code: public boolean canApplyDelayFn(R result, Throwable failure) {
      return (delayResult == null || delayResult.equals(result)) && (delayFailure == null || (failure != null
          && delayFailure.isAssignableFrom(failure.getClass())));
    }
docs: Returns whether any configured delay function can be applied for an execution result.
  
  @see #withDelay(DelayFunction)
  @see #withDelayOn(DelayFunction, Class)
  @see #withDelayWhen(DelayFunction, Object)