Ranges, constantly frustrating

[Tobias Pankrath]

On Tuesday, 11 February 2014 at 10:10:27 UTC, Regan Heath wrote:
> Things like this should "just work"..
>
> File input ...
>
> auto range = input.byLine();
> while(!range.empty)
> {
>   range.popFront();
>   foreach (i, line; range.take(4))  //Error: cannot infer 
> argument types
>   {
>     ..etc..
>   }
>   range.popFront();
> }
>
> Tried adding 'int' and 'char[]' or 'auto' .. no dice.
>
> Can someone explain why this fails, and if this is a permanent 
> or temporary limitation of D/MD.
>
> R
Is foreach(i, val; aggregate) even defined if aggr is not an 
array or associated array? It is not in the docs: 
http://dlang.org/statement#ForeachStatement