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digitalmars.D.bugs - zero size static array behaviour "incongruous"

reply "Regan Heath" <regan netwin.co.nz> writes:
The behaviour of static and dynamic arrays is inconsistent here:

import std.stdio;

void main()
{
	int[0] s;
	int[ ] p = new int[0];
	
	writefln("%d %x",p.length,p.ptr);
	writefln("%d %x",s.length,s.ptr);
}

[Output]
0 0
0 12ff28

I would suggest that "int[0] s;" be an error, as it's pretty meaningless..  
Except template programmers would likely be a little annoyed with that.

I would suggest that "int[0] s;" have a null data pointer (as the dynamic  
one does), but I believe they're implemented in such a way that there is  
no such data pointer.

I hope Walter can see a good solution to this. Ideally they should behave  
the same I feel.

Regan
Jul 20 2005
parent "Regan Heath" <regan netwin.co.nz> writes:
On Thu, 21 Jul 2005 16:10:23 +1200, Regan Heath <regan netwin.co.nz> wrote:
 The behaviour of static and dynamic arrays is inconsistent here:

 import std.stdio;

 void main()
 {
 	int[0] s;
 	int[ ] p = new int[0];
 	
 	writefln("%d %x",p.length,p.ptr);
 	writefln("%d %x",s.length,s.ptr);
 }

 [Output]
 0 0
 0 12ff28

 I would suggest that "int[0] s;" be an error, as it's pretty  
 meaningless.. Except template programmers would likely be a little  
 annoyed with that.

 I would suggest that "int[0] s;" have a null data pointer (as the  
 dynamic one does), but I believe they're implemented in such a way that  
 there is no such data pointer.

 I hope Walter can see a good solution to this. Ideally they should  
 behave the same I feel.

I suspect the solution is to cause "new int[0]" to allocate a zero length item on the heap. Regan
Jul 20 2005