On Feb 27, 2013, at 1:12 PM, Brad O'Hearne <br...@bighillsoftware.com> wrote: > I have a need to construct an object with the possibility of an error taking > place and needing to return that error. While it would be nice to have a > clean init method that returned no errors, in this particular case, the error > belongs with init. I've been pondering two ways of doing this: > > 1. Just a modified init method, where it returns nil for the return value and > sets an error pointer like so: > > - (id)init:(NSError **)error; > { > self = [super init]; > > if (self) > { > if ([self operationThatMightFail:error]) > { > *error = nil; > } > else > { > return nil; > } > } > > return self; > } > > OR > > 2. Using a static method to perform the dirty work, and then encouraging the > caller only to use this method to init the class, like so: > > - (AThing *)athing:(NSError **)error; > { > AThing *a = [[AThing alloc] init]; > > if ([a operationThatMightFail:error]) > { > *error = nil; > } > else > { > return nil; > } > > return a; > } > > What is the recognized convention or design pattern for addressing this in > Objective C, or does it not really matter?
Overall, I think that a factory method is a better design than tying this to allocation/initialization. John. _______________________________________________ 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