DIP74: Reference Counted Class Objects

[Orvid King via Digitalmars-d]

 From the perspective of someone mostly indifferent to the support 
for it:

Why does DIP74 require the references to be counted on 
assignment? Shouldn't it be defined such that reference counting 
operations only need to occur when an unbalanced or escapable 
reference is created? This would eliminate a large number of the 
required references. As long as the reference count of an object 
is the same entering a function as when it leaves the function, 
there's no need to do a bunch of twiddling in the middle.

It also appears to me that the opAddRef in the examples is 
simpler than it should be. I believe it should be doing an 
`assert(_refs)` first, to ensure a valid state entering into the 
function.

Lastly, I believe it should be opReleaseRef rather than 
opRelease, simply to be explicit on what is being released.