Good to know, but it wouldn't work anyway, because it's `uint`, when it's `size_t` that's the issue. And as for the allocation, we could actually be very inefficient here, and it wouldn't really matter, because this is throwing an `Error` which is almost certainly going to kill the program. So, while we don't want to be unnecessarily inefficient, there's not much point in worrying about allocations. We _are_ kind of stuck with them though, since a `string` needs to be allocated to be passed as the argument for `msg`, and we don't have a `format` function to avoid all of the concatenation to construct the message.