Function removeNullFromUnion

src/Type.ts:397–403

(t: UnionType)

}

export function removeNullFromUnion(t: UnionType): [PrimitiveType | null, OrderedSet<Type>] {
    const nullType = t.findMember("null");
    if (!nullType) {
        return [null, t.members];
    }
    return [nullType as PrimitiveType, t.members.filterNot(isNull).toOrderedSet()];
}

export function nullableFromUnion(t: UnionType): Type | null {
    const [hasNull, nonNulls] = removeNullFromUnion(t);