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From: tmoran@acm.org
Newsgroups: comp.lang.ada
Subject: Re: [OT] Best way to isolate a GUI?
References: <b2vuib$4q4$1@slb9.atl.mindspring.net>
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Date: 2003-02-20T08:26:25+00:00
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>Short of possibly efficiency concerns or representation issues, I just don't
>see much excuse for variant records when we've got tagged types.
  Whoa there!  If you have default discriminants, you can have
Transport : Vehicle(Kind=>Car, Horsepower=>100);
and later
  Transport := (Kind=>Truck, Axle_Count=>3, Capacity => Tons'(0.5));
and the compiler will even warn you if you forget and try:
  Transport := (Kind=>Truck, Capacity => Tons'(0.5));
That's a lot simpler than futzing with
  Transport : Vehicle_Ptr := new Car'(Horsepower=>100);
etc