3 ms·

let numbers = [0, 1, 2]; let doubled = numbers.map(|x| x * 2); You wouldn't want to have to explicitly type out the length of the second array.

• tomjakubowski 4y ago
  That isn't really inferring the size of the array though. [T; N]::map(impl FnMut(T) -> U) defines its return type as [U; N]. N is fixed at the original array literal. https://doc.rust-lang.org/std/primitive.array.html https://doc.rust-lang.org/std/primitive.array.html
  • brundolf 4y ago
    It's inferring it from the array literal in the first place, but it is a different kind of inference from the original one. But I think that's what the question was asking for: > What's a sane/legit use case of such inferring in general? Depends how you interpret "such inferring"
  • dymk 4y ago
    It's inferring the size of `doubled`
    • deleted 4y ago
      [deleted]