# filterMap

Filter-maps a Versioned's output as both an Fx and Effect; the Effect value becomes `Option` (Some when the predicate holds, None otherwise).

## Signatures

```ts
export declare const filterMap: {
    <A, E, R, C, B, D>(options: {
        onFx: (a: A) => Option.Option<C>;
        onEffect: (b: B) => Option.Option<D>;
    }): <R0, E0, R2, E2>(versioned: Versioned<R0, E0, A, E, R, B, E2, R2>) => Versioned<never, never, C, E, R, Option.Option<D>, E0 | E2, R0 | R2>;
    <R0, E0, A, E, R, B, E2, R2, C, D>(versioned: Versioned<R0, E0, A, E, R, B, E2, R2>, options: {
        onFx: (a: A) => Option.Option<C>;
        onEffect: (b: B) => Option.Option<D>;
    }): Versioned<never, never, C, E, R, Option.Option<D>, E0 | E2, R0 | R2>;
};
```

## Why

Drops absent pushed values while preserving an Option for the current read, making the two
absence semantics explicit.

## Ownership and lifetime

filterMap does not take ownership of its inputs. Its observation and current-read channels
retain upstream lifetime, typed failures, services, and interruption behavior.