When I reach for .windows(), I always find that I want to use it like this: let slice = ['l', 'O', 'R', 'e', 'm']; for [a , b] in slice.windows(2) { if a.is_uppercase() && b.is_uppercase() { println!("Found consecutive capitals: {a}{b}"); } } But this doesn't compile because: err…

While waiting for array_windows to stabilize, you could also use tuple_windows from the itertools crate.

[image] nk9: `` specify that it's an iterator which always returns slices of length size unfortunately, the size is not represented at type level. the array_windows() does what you expect, but it is not stable yet. EDIT: the easy workaround is to manually convert the slice into array: // p…

windows() is documented to always return a specific length, but the compiler can't read documentation when performing pattern exhaustiveness checking. What you need is array_windows() (currently unstable).

Thanks all for your speedy and informative comments. Hoping stabilization is in the cards soon, but it's good to know I have options in the meantime.

Implement your own array_windows in the meantime: fn array_windows<T: Copy, const LEN: usize>(slice: &[T]) -> impl Iterator<Item = [T; LEN]> { slice.windows(LEN).map(|window| window.try_into().unwrap()) } fn main() { let slice = ['l', 'O', 'R', 'e', 'm']; for [a, b] in array_windows(&s…

This is really slick, thanks. I would not have expected the compiler to be able to infer that LEN generic.

While let is another option. let slice = ['l', 'O', 'R', 'e', 'm']; let mut iter = slice.windows(2); while let Some([a, b]) = iter.next(){ if a.is_uppercase() && b.is_uppercase() { println!("Found consecutive capitals: {a}{b}"); } }

`for`-loops, pattern matching, and .windows(usize)

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`for`-loops, pattern matching, and .windows(usize)

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