Appending to a dynamic array at specific offset

[renoX]

Joseph Bell Wrote:
[cut]
> This does work
> msg.length = 3;
> msg ~= data; // Effectively resize the array back to 3 and then append
> 
> I don't know how inefficient the above approach is.

Well if the new data is smaller than the old data, then it is an in place replacement otherwise there is a new allocation and a copy, but this is unavoidable.

You can check it by printing msg.ptr before and after (I've did the check before replying)

As for a better notation, sorry but I don't know enough D to answer.
renoX