Decorator Base Class: Needs improvement.

[Steve Holden]

Ron_Adam wrote:
> On Tue, 05 Apr 2005 02:55:35 -0400, Steve Holden <steve at holdenweb.com>
> wrote:
> 
> 
>>Ron_Adam wrote:
>>
>>>Ok, that post may have a few(dozen?) problems in it.  I got glitched
>>>by idles not clearing variables between runs, so it worked for me
>>>because it was getting values from a previous run.
>>>
>>>This should work better,  fixed a few things, too.
>>>
>>>The decorators can now take more than one argument.
>>>The function and arguments lists initialize correctly now.
>>>
>>
>>Ron:
>>
>>I've followed your attempts to understand decorators with interest, and 
>>have seen you engage in conversation with many luminaries of the Python 
>>community, so I hesitate at this point to interject my own remarks.
> 
> 
> I don't mind.  It might help me communicate my ideas better.
> 
> 
>>In a spirit of helpfulness, however, I have to ask whether your 
>>understanding of decorators is different from mine because you don't 
>>understand them or because I don't.
> 
> 
> Or it's just a communication problem, and we both understand.
> Communicating is not my strongest point. But I am always willing to
> clarify something I say.
> 
> 
>>You have several times mentioned the possibility of a decorator taking 
>>more than one argument, but in my understanding of decorators this just 
>>wouldn't make sense. A decorator should (shouldn't it) take precisely 
>>one argument (a function or a method) and return precisely one value (a 
>>decorated function or method).
>>
>>
>>>It doesn't work with functions with more than one variable.  It seems
>>>tuples don't unpack when given to a function as an argument.  Any way
>>>to force it?
> 
> 
> What I was referring to is the case:
> 
>     @decorator(x,y,z) 
> 
> As being a decorator expression with more than one argument.  and not:
> 
>     @decorator(x)(y)
> 
> This would give a syntax error if you tried it.
> 
> 
>>>>@d1(1)(2)
> 
> SyntaxError: invalid syntax
> 
> The problem I had with tuple unpacking had nothing to do with
> decorators.  I was referring to a function within the class, and I
> needed to be consistent with my use of tuples as arguments to
> functions and the use of the '*' indicator.
> 
> 
>>Do you understand what I mean when I say a decorator should take one 
>>function as its argument and it should return a function?
>>
>>regards
>> Steve
> 
> 
> Hope this clarifies things a bit.
> 
> Cheers,
> Ron
> 
> 
So what you are saying is that you would like to be able to use 
arbitrarily complex expressions after the :at" sign, as long as they 
return a decorator? If so, you've been "pronounced" :-)

regards
  Steve
-- 
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