Docs for `Group` type

[Edwin van Leeuwen via Digitalmars-d-learn]

On Tuesday, 12 July 2016 at 11:40:48 UTC, Bahman Movaqar wrote:
> On 07/12/2016 01:01 PM, Mike Parker wrote:
>> Do you have some sample code that shows the error?
>
> Yes.  I'm working on Stockman[1] a playground to learn D.
> In file `etl.d`, line 110 [2], if I change the line to
>     auto refInvoice = group[1].takeOne();
> the file will not compile.  I have attached the compile error 
> to this
> message.
>
> Thanks,

What does group.writeln; output? That should give you a good 
sense of what is going on.