# reduce

Reduce the values to a single value.

## Signatures

```ts
export declare const reduce: {
    <V, B>(b: B, f: (b: B, value: V) => B): <E, R>(ref: RefHashSet<V, E, R>) => RefSubject.Computed<B, E, R>;
    <V, E, R, B>(ref: RefHashSet<V, E, R>, b: B, f: (b: B, value: V) => B): RefSubject.Computed<B, E, R>;
};
```

## Why

Makes reduce a live projection of the hash set; consumers can sample it now or observe it
without copying the source state.

## Ownership and lifetime

The reduce view retains no independent state. An Effect read samples the source once; Fx
observation follows later pushes and its observing Scope owns subscription cleanup.