Should alias this support implicit construction in function calls and return statements?

[Simen Kjaeraas]

On 2012-38-13 15:12, Adam D. Ruppe <destructionator at gmail.com> wrote:

> On Thursday, 13 December 2012 at 14:25:27 UTC, Simen Kjaeraas wrote:
>>     foo(b); // Cannot implicitly convert byte to bbyte.
>
> I think the way it is now is correct for alias this.. it is kinda like  
> implicitly casting to a base class. That's correct, but going to a  
> superclass isn't necessarily right. You might only want it to be one  
> way. Suppose you had something like this:
>
> struct SafeText {
>    string text;
>    alias this text;
> }
>
> Safe text should implicitly convert to plain string text, but it  
> shouldn't go the other way automatically.

But this is easily solved:

struct SafeText {
     string text;
     string get( ) @property {
         return text;
     }
     alias get this;
}

This is just as explicit as what you propose, and possible with what we
currently have.


>> A long time ago, when dinosaurs roamed the earth, walterandrei.pdf[5]  
>> suggested that opImplicitCastTo and opImplicitCastFrom take care of  
>> this conversion.
>
> A separate function or facility for implicit cast to might be ok though.


-- 
Simen