Jim Jewett wrote:
> On 4/19/06, Nick Coghlan <[EMAIL PROTECTED]> wrote:
>
>> Then you'd have:
>>
>> def f(a, *(b, c=1, *args), **(d, e=2, **kwds)):
>> # Silly function
>>
>> 'a' would be a normal positional-or-keyword argument
>> 'b' would be a required positional-only argument
>
> Am I reading that correctly?
>
> Looking only at a and b the possible calling signatures are exactly:
>
> f(1, 2)
> f(a=1, 2)
>
> because b can't be named but must appear second, and nothing except a
> can appear before it because of the rules on positional arguments.
Both would be illegal. The first one misses the required keyword argument 'd',
the second one is a SyntaxError because you can't have a keyword argument
before a positional one.
Some legal combinations:
f(1, 2, 3, d=1) # Positional args a, b and c
f(1, 2, 3, 4, 5, 6, d=1) # Positional args a, b and c and (4, 5, 6) as args
f(2, a=1, d=1) # Provide a as a keyword arg instead
You'd never define a function with a signature as insane as the one in the
example though - you'd only use it for cases where you accepted arbitray
keyword arguments, but wanted to permit some positional arguments (like
'self') without accidental conflicts.
This seems to be more of a theoretical problem than a practical one though. . .
Cheers,
Nick.
--
Nick Coghlan | [EMAIL PROTECTED] | Brisbane, Australia
---------------------------------------------------------------
http://www.boredomandlaziness.org
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