Need for (C++20) Contiguous Range

[Steven Schveighoffer]

On 10/8/20 11:45 AM, IGotD- wrote:
> On Thursday, 8 October 2020 at 14:45:47 UTC, Steven Schveighoffer wrote:
>>
>> We have arrays in D, there is no need to duplicate what C++ does 
>> because they don't have a real array type.
>>
>> In D, you would check if the range is a dynamic array, and then use 
>> ptr/length to deal with optimizations (I do this in iopipe).
>>
> 
> Just clarify, you mean that anything that is continuous memory can be 
> converted to a slice (as supposed to an array, even if the relationship 
> is somewhat ambiguous is D).

Yes. I have argued in the past 
(https://dlang.org/articles/d-array-article.html) that the "true" array 
type is hidden in the runtime, and that we should just call T[] a slice.

> 
> So if a type with continuous memory storage is converted to a slice, 
> will isDynamicArray!T also be valid for the slice?
> 
Yes.

I was going to post the code for isDynamicArray, but like many things in 
std.traits, it's needlessly complicated.

It should just be:

enum isDynamicArray(T) = is(T == U[], U);

-Steve