javascript / intermediate
Snippet
Merging Streams with combineLatest
The 'combineLatest' operator merges multiple Observables into one. It emits a new array of values whenever any of the source Observables emit, provided all sources have emitted at least once. This is perfect for creating a 'View Model' object for your templates.
snippet.js
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export class DashboardComponent {private user$ = this.userService.currentUser$;private settings$ = this.settingsService.preferences$;vm$ = combineLatest([this.user$, this.settings$]).pipe(map(([user, settings]) => ({username: user.name,theme: settings.theme,isReady: true})));}
angular
Breakdown
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combineLatest([this.user$, this.settings$])
Waits for all Observables to emit and then combines their latest values.
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map(([user, settings]) => ...)
Transforms the array of values into a single structured object.