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From: Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>
Newsgroups: comp.lang.ada
Subject: Re: class wide object in generic package
Date: 12 Jun 2002 13:33:41 -0400
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"Ehud Lamm" <mslamm@huji.ac.il> writes:

> It seems to me you want as a generic paramter any type that has the Eval
> operation.
> So you can define a parent type having this operation (say an abstract type
> called Evalable).
> Now you can define the generic
> 
> with Evalable_Pak;
> generic
>     type My_Evalable is new Evalable_Pak.Evalable with private;
> ....
> 
> My_Evalable will have a primitive Eval operation.

Yes, it will have an Eval operation, but that operation will _not_ be
visible in the generic body. The generic body does _not_ "read" the
package spec for Evalable_Pak. 

That's why you need the generic formal package parameter; then the
generic body _does_ see everything in the generic formal package spec.

> (Hope I am not making a fool of myself here. 

Asking real questions is always ok.

> I confess not compiling a real example.)

That would have been a good idea :).

-- 
-- Stephe