Re: [Pyobjc-dev] Bridging of Strings

[David E. <epp...@ic...>]

On 12/23/02 8:30 PM +0100 Ronald Oussoren <ous...@ci...> wrote:
>> ValueError: NSInvalidArgumentException - *** -count only defined for
>> abstract class.  Define -[NSCFArray count]!
>>
>
> That's just like in 'normal' python types: If you call NSArray.count  you
> get the count method defined by NSArray instead of the one defined  by
> the class of your object. That is not very Objective-C-like, but  this is
> needed to implement super(cls, self).count().

A possibly related recent surprise I had:
I had an NSArray object X (or its Python proxy) and attempted to retrieve 
X[-1].
Got an NSRangeError rather than the expected last array item.
Trivial to work around, but shouldn't this work?

> That's not really a problem, just use the strint literal
> "localizedCaseInsentiveCompare:" as the argument off
> NSArray.sortedArrayUsingSelector_. By the time strings NSArray methods
> touch the strings in an array they will be converted to NSString  (that's
> even true if the NSArray is the OC_PythonArray proxy for a  python
> sequence).

Well, except that what I really want to sort isn't an NSArray of strings, 
it's a Python list of Python dictionaries, which I want to sort according 
to the (localized case-independent) string values stored under one of the 
keys in each dictionary.
--
David Eppstein       UC Irvine Dept. of Information & Computer Science
epp...@ic... http://www.ics.uci.edu/~eppstein/