Stabilize by-value [T; N] iterator core::array::IntoIter

[SimonSapin]

Tracking issue: #65798

This is unblocked now that min_const_generics has been stabilized in #79135.

This PR does not include the corresponding IntoIterator impl, which is #65819. Instead, an iterator can be constructed through the new method.

new would become unnecessary when IntoIterator is implemented and might be deprecated then, although it will stay stable.

[rust-highfive]

r? @cramertj

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[SimonSapin]

Stabilizing this iterator type with a new constructor that might be deprecated when IntoIterator is implemented later.

@rfcbot fcp merge

[SimonSapin]

Ah I forgot I need to be in the checkboxy list to propose FCP. @rust-lang/libs please start the process for:

Stabilizing this iterator type with a new constructor that might be deprecated when IntoIterator is implemented later.

[m-ou-se]

@rfcbot fcp merge

[rfcbot]

Team member @m-ou-se has proposed to merge this. The next step is review by the rest of the tagged team members:

• @Amanieu
• @BurntSushi
• @KodrAus
• @dtolnay
• @m-ou-se
• @sfackler
• @withoutboats

No concerns currently listed.

Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.

[rfcbot]

🔔 This is now entering its final comment period, as per the review above. 🔔

[SoniEx2]

Instead of having ::new, why not propose From for all stdlib iterators?

[SimonSapin]

@SoniEx2 I’m not sure what impls you have in mind, could you spell them out?

[SoniEx2]

Instead of having an IntoIter::new(...), have an IntoIter::from(...) powered by trait From.

This would be undeprecatable but it feels less silly and could be extended to the other iterators. Then you'd just use .into() and impl Iterator<Item=...>.

// example usage
BTreeMap::<&'static str, &'static str>::from_iter([("a", "b")].into())

[SimonSapin]

There’s no need to find another general pattern to turn collections into iterators, that’s the IntoIterator trait

[SoniEx2]

alternatively: [("a", "b")].into(): impl Iterator<Item=(&'static str, &'static str)>.collect::<BTreeMap<_, _>>()

the point is you'd use IntoIter::from() / [T; N].into() instead of [T; N].into_iter().

[rust-log-analyzer]

The job x86_64-gnu-llvm-9 failed! Check out the build log: (web) (plain)

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Successfully built ef9d50b97d38
Successfully tagged rust-ci:latest
Built container sha256:ef9d50b97d388e6ba90f8388b0997d746b3b0aae438d65cbb1bfb909e713d215
Uploading finished image to https://ci-caches.rust-lang.org/docker/1d8776fc6611839c0fe1104032e04cb412cf84a696fcac0418b82e4341b3688a883196f99e2f55a0df0b3c67d154c62dd0c4630956d70292523c69687b63cce6
upload failed: - to s3://rust-lang-ci-sccache2/docker/1d8776fc6611839c0fe1104032e04cb412cf84a696fcac0418b82e4341b3688a883196f99e2f55a0df0b3c67d154c62dd0c4630956d70292523c69687b63cce6 Unable to locate credentials
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[rfcbot]

The final comment period, with a disposition to merge, as per the review above, is now complete.

As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed.

The RFC will be merged soon.

[m-ou-se]

@bors r+ rollup

[bors]

📌 Commit 83d32b0 has been approved by m-ou-se