type of concatenated arrays

[Janice Caron]

On 11/7/07, Steven Schveighoffer <schveiguy at yahoo.com> wrote:

> Now, a2 is declared as a const(char)[] array, but I think it should be just
> a char[] array.  Why?  because the concat operator should have made a copy
> of the array with length +1 and added the \n character.  If this is the
> case, I should be able to do whatever I want with the copy.  Why does it
> have to be const?

Because of copy-on-write.

If b is the empty string, then (a ~ b) will evaluate to a. No copy need be made.