struct SliceCastable

Opt-in trait class for slice conversions.

Declare a specialization of this class for any types that are compatible

with `SliceCast`. Both ways need to be declared (i.e. if

SliceCastable

<A

,B> exists, you should declare

SliceCastable

<B

,A> too).

The type has no members, it's just the existance of the specialization that

unlocks SliceCast usage for a type pair.