Re: Base'Class is instance of Der1?

[Martin Krischik <martin@krischik.com>]

Martin Dowie wrote:

> Martin Krischik wrote:
>> Hi R
>> 
>> R wrote:
>> 
>> 
>>>Hello.
>>>
>>>I've got function which has a parameter of type Base'Class.
>>>
>>>well I have 3 derived tagged records and depending of what exactly is
>>>the parameter I have to cast it to a proper function.
>> 
>> 
>> Maybe you want a view rename instead of a cast:
>> 
>> http://en.wikibooks.org/wiki/Programming:Ada:Subtypes#Rename_View
> 
> Surely:
> 
> type Parent_Type is tagged null record;
> type Child_Type is tagged null record;
> 
> Child_Instance : Child_Type;
> Parent_View : Parent_Type'Class renames Parent_Type'Class (Child_Type);
> 
> Should be:
> 
> type Parent_Type is tagged null record;
> type Child_Type is new Parent_Type with null record;
> 
> Child_Instance : Child_Type;
> Parent_View : Parent_Type'Class renames Parent_Type'Class
> (Child_Instance);

Ups, you are right! But why did you not hit the [edit] button and corrected
it?

Martin
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