[hamstergene]

ARC is a tradeoff between manual and automatic memory management. Requring a little bit more care from programmer is intentional, not a disadvantage as you picture it, it is a price for not having, you know, GC. GC is less error prone not for free but at the price of eating CPU and memory, which in the world of mobile devices equal less battery life, so it is quite desirable for iPhones and MacBooks software not to have it.

[pjmlp]

ARC is automatic memory management.

"The Garbage Collection Handbook", chapter 5

http://gchandbook.org/

[devsquid]

Yup but people love to argue over the small shit. Chris Lattner even refers to ARC as a form of GC.

[hamstergene]

Different approaches to memory management differ in extent of how much of programmer's job they automate.

Garbage collectors are fully automatic and rarely if ever require to mind anything; automatic RC does almost everything but requires programmer to analyze and annotate some things as 'weak'; manual RC requires a lot more programmer's effort while still technically being "automatic"; and manual memory management means the programmer does everything.

Automatic/manual is a scale, not a boolean yes/no, and the point is that ARC lies on it a bit closer to manual than garbage collectors.

[pjmlp]

The thing is, ARC is a garbage collection algorithm.

There isn't anything like ARC vs GC, that is layman knowledge and just wrong from CS point of view.

[hamstergene]

ARC is not an algorithm, it a language-level feature that generates retain/release calls automatically so that the programmer does not have to. Unlike GC systems where the resulting program does run an algorithm (and wastes CPU on that), with ARC the generated program is no different as if retain/release were written manually and runs no extra code.

[pjmlp]

That is an implementation detail of how a reference counting algorithm can be implemented.

[jblow]

If you're going to say that, then hand-coded memory allocation is just an implementation detail for a garbage collection algorithm.

True in some sense, but mostly useless. Come on.