search of a workaround

[Namespace]

On Friday, 8 February 2013 at 23:45:09 UTC, Namespace wrote:
> Thank you.
> But it looks ugly, and I dislike the use of such constructs for 
> such simple feature.
> But cool thing. :D I like the meta stuff of D. :)
>
> Other favorites?

Currently I think that Solutions #2 or Solution #5 are the best 
solutions.
But I have no Idea which of them are more performant.
Solution #5 will cause many heap allocations and Solution #2 
cause many many copies.
What would be the better choice?
I could of course wait for rvalue references. :D