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From: Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>
Newsgroups: comp.lang.ada
Subject: Re: Record type with check?
Date: 09 Jan 2001 17:12:01 -0500
Organization: NASA Goddard Space Flight Center
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Matthias Teege <matthias@mteege.de> writes:

> Moin,
> 
> ist there any way to build a record type like this: 
> 
> type Datum is
>    record
>       Var_A  : Integer;
>       Var_B  : Integer;
>    end record;
> 
> which guarantees that Var_B is bigger than Var_A?

This sounds like a homework problem, so I'll only give hints. If it's
not homework, please reply with more info on why you need this.

You cannot simply declare a type that has this property. But you can
write a package that declares an abstract data type that does enforce
this property. It must have a Create procedure that checks that A < B,
and access procedures that let clients access A and B.

-- 
-- Stephe