pairwise

signature: pairwise(): Observable<Array>

Emit the previous and current values as an array.

Ultimate RxJS

Examples

Example 1:

( StackBlitz | jsBin | jsFiddle )

// RxJS v6+
import { pairwise, take } from 'rxjs/operators';
import { interval } from 'rxjs';
//Returns: [0,1], [1,2], [2,3], [3,4], [4,5]
interval(1000)
.pipe(
pairwise(),
take(5)
)
.subscribe(console.log);

Additional Resources

📁 Source Code: https://github.com/ReactiveX/rxjs/blob/master/src/internal/operators/pairwise.ts