Crate iter_fixed

Provides a type and traits for turning collections of fixed size, like arrays, into IteratorFixed which can be used a bit like an ordinary Iterator but with a compile time guaranteed length. This enables us to turn them back into collections of fixed size without having to perform unnecessary checks during run time.

IteratorFixed provides on stable methods like map, inspect, enumerate, zip, rev, copied, cloned, with nightly skip, step_by, chain, take, flatten.

However it does not and will never be able to support methods like filter or take_while which will affect the length during runtime.

⚠️ Experimental

This code is currently very experimental, type names, function names, trait bounds etc. are all very much subject to change.

Origin

This project is inspired by @leonardo-m ’s idea https://github.com/rust-lang/rust/issues/80094#issuecomment-749260428

Examples:

// simply reverse an Array
let rev_array: [_; 4] = [1, 3, 2, 7]
    .into_iter_fixed()
    .rev()
    .collect();
assert_eq!(rev_array, [7, 2, 3, 1]);

// .. and compute sum with values of a second array multiplied by 10
let sum_array: [_; 4] = rev_array
    .into_iter_fixed()
    .zip([4,1,3,7])
    .map(|(a, b)| a + (b * 10))
    .collect();
assert_eq!(sum_array, [47, 12, 33, 71]);

You can also take a look at examples : matrix.rs and vector.rs

Structs

IteratorFixed

Iterator of fixed size

Traits

FromIteratorFixed

Conversion from an IteratorFixed.

IntoIteratorFixed

Conversion into an IteratorFixed.

Functions

from_fn

Creates a new iterator of fixed size where each iteration calls the provided closure F: FnMut(usize) -> T