this is decorator, this is how it's may be implented >>> def returns(t): ... def dec(f): ... def wrapped(*args, **kwargs): ... ret = f(*args, **kwargs) ... assert type(ret) is t ... return ret ... return wrapped ... return dec ... >>> >>> @returns(int) ... def f1(): ... return 1 ... >>> @returns(float) ... def f2(): ... return 2.0 ... >>> @returns(str) ... def f3(): ... return 1 ... >>> f1() 1 >>> f2() 2.0 >>> f3() Traceback (most recent call last): File "<stdin>", line 1, in ? File "<stdin>", line 5, in wrapped AssertionError >>>
I can imagine that stuff like this may be extremely usefull when testing you program later one could parse and remove all such assertations easy and cut them all at once Regards, Daniel -- http://mail.python.org/mailman/listinfo/python-list
