <font color=#999>[[78634](https://github.com/rust-lang/rust/pull/78634)] *proc_macro::Ident == strings* - Discussed last meeting, but we still need to reply.</font>
  - [[63171](https://github.com/rust-lang/rust/issues/63171)] *f32 formatting*
    Not only digits *after* the decimal point get truncated to the shortest possible representation.
    The digits *before* the decimal point get truncated and then padded with zeros, leading to confusiong results.
    Should we only truncate if it makes the representation shorter?
    E.g. `0.3` instead of `0.30000001...`, but not `123456790000000000` instead of `123456790519087104`.
  - For many of these I'm not sure why they were nominated.
    - Removed `I-nominated` from tracking issues with no discussion where an stabilization PR was started.
    - Many of these can probably go for a stabilization PR. We should let the submitter know that's an option.

**Waiting on team**

- [12 `rust-lang/rust` items](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AT-libs+label%3AS-waiting-on-team)
  - [[75065](https://github.com/rust-lang/rust/pull/75065)] *Format Duration with "us" instead of "μs"*
- [0 `rust-lang/rfcs` items](https://github.com/rust-lang/rfcs/issues?q=is%3Aopen+label%3AT-libs+label%3AS-waiting-on-team)

**Needs decision**

- [`rust-lang/rust` items](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AT-libs+label%3AI-needs-decision)
  - (13 open)

## Notes

- 77853: Add a dummy generic signature so we're less likely to break the shape of the method in the future and stabilize. 
  - [x] **Replied.**
- 63171: We do strange things with floating point rendering. Do want to try fix this? We're happy to try and fix this up. 
  - [x] **Replied.**
- 65798: There's not much left blocking this. Submit a PR with an `IntoIterator` impl on `[T; N]`, possibly consider stabilizing `array::IntoIter::new`.
  - [x] **Replied.**
- 75065: We need to reply to this somehow. It will probably stay the status-quo. If we want to fix this _somehow_ it should be broader than this specific case.
  - [x] **Replied.**
- 37984: We can't really do this even if we want to.
  - [x] **Replied.**
- 2848 (rfc): Ideally, we don't want `Range` to implement `Iterator`, and we do want it to implement `Copy`. We could consider implementing a `ops2` module with "fixed" `Range` in it.
  - [x] **Replied.**
- Make an overview of what we're doing for 2021 so we can actually clearly communicate it. Do we want a way for libraries to have some visibility to switch on editions? `#[cfg(edition = "2021")]`.
  - [x] **Done.**

## Actions

- [x] Reply to all issues/PRs discussed in the [last meeting](https://hackmd.io/6p19j-6sRGu5mAInWOv_Ag?view#Notes).
- [ ] Reply to all issues/PRs discussed in this meeting.
- [x] Go through [`I-nominated` issues](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AT-libs+label%3AI-nominated):
  - Many of these can probably go for a stabilization PR. We should let the submitter know that's an option.
