debounce-time-after.ts

import { OperatorFunction, SchedulerLike, concat } from "rxjs";
import { async } from "rxjs/internal/scheduler/async";
import { debounceTime, publish, take } from "rxjs/operators";

export function debounceTimeAfter<T>(
  amount: number,
  dueTime: number,
  scheduler: SchedulerLike = async,
): OperatorFunction<T, T> {
  return publish(value =>
    concat(
      value.pipe(take(amount)),
      value.pipe(debounceTime(dueTime, scheduler)),
    )
  );
}

export function debounceTimeAfterFirst<T>(
  dueTime: number,
  scheduler: SchedulerLike = async,
): OperatorFunction<T, T> {
  return debounceTimeAfter<T>(1, dueTime, scheduler);
}