Re: Return by reference

[Brian Rogoff <bpr@shell5.ba.best.com>]

On 3 Nov 1999, Lutz Donnerhacke wrote:
> * Brian Rogoff wrote:
> >In any case, in response to Lutz Donnerhack, who wonders why I might want
> 
> 'Donnerhacke' (= 'thunder & hoe') please. Today exaktly seven guys with this
> surname live on this earth. 'Donnerhack' is much more common (something like
> 'Smith' ;-)).

My apologies.

> >to do such a thing, consider the problem of trying to write a printf like
> >like formatting library in Ada. One interface (proposed in the programming
> >FAQ at adahome) goes something like this
> >
> >    type Format_Type is limited private;
> >
> >    function  Format(S : in String) return Format_Type;
> >    procedure Printf    (Fmt : in Format_Type);
> >    function "&" (Fmt : in Format_Type; S : in String)    return Format_Type;
> >    function "&" (Fmt : in Format_Type; I : in Integer)   return Format_Type;
> >
> >etc.
> >
> >I was going to use the "Rosen trick" to modify data in the Fmt each time 
> >"&" is called. Unfortunately, that requires making the full view of
> >Format_Type limited and you run into the problem I described. 
> >
> >Is there a cleaner way to implement that interface? 
> 
> To my first and ignorant view it should work fine with an unlimited type.
> I implemented it for myself to check this view. Your will get it by E-Mail.

Thanks for the code, but I already know how to do this with a type whose 
public view is limited and its private view, not limited. I was wondering
if I can do this entirely with minimal potential copying.

-- Brian