variable / @typed/fx/RefStruct

pick

Pick properties from the current state of a RefStruct.

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

Import

import { pick } from "@typed/fx/RefStruct";

Signatures

export declare const pick: {
    <S extends object, const Keys extends ReadonlyArray<keyof S>>(keys: Keys): <E, R>(ref: RefStruct<S, E, R>) => RefSubject.Computed<Pick<S, Keys[number]>, E, R>;
    <S extends object, const Keys extends ReadonlyArray<keyof S>, E, R>(ref: RefStruct<S, E, R>, keys: Keys): RefSubject.Computed<Pick<S, Keys[number]>, E, R>;
};

Why

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

Ownership and lifetime

The pick 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