RFC: naming for FrontTransversal and Transversal ranges

[Andrei Alexandrescu]

Rainer Deyke wrote:
> Robert Jacques wrote:
>> RAII is all about stack allocation over heap allocation (or so I
>> thought). Ah, wikipedia has set me straight. Anyways, now for the simple
>> answer: you can't create D1 arrays with RAII types, I think. (Anyone
>> tried scope Foo[] foo?) Anyways, in D2, if I remember correctly there's
>> a bug where struct finilizers don't run if they're allocated on the
>> heap. But if you're using classes for RAII like you should, the GC will
>> run their finalizers just fine after the array dies. But this is an
>> seems to be an issue about the elements/values inside the containers,
>> not the container itself. So I'm lost.
> 
> A RAII variable is "destroyed" when it goes out of scope, where
> "destroyed" means that a destructor is called.  RAII is a transitive
> feature.  When a RAII variable is destroyed, its members are also
> destroyed.  When a RAII container is destroyed, all of its contents are
> destroyed.
> 
> References in D are not RAII types, because when a reference goes out of
> scope, the "contents" of that reference are not destroyed until the
> garbage decides to collect them, at which point it is too late to
> perform clean-up.
> 
> When an array dies, its contents are destroyed.  The issue is when the
> array dies.
> 
> If the array is a value type, the array dies when it goes out of scope,
> so RAII is possible.
> 
> If the array is a reference type, the array dies when the garbage
> collector decides to run sometime after all live references to the array
> have died, so RAII is not possible.

RAII can be implemented even with reference semantics. The mechanics 
would involve reference counting.

Andrei