[PEAK] Re: generic functions and keyword arguments

[Vladimir Iliev]

Phillip J. Eby написа:
> At 09:57 AM 8/4/2008 +0300, Vladimir Iliev wrote:
>> Phillip J. Eby написа:
>>> At 05:14 PM 8/2/2008 +0300, Vladimir Iliev wrote:
>>>> hi, can i somehow use keyword arguments with peak.rules based 
>>>> generic functions ?
>>> Arguments passed by keyword are treated the same as arguments passed 
>>> by position, so e.g.:
>>>  def a(b, c):
>>>      ...
>>> can be called with "a(c=1,b=2)".   If you mean, can you do this:
>>>
>>>   def a(**kw):
>>> and then test for whether the caller passed in b=2, you would use 
>>> rules like:
>>>   @when(a, "'b' in kw and kw['b']==2")
>>> in order to dispatch on arguments that are not part of the generic 
>>> function's "def" signature.
>>
>> no, i just want to pass arguments that are not part of the signature 
>> through the gf.
>>
>> if i do this:
>>
>> @abstract
>> def func(x, **k):
>>     pass
>>
>> @when(func, (str,))
>> def func_str(x, **k):
>>     print 'str'
>>
>>
>> func('x', y=5)
>>
>> i'm getting TypeError: callback() got an unexpected keyword argument 'y'
> 
> Hmm.  I'm getting this:
> 
> Python 2.5.1 (r251:54863, Nov 28 2007, 17:53:19) [MSC v.1310 32 bit 
> (Intel)] on
> win32
> Type "help", "copyright", "credits" or "license" for more information.
>  >>> from peak.rules import *
>  >>> @abstract
> ... def func(x, **k): pass
> ...
>  >>> @when(func,(str,))
> ... def fstr(x,**k): print 'str'
> ...
>  >>> func('x')
> str
>  >>> func('x',y=42)
> str
>  >>> func('x', y=5)
> str
>  >>>
> 
> Are you sure that's all the code needed for you to reproduce the problem?

yes. i didn't mentioned that i'm using python 2.4