draft proposal for ref counting in D

[Walter Bright]

Steven Schveighoffer wrote:

On Jun 25, 2013, at 9:31 PM, Michel Fortin wrote:

 > Le 25-juin-2013 à 17:20, Steven Schveighoffer a écrit :
 >
 >> I don't think the autoreleasepool is relying on convention, it's simply 
giving the compiler a way to elide careful tracking of temporaries' reference 
counts.
 >
 > Not at all. Autorelease pools were useful at a time before ARC so you 
wouldn't have to think of releasing manually every object called functions were 
returned to you. Instead, most functions would return autoreleased object and 
you'd only have to retain those objects you were storing elsewhere.

Having used MRC, I appreciate what autoreleasepool did, but I thought of it 
being also as a kind of blanket way to allow the compiler to remove extra 
retains/releases in ARC.

Is it not advantageous to release a whole pool of objects vs. releasing them 
individually during execution?  All releases and retains are atomic, so I 
figured one could do some optimization when it's all lumped together.

I find the autorelease pools very GC-like -- you don't have to worry who uses or 
forgets the reference, it's kept in memory until you don't need it.

Anyway, everything I know about Obj-C ARC I learned from my iOS 5 book :)  So 
don't take me as an expert.

-Steve