[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [objc-improvements] Warnings when compiling GNUStep

From: Ziemowit Laski
Subject: Re: [objc-improvements] Warnings when compiling GNUStep
Date: Thu, 4 Sep 2003 14:26:56 -0700

On Thursday, Sep 4, 2003, at 02:07 US/Pacific, Nicola Pero wrote:

but since Objective-C allows multiple root classes, the compiler
cannot statically decide to focus on NSObject.
What should we do?  I see 3 choices:
   (1) Leave things as they are.  Users will be able to suppress the
above warning by
casting the receiver to the root class (in above case, '(NSObject
(2) Build a list of all plausible root classes (i.e., classes without
       and consult all instance methods for those classes when
dispatching messages to
(3) Treat messages to 'Class' the same way we treat messages to 'id',
i.e., consult
       all class and instance methods available.  This is what the
compiler appears to
       have done until now (in its mercurial and buggy way).

I've implemented 2. in my patch, and I think this is correct and
consistent with the intention of the current behavior.

I agree.  That is what should happen.  When looking up methods of a
receiver of type 'Class', an instance method of a non-root class should
not be found (big warning!); an instance method of a root class should be found (no warning if only one is found, warning if conflicting methods are
found).  I think this is correct because this is how messaging works.

Yes, I've come around on this issue also. :-) So long as the implementation is efficient (and I too now realize there's no reason why it couldn't be),
we should look among root class instance methods as a last resort.

Ziemowit Laski                 1 Infinite Loop, MS 301-2K
Mac OS X Compiler Group        Cupertino, CA USA  95014-2083
Apple Computer, Inc.           +1.408.974.6229  Fax .5477

reply via email to

[Prev in Thread] Current Thread [Next in Thread]