Stack-allocated arrays

[Janderson]

Dave wrote:
>> I'd love for "scope foo = new T[len];" to do for arrays what "scope 
>> bar = new Class;" does for classes. And indeed, if it's too big the 
>> compiler
> 
> I'm surprised it doesn't and see that as a bit inconsistent, with the 
> only serious argument against it being that 'scope' couldn't be used for 
> large dynamic arrays.
> 
> But then again:
> 
> class C
> {
>   int[264_000] a;
> }
> 
> void foo()
> {
>    scope C c = new C;
>    ...
> }
> 
> could also overflow the stack. In either case the work-around would be 
> the same (increase the stack size or not use 'scope').
> 

As a work around, I imagine it would be possible to write a template 
that used the above syntax with a static if that would change depending 
on the size:  Something like this (untested):


class FastArray(T, int size)
	if (size < 1000)
{
	T[size] a;
	... Overload operators
}

class FastArray(T, int size)
	if (size >= 1000)
{
	T a[] = new T[size];
	... Overload operators
}


//Use

void foo()
{
	scope FastArray array = new FastArray!(int, 10); //Stack
	scope FastArray array = new FastArray!(int, 10000); //Heap
}

Of course you never know where you are in the stack, so nesting these to 
much would be bad.