Function mapped 

pub fn mapped<E, O, const N: usize>(
    x: &[Arg<'_, E>; N],
    n: usize,
    out: &mut [MaybeUninit<O>],
    f: impl Fn([E; N]) -> (O, bool),
) -> bool
where
    E: Copy,

Writes f for each of n results into out, for arguments x, and gives whether f said true for every result. One and two arguments run through [pairs_into], and three through triples_into, whose loops vectorize.