Archive for November 23, 2014

Sunday, November 23, 2014

NSAtom, the True Object

Brian Webster:

In our case, if our method is returning a YES value, that will end up with a full value of 0x0000000000000001. If you try interpreting this value as an object, the runtime will think it is a tagged pointer, since the bottom bit is 1. OK then, so what kind of object is this exactly?


Ah, so it looks like, whether by design or by accident, no matter what message you send to NSAtom, it returns a value of 1.

Update (2015-01-17): There’s been further discussion of NSAtom on Twitter.