I don't like slices in D

[qznc]

On Thursday, 17 October 2013 at 18:41:53 UTC, Vitali wrote:
> The use case is:
>
> void removeElement(ref int[] arr, int index) {
>   arr = arr[0..index] ~ arr[index+1..$];
> }

The meaning of this code is: Create a new array out of composing 
two slices and assign it to arr. Of course, there is allocation 
happening.

What you probably want is: Move arr elements index+1..$ to 
index..$-1 and decrease length by one, preserving capacity. You 
can use std.algorithm.remove, which does move part. Hence:

import std.algorithm: remove;
void removeElement(ref int[] arr, int index) {
   remove(arr,index);
   arr.length--;
}