RE: short-circuit control forms

[Wilhelm.Spickermann@t-online.de (Wilhelm Spickermann)]

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On 20-Jun-01 Beard, Frank wrote:
...
> It seems to me that the "and" and "or" should have been implemented
> in the short circuit form to begin with, instead of requiring 
> "and then" and "or else".  As soon as one of the conditions is FALSE
> for "and" or TRUE for "or", there is no need to check the remaining
> arguments.
...
But this would lead to programs using "and" where "and then" is required now
and using "or" where "or else" is required now. If you want to prove certain
conditions at a point of a program, it�s much easier if you can use the
rules of mathematical logic. I prefer the way Ada is now and I think that
everyone using "and then" or "or else" for efficiency reasons should write a
comment stating the reasons clearly.

Wilhelm