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From: Harald Schmidt <office@anobject.net>
Newsgroups: comp.lang.ada
Subject: How to define an array of a variant record type?
Date: Mon, 17 Nov 2003 17:57:00 +0100
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Date: 2003-11-17T17:57:00+01:00
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Hi,

I would like to define an array, which its element type is a variant record
and the Value_Type is only known at runtime.

   type Name_Value_Type is (String_Type,
                            Integer_Type,
                            Float_Type);

   type Name_Value(Value_Type : Name_Value_Type) is
      record
         The_Name : Unbounded_String;
         case Value_Type is
            when String_Type =>
               String_Value : Unbounded_String;
            when Integer_Type =>
               Integer_Value : Integer;
            when Float_Type =>
               The_Value : Float;
         end case;
      end record;

   type Name_Value_Sequence is array(Natural range <>) of Name_Value;

The compiler says "unconstrained element type in array declaration",
...right!

I know Ada is a strong typed language, but sometimes information is only at
runtime available. Does anyone know some workaround, or a regulare design
pattern for this problem?

Harald