Angular Signals su nini?

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**Signals** sune Angular's reactive primitive (aka a cikin Angular 16+) don gudanar da state — wani wrapper a kusa da wata value da **yă sanar consumers lokacin da ya canza**, yana ba da damar fine-grained, efficient updates ba tare da dogaro kan Zone.js change detection. ## Yin signal da amfani da shi ```ts import { signal, computed, effect } from "@angular/core"; export class CounterComponent { count = signal(0); // a writable signal double = computed(() => this.count() * 2); // derived signal (auto-updates) increment() { this.count.set(this.count() + 1); // set a new value this.count.update(c => c + 1); // or update based on current } constructor() { effect(() => { console.log(`count is now ${this.count()}`); // re-runs when count changes }); } } ``` ## Karanta signal: kira shi kamar function ```html ``` Jiya signals sune **an karanta su ta kirowa su** (`count()`), ba kamar plain properties ba. A cikin template, Angular yana lura daidai wane signals view ya karanta, saboda haka kawai sassa da aka shafa suke yadda za su sabunta lokacin da signal ya canza. ## Signal nau'ikan uku ```text signal(value) → writable state, updated via .set() / .update() computed(() => ...) → derived/cached value; auto-recomputes when its deps change effect(() => ...) → runs a side effect whenever read signals change ``` `computed` shine lazy da cached (kamar Vue's computed); `effect` yana gudnar da side effects reactively (kamar watcher). ## Me yasa signals suka danganta: fine-grained reactivity ```text Traditional Angular: a change triggers checking the WHOLE component tree (Zone.js) Signals: Angular knows EXACTLY which views depend on a changed signal → update only those → far more efficient, and enables "zoneless" Angular ``` Signals sune ba da Angular **precise dependency tracking** — lokacin da signal ya canza, kawai views da computeds da suka karanta shi ne suke yadda su sabunta. Wannan yana zama mai tasiri fiye da faɗaɗɗen change detection Zone.js yake bugi, kuma shine tushe don cire Zone.js gaba daya (zoneless mode). ## Signal-based inputs (saba) ```ts name = input(); // @Input as a signal name = input.required(); ``` ## Me yasa ya dangata Signals sune mafi muhimmin banza a nan gida a cikin Angular's reactivity — wani sauƙi, mafi shahara, da matsakaici mafi tasiri model fiye da implicit Zone.js change detection. Su sune tare da damar fine-grained updates, sauƙi rashin bukatun bincike, haɗawa tsada da computed/effect, da bugi jiya ga zoneless Angular. Jira signals shine mai karfafa karuwa, kamar yadda Angular take tutarwa sababbin haɗin gwiwa zuwa su azaman default state primitive.