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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Subject: Re: Reading a C record from socket - chicken / egg problem - now
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wojtek@power.com.pl (Wojtek Narczynski) writes:

> Another question is: can I declare non-contiguous enumeration
> subtypes, or only range x..y?

Only ranges.

>... I've been unable to figure out how to
> declare non-contiguous subtype, so I guess this isn't allowable, but
> why?

Perhaps perceived compiler complexity?  Consider, for example, an array
indexed by such a subtype.

Also, the constraint-checking code could be rather slow for such a
subtype.  I don't find that to be a good argument, since too-slow checks
can always be suppressed.  But the original designers of Ada 83 tried to
avoid any kind of "costly" checking code.

I have often wanted this feature, too.  Not to index arrays,
but to use in case statements, for example.

- Bob