Import
import { has } from "@typed/fx/RefStruct";Signatures
export declare const has: {
<S extends object, const K extends keyof S>(key: K): <E, R>(ref: RefStruct<S, E, R>) => RefSubject.Computed<boolean, E, R>;
<S extends object, const K extends keyof S, E, R>(ref: RefStruct<S, E, R>, key: K): RefSubject.Computed<boolean, E, R>;
};Why
Makes has a live projection of the struct; consumers can sample it now or observe it without copying the source state.
Ownership and lifetime
The has 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.