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collectValues()

caution

This function is deprecated. partitionByKey with combineKeys covers its intended use case.

A pipeable operator that collects all the GroupedObservables emitted by the source and emits a Map with the latest values of the inner Observables.

function collectValues<K, V>(): OperatorFunction<GroupedObservable<K, V>, Map<K, V>>

Returns​

OperatorFunction<GroupedObservable<K, V>, Map<K, V>>: An Observable that emits a Map with the latest value for each key in the source grouped Observables.

Example​

import { Subject } from 'rxjs'
import { mapTo, scan, takeWhile } from 'rxjs/operators'
import { collectValues, split } from '@react-rxjs/utils'

const votesByKey$ = new Subject<{ key: string }>()
const counters$ = votesByKey$.pipe(
  split(
    (vote) => vote.key,
    (votes$) =>
      votes$.pipe(
        mapTo(1),
        scan((count) => count + 1),
        takeWhile((count) => count < 3),
      ),
  ),
  collectValues(),
)

counters$.subscribe((counters) => {
  console.log("counters$:")
  counters.forEach((value, key) => {
    console.log(`${key}: ${value}`)
  })
})

votesByKey$.next({ key: "foo" })
// > counters$:
// > foo: 1

votesByKey$.next({ key: "foo" })
// > counters$:
// > foo: 2

votesByKey$.next({ key: "bar" })
// > counters$:
// > foo: 2
// > bar: 1

votesByKey$.next({ key: "foo" })
// > counters$:
// > bar: 1

votesByKey$.next({ key: "bar" })
// > counters$:
// > bar: 2
//
votesByKey$.next({ key: "bar" })
// > counters$:

See also​