Menu
When using rxjs in angular 2,
is there any difference between
import { Observable } from 'rxjs/Observable'
and
import { Observable } from 'rxjs'?
899
import {Observable} from 'rxjs/Observable'; would import the Observable, but you don't need to import it all if you are using promises... toPromise works without it.
RxJS introduces Observables, a new Push system for JavaScript. An Observable is a Producer of multiple values, "pushing" them to Observers (Consumers). A Function is a lazily evaluated computation that synchronously returns a single value on invocation.
Observable are just that — things you wish to observe and take action on. Angular uses the Observer pattern which simply means — Observable objects are registered, and other objects observe (in Angular using the subscribe method) them and take action when the observable object is acted on in some way.
An RxJS Subject is a special type of Observable that allows values to be multicasted to many Observers. While plain Observables are unicast (each subscribed Observer owns an independent execution of the Observable), Subjects are multicast. A Subject is like an Observable, but can multicast to many Observers.
Yes there is a slight difference which is the bundle size. If you aren't using tree shaking library like rollup.js which remove all unnecessary codes, your bundle will be large when importing from 'rxjs' as you are importing everything even if you are using only the Observable. On the other hand if you import from 'rxjs/Observable' you are only importing what you need and the bundle will be smaller.
Import only what you need and patch Observable (this is useful in size-sensitive bundling scenarios)
Ref: https://github.com/ReactiveX/rxjs
63
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
