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Subject: Re: Possible Ada deficiency?
Newsgroups: comp.lang.ada
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From: "Ed Falis" <falis@verizon.net>
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Date: Sun, 02 Jan 2005 00:36:01 GMT
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Date: 2005-01-02T00:36:01+00:00
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On 1 Jan 2005 11:43:15 -0800, <danmcleran@hotmail.com> wrote:

>
> package Some_Package is
> --public area
> type Secret_Type is concealed;
>
> procedure Print_Secret_Value (Value : in Secret_Type);
>
> private
> --Child packages can see here
> procedure Change_Concealed_Value (New_Value : in Secret_Type);
> concealed
> --Child packages cannot see here, they must use the public and/or
> private interface
> type Secret_Type is record
> Secret_Value : Integer;
> end record
> end Some_Package;
>

Why is this so much preferable to:

package Some_Package is
    type Public_Handle is private;

    procedure Print_Secret_Value (Value : in Public_Handle);

private
    procedure Change_Concealed_Value (New_Value : in Public_Handle);

    type Secret_Type;
    type Public_Handle is access all Secret_Type;
end Some_Package;

package body Some_Package is
    type Secret_Type is record
       Secret_Value : Integer;
    end record;

    ...

end Some_Package;

...?

- Ed