Nullish(Nil)
널 병합 연산자(Nullish Coalescing)에서 차용한 타입
type Nullish = null | undefined;
type Nullable<T> = T | Nullish;
function isUndefined(value: unknown): value is undefined {
return value === undefined;
}
function isNotUndefined<T>(
value: T
): value is Exclude<T, undefined> {
return value !== undefined;
}
function isNull(value: unknown): value is null {
return value === null;
}
function isNotNull<T>(value: T): value is Exclude<T, null> {
return value !== null;
}
function isNullish(value: unknown): value is Nullish {
return isNull(value) || isUndefined(value);
}
function isNotNullish<T>(
value: T
): value is NonNullable<T> {
return !isNullish(value);
}
참고 자료
Last updated