octarine-joins/src/main/java/com/codepoetics/octarine/joins/Joiner.java
public Stream<T2<L, Set<R>>> strictOneToMany(Collection<? extends R> rights) {
        return strictOneToMany(rights.stream());
    }
public Stream<T2<L, Set<R>>> strictOneToMany(Collection<? extends R> rights) {
        return strictOneToMany(rights.stream());
    }
Strict one to many