python decorators
1. decorators with arguments
example definition
def repeat(num_repeats): def repeat_decorator(func): def repeat_wrapper(*args, **kwargs): for _ in range(num_repeats): value = func(*args, **kwargs) return value return repeat_wrapper return repeat_decorator
usage
@repeat(num_repeats=4) def my_func(x): print("hello")
1.1. explanation
Think of partial function application (see Currying in Haskell). @repeat takes (num_repeats=4) as an argument. It returns a typical decorator function. The decorator function takes the decorated function as input and returns a new function, which is a wrapper around the decorator function. Subsequent calls to the decorated function now go through the wrapper.