On May 10, 2016, at 16:05 , Carl Hoefs <newsli...@autonomy.caltech.edu> wrote: > > I'm not sure how context is to be used here
It has to be a value that’s unique to the piece of code that tests it. In effect, this means unique to the class that creates and responds to the observations. If you’re in Obj-C, the usual trick is to use the static address of something, like this: > static void* kvoContext = &kvoContext; This exploits a quirk of C to initialize the static variable as containing its own address. That means you can specify the ‘context:’ parameter as EITHER ‘kvoContext’ OR ‘&kvoContext’, so that forgetting the & is harmless. _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
