Hi, I follow a tutorial to learn decorator:
http://simeonfranklin.com/blog/2012/jul/1/python-decorators-in-12-steps/ I use Enthought Canopy to run the following code. It is really strange that the wrapper does not take effect. In fact, I go back to the basic way (not with @): wrapper(sub(two, one)) Out[38]: <function checker> When I use the non-wrapper mode, it has Coord print out. If I use wrapper, it has nothing to print out. Due to no debug mode help, I don't see anything wrong yet. (add(two, one)) # nothing print out (sub(two, three)) Out[43]: Coord:-- {'y': 300, 'x': 400} # correct is here Anyone can help? Thanks, ............ class Coordinate(object): def __init__(self, y, x): self.y = y self.x = x def __repr__(self): return "Coord:-- " + str(self.__dict__) def add(a, b): return Coordinate(a.x + b.x, a.y + b.y) def sub(a, b): return Coordinate(a.x - b.x, a.y - b.y) def wrapper(func): def checker(a, b): # 1 if a.x < 0 or a.y < 0: a = Coordinate(a.x if a.x > 0 else 0, a.y if a.y > 0 else 0) if b.x < 0 or b.y < 0: b = Coordinate(b.x if b.x > 0 else 0, b.y if b.y > 0 else 0) ret = func(a, b) if ret.x < 0 or ret.y < 0: ret = Coordinate(ret.x if ret.x > 0 else 0, ret.y if ret.y > 0 else 0) return ret return checker one = Coordinate(100, 200) two = Coordinate(300, 200) three = Coordinate(-100, -100) add = wrapper(add) #sub = wrapper(sub) -- https://mail.python.org/mailman/listinfo/python-list
