# RefSubject.HydratedRefSubject

Defines the hydrated ref subject state contract.

## Signatures

```ts
export interface HydratedRefSubject<A, E = never, R = never, RH = R> extends RefSubject<A, E, R>, HydrationRef<E, RH> {
}
```

```ts
export declare namespace HydratedRefSubject {
    type Any = HydratedRefSubject<any, any, any, any>;
    type HydrationError<T> = T extends HydrationRef<infer E, any> ? E : never;
    type HydrationServices<T> = T extends HydrationRef<any, infer R> ? R : never;
}
```

## Why

Combines writable renderer-independent state with its hydration boundary so restoration precedes
ordinary pushed updates.

## Ownership and lifetime

HydratedRefSubject is a contract and performs no acquisition. Implementations retain the errors,
services, interruption, and Scope requirements expressed by its members.