Macro const_for

macro_rules! const_for {
    (($i:ident in $start:tt..$end:tt)  $code:expr ) => { ... };
}

A helper macro for emulating for loops in a const context.

Usage

const fn for_in_const() {
    let mut array = [0usize; 4];
    const_for!((i in 0..(array.len())) { // We need to wrap the `array.len()` in parenthesis.
        array[i] = i;
    });
    assert!(array[0] == 0);
    assert!(array[1] == 1);
    assert!(array[2] == 2);
    assert!(array[3] == 3);
}