Question

I have a small class with a timer, but don’t have anything for the timer to do when it expires. Since Timer extends Thread, I get all I want to know from calling timer.isAlive(). Since Timer requires a function parameter, I’m looking for an anonymous ‘nop’ function that doesn’t clutter the class, and came up with this;

  def ready(self, node):
    def nop(): pass
    delay = node.find('delay')
    seconds = float(delay.get('seconds'))
    self.timer = Timer(seconds, nop)
    return True;

It seems to work with my little test programs. Having not tried this before, or seen this as an example anywhere, I’m wondering, is this truly safe?

Answer 1

Your code is fine. Functions doing nothing aren’t dangerous — they just do nothing. Using a lambda function would make the code a bit more concise:

self.timer = Timer(seconds, lambda: None)