IsNever<T>

定義

code:ts

type IsNever<T> = T[] extends never[] ? true : false;

テスト

code:ts

type cases = [

Expect<Equal<IsNever<never>, true>>,

Expect<Equal<IsNever<never | string>, false>>,

Expect<Equal<IsNever<''>, false>>,

Expect<Equal<IsNever<undefined>, false>>,

Expect<Equal<IsNever<null>, false>>,

Expect<Equal<IsNever<[]>, false>>,

Expect<Equal<IsNever<{}>, false>>,

];