Is assigning self.string = @"" on an @property that's (retain)'d proper?

A philosophical question, of sorts. Is it proper to assign a constant string to an @property that's (retained)? Or, should I do self.string = [NSString stringWithString:@""];

Is there a memory leak? What if it's overre开发者_Python百科leased?

It's a constant string, so does it behave the same way as an NSString object?

If the property is (assign) does that mean it will not be valid after the run loop?

---

Yes, it's fine. No matter which way you do it, the constant string will still be compiled into your program (because you have to use it in [NSString stringWithString:@""] anyway). Constant strings don't actually get retained/released, but the what matters is the semantics of it: you're assigning a string (which has a net +0 retainCount as far as you're concerned — you haven't alloced it, so you don't own it) to a property which will take ownership of it. If the property is (assign), then it may still work with a constant string, but it will be semantically invalid after the autorelease pool drains.