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Date: Thu, 03 Jan 2002 15:29:32 -0500
From: Hyman Rosen <hyrosen@mail.com>
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Subject: A case where Ada defaults to unsafe?
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Date: 2002-01-03T15:29:32-05:00
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The conventional belief (at least on CLA :-) is that one of the
main distinctions between Ada and C/C++ is that Ada defaults to
safe behavior and C/C++ defaults to unsafe behavior (eg., array
indexing, automatic type conversions, and overflow checking).

It occurs to me that there is a case where the opposite seems to
be true. In C/C++, the && and || binary operators short-circuit,
evaluating their right operand only if necessary. In Ada, it is
necessary to specify "and then" and "or else" for this behavior,
otherwise the order of evaluation of the two sides is unspecified
if the simple "and" and "or" forms are used.

So in Ada, one could say 'if a /= 0 and b/a > 3' and fall into a
trap that would not happen in C/C++. Discuss?