Exclusive nits

[ghost]

Tracking issue: #98407

• const fns now have rustc_const_unstable
• Added Generator forwarding impl
• Added FnOnce & FnMut forwarding impls
• Made the From impl unstably const

[rustbot]

r? @joshtriplett

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[rustbot]

Hey! It looks like you've submitted a new PR for the library teams!

If this PR contains changes to any rust-lang/rust public library APIs then please comment with @rustbot label +T-libs-api -T-libs to tag it appropriately. If this PR contains changes to any unstable APIs please edit the PR description to add a link to the relevant API Change Proposal or create one if you haven't already. If you're unsure where your change falls no worries, just leave it as is and the reviewer will take a look and make a decision to forward on if necessary.

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[ghost]

@rustbot label +T-libs-api -T-libs

[bors]

☔ The latest upstream changes (presumably #102795) made this pull request unmergeable. Please resolve the merge conflicts.

[anden3]

Hello @h4x5! I noticed that there are some merge conflicts for this PR, what's the status of it?

[ghost]

@anden3 I can resolve the conflicts if a reviewer is interested in merging this

[anden3]

@h4x5 I believe one of the preconditions for getting a review is to not have merge conflicts, so it's probably much easier if you fix those first.

[Dylan-DPC]

@h4x5

I can resolve the conflicts if a reviewer is interested in merging this

it would be easier to resolve the conflicts, and then wait for the reviewer to review it when they have the time to.

[bjorn3]

Made the From impl unstably const

#110393 removed all const impls to make it easier to change the way const traits work. Please don't add new const impls for now.

[JohnCSimon]

@h4x5
ping from triage - can you post your status on this PR? There hasn't been an update in a few months. Thanks!

FYI: when a PR is ready for review, send a message containing
@rustbot ready to switch to S-waiting-on-review so the PR is in the reviewer's backlog.

---

[dtolnay]

Per #104057 (comment), I don't think the impl<T> const From<T> for Exclusive<T> is something we would accept for now.

The rest of the PR looks good to me.

[dtolnay]

I have extracted the FnOnce, FnMut, Generator part of this PR to #116241.