Add trim_prefix and trim_suffix methods for both slice and str types.

[deven]

Implements trim_prefix and trim_suffix methods for both slice and str types, which remove at most one occurrence of a prefix/suffix while always returning a string/slice (rather than Option), enabling easy method chaining.

Tracking issue

#142312

API

impl str { pub fn trim_prefix<P: Pattern>(&self, prefix: P) -> &str; pub fn trim_suffix<P: Pattern>(&self, suffix: P) -> &str where for<'a> P::Searcher<'a>: ReverseSearcher<'a>; } impl<T> [T] { pub fn trim_prefix<P: SlicePattern<Item = T> + ?Sized>(&self, prefix: &P) -> &[T] where T: PartialEq; pub fn trim_suffix<P: SlicePattern<Item = T> + ?Sized>(&self, suffix: &P) -> &[T] where T: PartialEq; }

Examples

// Method chaining assert_eq!(" <https://example.com/> ".trim().trim_prefix('<').trim_suffix('>').trim(), "https://example.com/"); // Slices let v = &[10, 40, 30]; assert_eq!(v.trim_prefix(&[10]), &[40, 30][..]);

ACP

Originally proposed in rust-lang/libs-team#597

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r? @joboet

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[deven]

r? @Amanieu

[deven]

r? @joboet

[Amanieu]

@bors r+

[bors]

📌 Commit 32cb8f1 has been approved by Amanieu

It is now in the queue for this repository.