`clear`ing a dynamic array

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I'm afraid what you're asking for is impossible. Because 'a' and 
'b' are both slices, they each have their own 'length' field. 
When you do 'a = []', you're effectively doing 'a.length = 0'. 
There's no way to change 'b.length' through 'a'. To get that 
effect, you'd have to do something like this:
	int[] a = [1,2,3,4,5];
	int[]* b = &a;
	a = [];
	assert(*b == [] && b.length == 0);

On Saturday, 24 October 2015 at 13:18:26 UTC, Shriramana Sharma 
wrote:
> Hello. I had first expected that dynamic arrays (slices) would 
> provide a `.clear()` method but they don't seem to. Obviously I 
> can always effectively clear an array by assigning an empty 
> array to it, but this has unwanted consequences that `[]` 
> actually seems to allocate a new dynamic array and any other 
> identifiers initially pointing to the same array will still 
> show the old contents and thus it would no longer test true for 
> `is` with this array. See the following code:
>
> import std.stdio;
> void main()
> {
>   int a[] = [1,2,3,4,5];
>   int b[] = a;
>   writeln(a);
>   writeln(b);
>   //a.clear();
>   a = [];
>   writeln(a);
>   writeln(b);
> }
>
> which outputs:
>
> [1, 2, 3, 4, 5]
> [1, 2, 3, 4, 5]
> []
> [1, 2, 3, 4, 5]
>
> How to make it so that after clearing `a`, `b` will also point 
> to the same empty array? IOW the desired output is:
>
> [1, 2, 3, 4, 5]
> [1, 2, 3, 4, 5]
> []
> []
>
> ... and any further items added to `a` should also reflect in 
> `b`.