Method _getChipStream

src/material/chips/chip-set.ts:205–212

* Gets a stream of events from all the chips within the set. * The stream will automatically incorporate any newly-added chips.

(
    mappingFunction: (chip: C) => Observable<T>,
  )

   * The stream will automatically incorporate any newly-added chips.
   */
  protected _getChipStream<T, C extends MatChip = MatChip>(
    mappingFunction: (chip: C) => Observable<T>,
  ): Observable<T> {
    return this._chips.changes.pipe(
      startWith(null),
      switchMap(() => merge(...(this._chips as QueryList<C>).map(mappingFunction))),
    );
  }

  /** Checks whether an event comes from inside a chip element. */
  protected _originatesFromChip(event: Event): boolean {