On 30/11/2010, at 9:09 PM, Michael Watson wrote: > this is not correct; there are more possibilities than 0 being returned. in > most situations, sending a message to nil does indeed yield a return value of > 0/nil. but that's not true all of the time:
But it is true probably more than 99% of the time (where I also mean 0 to mean nil object ref or a nulled data structure in accordance with the reference you cited). For the level of the questioner, it's a close enough approximation and there is no value in being so pedantic where it would confuse and worry more than it would enlighten. Lots of people new to Cocoa bring with them defensive coding from other languages such as C++ (like checking for nil before sending any message) and the point is that in most cases it's just not necessary. Returning nil from a class factory method if some condition is not met is therefore perfectly legitimate, even if the caller wasn't particularly expecting it - and that was what the OP was asking. --Graham _______________________________________________ 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: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
