Using instance variables with Modern Runtime

Question

I have several years of experience in Obj-c and Cocoa, but am just now getting back into it and the advances of Obj-C 2.0 etc.

I\'m trying to get my head around the

Answer 1

I'm relatively new to Obj-C (but not to programming) and have also been confused by this topic.

The aspect that worries me is that it seems to be relatively easy to inadvertently use the iVar instead of the property. For example writing:

myProp = someObject;

instead of

self.myProp = someObject;

Admittedly this is "user" error, but it's still seems quite easy to do accidentally in some code, and for a retained or atomic property it could presumably lead to problems.

Ideally I'd prefer to be able to get the runtime to apply some pattern to the property name when generating any iVar. E.g. always prefix them with "_".

In practice at the moment I'm doing this manually - explicitly declaring my ivars, and deliberately giving them different names from the properties. I use an old-style 'm' prefix, so if my property is "myProp", my iVar will be "mMyProp". Then I use @synthesize myProp = mMyProp to associate the two.

This is a bit clumsy I admit, and a bit of extra typing, but it seems worth it to me to be able to disambiguate a little bit more clearly in the code. Of course I can still get it wrong and type mMyProp = someObject, but I'm hoping that the 'm' prefix will alert me to my error.

It would feel much nicer if I could just declare the property and let the compiler/runtime do the rest, but when I have lots of code my gut instinct tells me that I'll make mistakes that way if I still have to follow manual rules for init/dealloc.

Of course there are also plenty of other things I can also do wrong...