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From: "Jeffrey R. Carter" <jrcarter@acm.org>
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Subject: Re: Hiding details and protected types
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Date: 2007-04-24T19:16:17+00:00
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Maciej Sobczak wrote:
> 
> It is not possible to declare this type in the private part of the 
> protected type (why?), so it has to be declared outside PT:
> 
> type T is ...;
> protected type PT is
>   procedure P;
> private
>   A : T;
> end PT;
> 
> The problem is that declaring T in the same declaration scope pollutes 
> the name space and is against Good Engineering Principles (tm).

I agree. You can't hide the existence of T, but you can usually hide its 
details:

    type T is private;

    protected type P is
       ...
private
    type T is ...;

-- 
Jeff Carter
"Beyond 100,000 lines of code you
should probably be coding in Ada."
P. J. Plauger
26