type-fest/source/if-never.d.ts

A collection of essential TypeScript types

import type {IsNever} from './is-never';

/**
An if-else-like type that resolves depending on whether the given type is `never`.

@see {@link IsNever}

@example
```
import type {IfNever} from 'type-fest';

type ShouldBeTrue = IfNever<never>;
//=> true

type ShouldBeBar = IfNever<'not never', 'foo', 'bar'>;
//=> 'bar'
```

@category Type Guard
@category Utilities
*/
export type IfNever<T, TypeIfNever = true, TypeIfNotNever = false> = (
	IsNever<T> extends true ? TypeIfNever : TypeIfNotNever
);