Macro fold 

macro_rules! fold {
    ($($fold_args:tt)*) => { ... };
}

Folds an array into a single value in const contexts.

Examples

use const_tools::{fold, destructure};

const fn last<T, const N: usize>(value: [T; N]) -> Option<T> {
    fold!(value, None, |prev, item| {
        std::mem::forget(prev); // Can't drop in const context, for the sake of illustration
        Some(item)
    })
}