I don't like slices in D

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On Thursday, 17 October 2013 at 18:00:20 UTC, Vitali wrote:
> I expected slices to be in D (http://dlang.org/arrays.html) 
> like they are in Go 
> (http://blog.golang.org/go-slices-usage-and-internals). But 
> they are not.
>
> Why the array have to be reallocated after the length of a 
> slice is changed? It makes slices useless.
>
> Here a little example (it fails):
>
>   void testSlices() {
>     int[] dArr = [10, 11, 12];
>     int[] dSlice = dArr[0..2];
>     dSlice.length++;
>     assert(dArr[2]==dSlice[2]); // failure
>   }

As David Eagen said, your problem is that in D, dArr[0..2] is not 
inclusive, it's exclusive, so you get dArr[0] and dArr[1]. 
Changing it to dSlice = dArr[0..3] will work (or better, 
dArr[0..$]). However, there's something else going on here that's 
fishy:

void testSlices()
{
	int[] dArr = [10, 11, 12];
	int[] dSlice = dArr[0..2];
	writeln(dArr.ptr, " ", dArr.capacity, " ", dArr.length);
	writeln(dSlice.ptr, " ", dSlice.capacity, " ", dSlice.length);

	dSlice.length++;
	writeln(dSlice.ptr, " ", dSlice.capacity, " ", dSlice.length);

	writeln(dArr);
	writeln(dSlice);
}

4002DFF0 3 3
4002DFF0 0 2
4002DFE0 3 3
[10, 11, 12]
[10, 11, 0]

dSlice says that it has length 2, but accessing dSlice[2] does 
not produce a RangeError... Likewise, printing it out prints 3 
elements, not 2. This looks like a bug to me.