Decorator factory with arguments

Question

Accepted Answer

When a decorator needs its own arguments, you need three levels of nesting. repeat(3) is called first and returns decorator. That decorator is then applied to say, returning wrapper. So @repeat(3) def say(...) is equivalent to say = repeat(3)(say). The extra layer exists purely to capture the argument - repeat is a decorator factory, not a decorator itself. This triple-nesting pattern trips people up initially, but once you see it as 'factory -> decorator -> wrapper' it clicks.