On 23 May 2006, <[EMAIL PROTECTED]> wrote:
> Original message from prad <[EMAIL PROTECTED]>:
>
> > suppose that you have 2 conditions A and B where B take a lot of
> > effort to determine (eg looking for a string match in a huge file).
> >
> > either A or B needs to be true before you can execute 'this'.
> >
> > the 2 if statements below are equivalent i think:
> >
> > if A or B:
> > do this
> >
> > if A:
> > do this
> > elseif B:
> > do this
> >
> > now, do they work the same way?
> >
>
> Both of these forms are equivalent only in languages which
> short-circuit Boolean expressions (not all language implement
> short-circuiting...). C/C++ both support this feature.
[...]
The only language I can think of that (1) does complete evaluations,
(2) is still in use today, and (3) has a significant amount of code
written in it, is Pascal. The Wirth-Jensen definition of Pascal
specified complete evaluations. The once popular Borland Pascal
implemented that as an option. Don't know about gpc.
Regards,
Liviu Daia
--
Dr. Liviu Daia http://www.imar.ro/~daia
