> On Oct 19, 2014, at 00:19 , Quincey Morris > <quinceymor...@rivergatesoftware.com> wrote: > > On Oct 18, 2014, at 23:46 , Rick Mann <rm...@latencyzero.com> wrote: >> >> The rules on initializers don't make sense to me, in all honesty. > > Yes, but that tells us more about you than about Swift — specifically, it > tells us that you’re more focused on what would ease your coding task in this > one case than on embracing more formal relationships between initializers. > Understandable, but not really useful to anyone else, if you’ll forgive my > saying so. > >> If you imagine that instantiating the base class by calling any of the >> initializers results in a completely instantiated object, the subclass >> should also be able to call any of the inherited initializers. > > Yes, but … > > (It’s all about the “yes, but”s.) > > … calling *up* from a subclass convenience initializer bypasses all of the > subclass designated initializers (except in the case that the subclass > overrides some or all of the superclass's, which introduces its own semantic > ambiguities). That means that the subclass can’t be sure it initialized its > own properties, since that’s the purview of designated initializers — at > least not without supplementary rules. That in turn destroys the integrity of > Swift’s 2-pass initialization process.
Well, I'm not sure I agree with that. Every initializer in a class should work correctly. An external caller can initialize a class by calling any of its init methods, why can't a subclass? At the very least, NSWindowController's choice of designated initializer increases the burden on subclasses. -- Rick Mann rm...@latencyzero.com _______________________________________________ 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
