Type Alias And<A, B>

Example

import type {And} from 'type-fest';

type TT = And<true, true>;
//=> true

type TF = And<true, false>;
//=> false

type FT = And<false, true>;
//=> false

type FF = And<false, false>;
//=> false
Copy

Note: When boolean is passed as an argument, it is distributed into separate cases, and the final result is a union of those cases. For example, And<true, boolean> expands to And<true, true> | And<true, false>, which simplifies to true | false (i.e., boolean).

Example

import type {And} from 'type-fest';

type A = And<true, boolean>;
//=> boolean

type B = And<boolean, true>;
//=> boolean

type C = And<false, boolean>;
//=> false

type D = And<boolean, false>;
//=> false

type E = And<boolean, boolean>;
//=> boolean
Copy

Note: If either of the types is never, the result becomes false.

Example

import type {And} from 'type-fest';

type A = And<true, never>;
//=> false

type B = And<never, true>;
//=> false

type C = And<false, never>;
//=> false

type D = And<never, false>;
//=> false

type E = And<boolean, never>;
//=> false

type F = And<never, boolean>;
//=> false

type G = And<never, never>;
//=> false
Copy