# RefHashSet.add

Add a value to the RefHashSet.

## Signatures

```ts
export declare const add: {
    <V>(value: V): <E, R>(ref: RefHashSet<V, E, R>) => Effect.Effect<HashSet.HashSet<V>, E, R>;
    <V, E, R>(ref: RefHashSet<V, E, R>, value: V): Effect.Effect<HashSet.HashSet<V>, E, R>;
};
```

## Why

Add a value to the RefHashSet. The operation remains attached to the RefSubject's versioned
state boundary.

## Ownership and lifetime

Running add performs one serialized hash set transition and resolves with its committed value.
It acquires no resource; failures and services remain those of the source ref.