array-section

An array where only a (contiguous) subsection of the array may be viewed.

This can be useful in const functions that wish to return an array of size N, but with some elements potentially unused.

#![no_std] compatible

/// Returns an array of the square numbers smaller than both x and N.
const fn squares_smaller_than<const N: usize>(x: usize) -> ArraySection<usize, N> {
   let mut i = 0;
   let mut ans = [0; N];
   while i * i < N && i * i < x {
       ans[i] = i * i;
       i += 1;
   }
   ArraySection::new(ans, 0..i)
}
assert_eq!(squares_smaller_than::<10>(16), [0, 1, 4, 9]);

Features

std: derives the Error trait for the error types.
alloc: enables conversion of the array section into Vecs and Boxed slices.