Function fn_memo::sync::memoize_rw_lock

pub fn memoize_rw_lock<Arg, Output, F>(
    f: F
) -> impl FnMemo<Arg, Output> where
    Arg: Clone + Eq + Hash,
    Output: Clone,
    F: RecurFn<Arg, Output>, 

Creates a synchronized memoization of f using HashMap with RwLock as cache.