pub fn flat_map_singleton<A, B>()Expand description
(open)
{}ensures
forall<x: A, f: Mapping<A, Seq<B>>> Seq::singleton(x).flat_map(f) == f.get(x)
pub fn flat_map_singleton<A, B>()(open)
{}ensures
forall<x: A, f: Mapping<A, Seq<B>>> Seq::singleton(x).flat_map(f) == f.get(x)