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`.


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