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Newsgroups: comp.lang.ada
Date: Mon, 11 Sep 2017 13:00:03 -0700 (PDT)
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Subject: Re: Type invariants and private extensions?
From: Egil H H <ehh.public@gmail.com>
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Xref: news.eternal-september.org comp.lang.ada:48012
Date: 2017-09-11T13:00:03-07:00
List-Id: <comp.lang.ada>

On Monday, September 11, 2017 at 9:51:35 PM UTC+2, Victor Porton wrote:
> As far as I understand, type invariants cannot be applied to types with 
> private extensions. Right?
> 
> It would be nice to create private extension types which would allow to use 
> them only when certain boolean function on the parent type returns True.
> 
> Is anything like this possible?
> 

You can already do
type Foo is tagged private
   with Type_Invariant'Class => Bar(Foo);

The Invariant will then be inherited by all derived types


-- 
~egilhh