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From: "M. A. Alves" <maa@borba.ncc.up.pt>
Newsgroups: comp.lang.ada
Subject: Why default values not taken?
Date: Tue, 12 Jun 2001 15:53:42 +0100 (WEST)
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Date: 2001-06-12T15:53:42+01:00

I want to create an object with only some components different from their
default values e.g.

  Contact_Person := new Text_Item'(Remark => US("name and email"));

where Text_Item inherits Remark from Input_Item and adds Text, both 
defaulting to Null_Unbounded_String:

  type Input_Item is tagged record
    Remark: Unbounded_String;
  end record;

  type Text_Item is new Input_Item with record
    Text: Unbounded_String;
  end record;

Of course I get the compile error "no value supplied for component Text".

But do I really have to supply values for all components?  What is the
best idiom here?

Thanks,

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