Function map_into 

pub fn map_into<D: Copy + Send + Sync, A: Copy + Send + Sync, Op: ElementOp<A>>(
    dest: &mut StridedViewMut<'_, D>,
    src: &StridedView<'_, A, Op>,
    f: impl MapFn<A, D>,
    exec: Exec<'_>,
) -> Result<()>

Apply a function element-wise from source to destination.

The element operation Op is applied lazily when reading from src. Source and destination may have different element types.

f is any Fn(A) -> D + Sync, gated as KernelClass::Map, or a function declared with a class of its own (see MapFn), so an expensive element function forks sooner.