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Date: 11 Sep 93 23:23:54 GMT
From: cs.utexas.edu!utnut!utcsri!csri.toronto.edu!blaak@uunet.uu.net  (Raymond 
Blaak)
Subject: thoughts on "holey" enumerated types
Message-ID: <1993Sep11.192353.19703@jarvis.csri.toronto.edu>
List-Id: <comp.lang.ada>

The thread on converting integers to a sparse enumerated type has got
me thinking.

Couldn't enumerated types always be implemented as a contiguous range, such
that use clauses to specify member ``positions'' just affected the 'POS and
'VAL functions?

That way enumerated type operations (especially loop traversal over a range,
or array indexing) can always be efficient. The only time one needs to know a
member's position is when converting to an integer. Using 'POS and 'VAL seems
safer than unchecked_conversion in these cases anyway.

Ray
blaak@csri.toronto.edu