static <A, B, C> MultiSetMap<B, C> lambdaMapLike mapMultiSetMapKeys(IF1<A, C> f, MultiSetMap<A, B> mm) { MultiSetMap m = similarEmptyMultiSetMap(mm); for (key : keys(mm)) m.put(f.get(key), mm.get(key)); ret m; } static <A, B, C> MultiSetMap<B, C> lambdaMapLike mapMultiSetMapKeys(MultiSetMap<A, B> mm, IF1<A, C> f) { ret mapMultiSetMapKeys(f, mm); }