# RefDuration.RefDuration

A RefDuration is a RefSubject specialized over a Duration value.

## Signatures

```ts
export interface RefDuration<in out E = never, out R = never> extends RefSubject.RefSubject<Duration.Duration, E, R> {
}
```

## Why

Defines duration state with the same current-read, pushed-update, and synchronized-write
contract as RefSubject.

## Ownership and lifetime

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