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From: nebbe@lglsun.epfl.ch (Robb Nebbe)
Newsgroups: comp.lang.ada
Subject: Re: Ada.strings.bounded problems?
Date: 25 Jan 1995 10:25:52 GMT
Organization: Ecole Polytechnique Federale de Lausanne
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 <1995Jan19.124412@lglsun.epfl.ch> <3fmnc1$rns@watnews1.watson.ibm.com>
 <Mats.Weber-2301951656460001@mlma11.matrix.ch> <D2xAyz.6L2@world.std.com>
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Date: 1995-01-25T10:25:52+00:00
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In article <D2xAyz.6L2@world.std.com>, bobduff@world.std.com (Robert A Duff) writes:

A good coherent explanation of the problems associated allowing the
redefinition of operations on scalar types and not allowing them to
reemerge deleted.

|> 
|> We sidestepped all those issues by drawing the line in a different place
|> -- "=" composes properly for tagged types, and not for untagged types.
|> Arrays of tagged types don't automatically have "<", and you can't do
|> case statements on them, and so on.  In fact, "=" and "/=" are the
|> *only* predefined operators for tagged types, so it's not so
|> unreasonable to treat them specially.
|> 
|> - Bob

I don't see any particularly compelling reasons to prefere having
drawn the line between tagged and untagged types rather than record
and non-record types. Tucker touched on this subject in a post in
this same thread but he sort of glossed over it by saying that
making the distinction between tagged and untagged types is more
"natural".