[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [Type](https://evolu.dev/docs/api-reference/common/Type) › IsUnionWithNull

```ts
type IsUnionWithNull<U> =
  U extends UnionType<infer Members>
    ? Members extends [AnyType, ...AnyType[]]
      ? NullTypeInMembers<Members>
      : false
    : false;
```

Defined in: [packages/common/src/Type.ts:4449](https://github.com/evoluhq/evolu/blob/e7144e2bbe9069362b62dec1b64a8aa922b8f1b0/packages/common/src/Type.ts#L4449)