why use string for this example of appender?

[ludo]

Thank Steve,
I open a new thread with some corrections, better title, etc.

On Wednesday, 31 March 2021 at 22:05:12 UTC, Steven Schveighoffer 
wrote:
> On 3/31/21 5:32 PM, ludo wrote:
>> [...]
>
> ArrayBuilder should be similar in performance to Appender. I 
> think part of the issue with appender could be the ref counted 
> design. Only 1000 elements is going to show heavily the 
> setup/teardown time of allocation of the implementation struct. 
> But that is a guess. You may want to up the repetition count to 
> 100 or 1000.
>
> Note your code for appending with length is not doing what you 
> think:
>
> void concat_withLength()
> 		{
> 			int[] array;
> 			array.length = 1000;
> 			for (int j=0; j<1000; j++)
> 				array ~= j;
> 		}
>
> This allocates 1000 elements, and then append 1000 *more* 
> elements.
>
> I think you meant in the loop:
>
> array[j] = j;
>
> This should be the fastest one.
>
> -Steve