Implement From<&'a &'static str> for Arguments<'a>

[EFanZh]

Provides a way to construct an Arguments object from an &'static str object, and calling as_str on the result object will return Some(&'static str).

ACP: rust-lang/lib-team#257.

[rustbot]

r? @joshtriplett

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[dtolnay]

Thanks for the PR!

Based on rust-lang/libs-team#257 (comment), I believe this is currently blocked while we work to figure out whether #115129 is going to be landable.

[bors]

☔ The latest upstream changes (presumably #125443) made this pull request unmergeable. Please resolve the merge conflicts.

[Dylan-DPC]

The PR this was blocked on, is now closed due to inactivity, which should unblock this pr, so updating the labels

[alex-semenyuk]

@EFanZh
From wg-triage. Any updates on this PR? Could you please resolve merge conflicts

[EFanZh]

@alex-semenyuk: The original ACP suggests that we can add an Arguments::from_str method. I assume its intended signature is fn(&'static str) -> Arguments<'a>, but I don’t think it can be done without significant change to the underlying representation. Now I’ll draft this PR and see if I can come up with something later.

[Dylan-DPC]

@EFanZh any updates on this? Looks like this has hit a roadblock and closing it for now until a new process is thought of might be the best idea but idk if there's any other progress in the meanwhile so checking in

[EFanZh]

Closed for now.

[m-ou-se]

We now have a new implementation of fmt::Arguments that allows for conversion directly from &str.

#148906 exposes fmt::Arguments::from_str() as unstable.

Tracking issue: #148905