Terry Reedy於 2012年9月15日星期六UTC+8上午4時40分32秒寫道：
> 2nd try, hit send button by mistake before
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> On 9/14/2012 5:28 AM, Jean-Michel Pichavant wrote:
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> > Decorators are very popular so I kinda already know that the fault is
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> > mine. Now to the reason why I have troubles writing them, I don't
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> > know. Every time I did use decorators, I spent way too much time
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> > writing it (and debugging it).
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> You are writing parameterized decorators, which require inverted
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> currying of the wrapper maker. Perhaps that is why you have trouble. As
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> I showed in response to Cameron, it may be easier to avoid that by using
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> a traditional post-def wrapping call instead of decorator syntax.
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> --
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> Terry Jan Reedy
I'll give another example to show the decorators in python in
versions above 2.4 .
# a general function with the variable input : def fname( *argc, **argn)
# a deco is a mapping from an input funtion to another function
def deco( fn, *list_in, **dict_in): # use list_in and dict_in to modify fn
""" deco wrapper """ # deco.__doc__
#print list_in, dict_in, " in the deco"
def wrapper( fn, *argc, **argan): # to be returned as a function
# do things one wants before calling fn
result=fn(*argc, **argn) # call the original, save the result
# do things after calling fn
return result
# enhance the wrapper and get info of fn
wrapper.__doc__=fn.__doc__
# enhance wrapper with result, fn, list_in, dict_in
#....
return wrapper
def f1():
""" doc of f1"""
print "inside f1"
f2=deco(f1, 2,3,4,5,6, MSG="deco f1 to f2")
f2() # invoke the decorated function from f1
# For a deco maps a deco to another deco can be done similarly
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