[OT] Finding longest documents

[Andrei Alexandrescu]

Sergey Gromov wrote:
> Wed, 15 Oct 2008 09:49:08 -0500,
> Andrei Alexandrescu wrote:
>> Sergey Gromov wrote:
>>> Wed, 15 Oct 2008 09:17:57 -0500,
>>> Andrei Alexandrescu wrote:
>>>> I see how it breaks those conventions, but I've never heard of them. The
>>>> convention I heard of is that if you want dynamic polymorphism you use
>>>> classes, otherwise you don't.
>>> How about if you want pass-by-value you use structs, otherwise you don't?  
>>> My argument against structs-collections is that I want to toss 
>>> collections around and build other collections out of them without 
>>> messing with pointers.
>> A struct can choose to implement value or reference semantics as it 
>> pleases. The only thing it can't readily implement is dynamic polymorphism.
> 
> I can imagine the documentation: "Ignore the fact it's a struct, it's 
> actually a reference internally."

No. "Don't submit to the dogma that struct == value semantics, because 
that was never true".

> So how do I return it?  Should I 
> return it by value, hoping that the implied reference semantics will stay 
> that way in future releases?  How does your Array!() behave?

That's not finished, but e.g. Appender can be copied around and always 
refers to the same underlying array.


Andrei