Generic and fundamental language design issue

[Tommi]

On Sunday, 4 November 2012 at 17:41:17 UTC, Andrei Alexandrescu 
wrote:
>
> I don't think that claim is valid. As a simple example, 
> polymorphism requires indirection (due to variations in size of 
> the dynamic type compared to the static type) and indirection 
> is strongly correlated with dynamic allocation.

Sure, there are situations where heap allocation is always 
needed. But couldn't the question of "whether to heap or stack 
allocate" be considered just an implementation detail of the 
language. And hide that implementation detail so that the 
programmer doesn't even need to know what the words heap and 
stack mean.

I mean, wouldn't it be theoretically possible to sometimes even 
let the compiler allocate class objects in D from the stack, if 
the compiler can see that it's safe to do so (if that variable's 
exact type is known at compile time and never changes).