deleting items from 2d arrays

[Daniel Keep]

Sergey Gromov wrote:
> Fri, 14 Aug 2009 13:55:18 +1000, Daniel Keep wrote:
> 
>> void dropElement(T)(ref T[] arr, size_t i)
>> {
>>     assert( i < arr.length );
>>     arr[i] = arr[$-1];
>>     arr = arr[0..$-1];
>> }
> 
> I think it's important to erase the last element after the move to make
> sure no dangling references to unused data are left in a memory area you
> don't manage anymore:
> 
> | void dropElement(T)(ref T[] arr, size_t i)
> | {
> |     assert( i < arr.length );
> |     arr[i] = arr[$-1];
>     arr[$-1] = T.init;
> |     arr = arr[0..$-1];
> | }
> 
> This is a sad consequence of conservative garbage collection.

Excellent point; I forgot about that.