Is it okay to call an init method in self, in an init method?

Question

Recently I realized I needed to add an argument to the init method for a helper class I've got. The helper class deals with alert views so it already has a bunch of arguments in the init, which are looked at, tweaked, and then sent on to the alert view.

Since I'm using the method as it is in various places, I don't want to risk crashing (by missing one of those places and getting an 'unrecognized selector' in the hands of a customer) so I decided to add a second init method.

I.e.

- (id)initWithA:B:C:D:

and

- (id)initWithA:B:C:foo:D:

Right now I've simply copy pasted the first one's implementation into the foo: one, but ideally what would be nice is making the first call the second, i.e.

- (id)initWithA:a B:b C:c D:d
{
    return [self initWithA:a B:b C:c foo:nil D:d];
}

but I'm not sure if this is acceptable or not. Code appears to be working fine.

Answer 1

Yes, that is perfectly acceptable and actually quite common.

This is why we have things called a "Designated Initializer". That's the initializer method to which all other initializers get redirected (usually).