ChainImpl save method

[Steven Schveighoffer]

On Wed, 29 Dec 2010 15:26:25 -0500, Andrej Mitrovic <none at none.none> wrote:

> I'm having trouble understanding this code in std.range.chainImpl:
>
>         @property ChainImpl save()
>         {
>             auto result = ChainImpl();
>             foreach (i, Unused; R)
>             {
>                 result._input[i] = _input[i].save;
>             }
>             return result;
>         }
>
> Specifically, line 1559 which is:
> auto result = ChainImpl();
>
> Let me see if I got my hunch right:
>
> Is this simply instantiating another implementation of ChainImpl with  
> the same arguments? e.g. inside an already instantiated template with  
> ChainImpl(Range1, Range2), would ChainImpl() simply instantiate another  
> ChainImpl template with the same compile-time arguments? Of course, it  
> wouldn't copy any runtime values since this is all done at compile-time  
> and they don't exist yet.

Yes.  Inside a template, the name of the template is synonymous with the  
template instance being instantiated.

So for example:

struct S(T)
{
    void foo(){ S s; // this is of type S!T
    }
}

-Steve