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From: Matthew Heaney <matthew_heaney@acm.org>
Subject: Re: Expressive Case Statements (was: Software landmines)
Date: 1998/09/02
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NNTP-Posting-Date: Wed, 02 Sep 1998 01:14:51 PDT
Newsgroups: comp.lang.ada
Date: 1998-09-02T00:00:00+00:00
List-Id: <comp.lang.ada>

tmoran@bix.com (Tom Moran) writes:

> Are the conditions in such a decision table always boolean, or might
> they be any enumerated type?

They can be any enumerated type.  For example, if color = (red, green,
blue), and boolean = (true, false), and that's 6 combinations:

color  R  R  G  G  B  B

bool   T  F  T  F  T  F

> Do you care if the compiler checks that you have branches for all
> possibilities (as in a case statement, but not in an elsif list)?

I find that it's better to consider all the _possible_ combinations,
then prune away the ones that don't make sense.  (See my other post for
a decision table analysis of a loop predicate.)