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lending iterator

An iterator-like type whose items borrow from the iterator itself, so only one can be held at a time.

Defined with a GAT (type Item<'a> where Self: 'a; fn next<'a>(&'a mut self)); std has no such trait, so it's driven with while let.

Examples

  • With a lending ScanReader, let a = r.next(); let b = r.next(); fails with E0499 if a is still used, since each item borrows r mutably.

See also

generic associated type Iterator trait mutable reference
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