Why splitter() doesn't work?

[Mehrdad]

On Sunday, 14 October 2012 at 23:01:02 UTC, Jonathan M Davis 
wrote:
> On Sunday, October 14, 2012 22:09:43 Peter Alexander wrote:
>> I wonder if a better design for splitter would automatically
>> allocate an array when the input range doesn't support slicing?
>
> We generally try and avoid any kind of allocation like that in 
> std.algorithm. We leave it up to the programmer to do that. 
> Otherwise, you'd end up with all kinds of invisible performance 
> hits. And it's doubly bad for anyone trying to avoid using the 
> GC.
>
> - Jonathan M Davis


Well, you don't need to automatically allocate anything.

As long as you require the input to be a forward range, you can 
simply iterate over it over and over again every time you want to 
return front(). AFAICT no need to store anything anywhere.