Re: [boost] Re: Optional, tie, and iterator_adaptor

From: Joel de Guzman (djowel_at_[hidden])
Date: 2003-08-31 04:06:12

Joel de Guzman <djowel_at_[hidden]> wrote:

> IMO, this is better:
> 
>     optional<int> x;
>      if (x == none)
>         foo(x);

I meant:

    optional<int> x;
     if (x != none)  
        foo(x);

Of course. And following Brian's example:

   if (o != none)
      do_something(o);
   else
      maybe_do_other();

> Although I don't see this as problematic:
> 
>     optional<int> x;
>      if (x)
>         foo(x);
> 
> Or perhaps:
> 
>     optional<int> x;
>      if (!!x)
>         foo(x);
> 
> We already have an implicit conversion to safe_bool and an
> operator ! anyway. Keep it. There's nothing wrong with it:
> 
>     operator unspecified-bool-type() const;
>     bool operator!() const;
> 
> Perhaps it's just me, but I really dislike the * syntax. Why make optional
> pretend that it is a pointer when it's clearly not! Then, we go on and give
> it value semantics! C'mon!

-- 
Joel de Guzman
http://www.boost-consulting.com
http://spirit.sf.net