variable / @typed/fx

RefOption.filter

Filter the value inside the Option of a RefOption.

Package version
2.0.0-beta.13
Category
Derived queries
Since
1.18.0
Member of
RefOption

Import

import { RefOption } from "@typed/fx";

Access RefOption.filter through the imported RefOption export. Its declaration below describes the member.

This public exposure is a re-export. Its import path is supported; declaration documentation is shared with the other public exposures below.

Signatures

export declare const filter: {
    <A>(predicate: (a: A) => boolean): <E, R>(ref: RefOption<A, E, R>) => RefSubject.Computed<Option.Option<A>, E, R>;
    <A, E, R>(ref: RefOption<A, E, R>, predicate: (a: A) => boolean): RefSubject.Computed<Option.Option<A>, E, R>;
};

Why

Projects option state with filter for both current reads and future pushes, avoiding a second mutable cache of the derived value.

Ownership and lifetime

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

Other public imports

These import paths expose the same declaration. Each page retains its own public name and signature.

Source