issue_comments

I think I made a mistake when I designed the initial decorator. I should have had it work like this:

python @db.register_function() def reverse_string(s): return "".join(reversed(list(s))) As this leaves open the option to add new parameters in the future.

To avoid breaking backwards compatibility I'll use the hack that detects the argument this time, but in the future I'll try to remember to always design decorators to be called like @decorator().

https://stackoverflow.com/a/3931903 looks useful: python def trace(*args): def _trace(func): def wrapper(*args, **kwargs): print enter_string func(*args, **kwargs) print exit_string return wrapper if len(args) == 1 and callable(args[0]): # No arguments, this is the decorator # Set default values for the arguments enter_string = 'entering' exit_string = 'exiting' return _trace(args[0]) else: # This is just returning the decorator enter_string, exit_string = args return _trace Can improve that code with functools.wraps.