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From: Ludovic Brenta <ludovic@ludovic-brenta.org>
Newsgroups: comp.lang.ada
Subject: Re: Discriminants of tagged types
Date: Wed, 27 Oct 2010 23:23:56 +0200
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Maciej Sobczak writes on comp.lang.ada:
> Yannick Duchêne wrote:
>
>> > as non-limited tagged types are nonsense anyway.
>>
>> Why ?
>
> Because tagged types usually represent entities that are bound to some
> resources and copying them is somewhere between cumbersome and
> impossible. Communication channels, database connections, etc.

Funny, I usually do the exact opposite.

I usually represent these things with untagged limited types.  Why would
these objects need to be tagged?  Conversely, my tagged types do not
necessarily (or usually, for that matter) represent resources; they
represent data with behavior or GUI widgets.  They do not always have to
be limited but they have to be tagged.

-- 
Ludovic Brenta.