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Date: Fri, 04 Jan 2002 12:32:35 -0500
From: Hyman Rosen <hyrosen@mail.com>
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Subject: Re: A case where Ada defaults to unsafe?
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Date: 2002-01-04T12:32:35-05:00
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Robert Dewar wrote:

> Well any vaguely competent Ada programmer should equally
> well know that in Ada "and then" and "or else" short circuit

 > and "and" and "or" do not.

Sure. But what do you gain from the non-short-circuit ones,
except for the risk that you've used them incorrectly?


> Exactly the same as in C, where you use either & or &&.


In C, you cannot use & and | in the same way that you use
&& and ||, because the former accept only integer operands.
For example, if you have a pair of pointers, p and q, and
wish to test whether both are not null, you must use p&&q.
If you were to use p&q, the compiler would reject it.

C++ does have the horrible trap that user-defined && and ||
operators don't short-circuit. Expert advice is to never
define these except in the rarest of circumstances.