Re: Dispatch on the result still does not work?

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Sat, 11 Jul 2009 18:50:42 +0100, Chris Moore wrote:

> Dmitry A. Kazakov wrote:
>> On Sat, 11 Jul 2009 12:09:57 +0100, Chris Moore wrote:
>> 
>>> Dmitry A. Kazakov wrote:
>>>> Considering this one:
>>>>
>>>> package P is
>>>>    type T is tagged null record;
>>>>    function Value return T;
>>>>       
>>>>    type S is new T with null record;
>>>>    function Value return S;
>>>> end P;
>>>>       
>>>> package body P is
>>>>    function Value return T is
>>>>    begin
>>>>       return (null record);
>>>>    end Value;
>>>>       
>>>>    function Value return S is
>>>>    begin
>>>>       return (T with null record);
>>>>    end Value;
>>>> end P;
>>>>
>>>> use P;
>>>>    
>>>>    X : T'Class := S'(Value);
>>>> begin
>>>>    X := Value; -- Ambiguous?
>>>>
>>>> I would expect it rather dispatching on the tag of X, i.e. selecting Value,
>>>> which returns S.
>>>>
>>> But X is of type T'Class.  Or did you mean X := X.Value;?
>> 
>> No. I meant function Value that has no arguments.
> 
> Then both versions of Value are in scope and return types that can be
> assigned to T'Class.  Sounds ambiguous to me.

It is, if you don't consider them dispatching, which was the question.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de