OpenEuphoria

Re: Match Question

• Posted by Michael J. Sabal <m_sabal at yahoo.com> Jan 17, 2007
• 510 views

don cole wrote:
> 
>    Hello Everybody,
> 
>   Suppose the code:
> 
> }}}
<eucode>
>   if match(q,"A") or match(q,"B") or match(q,"C") or match(q,"D") then
> </eucode>
{{{

>   And you hit on a "B", would Euphoria continue looking or would that be the
> end of it?
> 
>    If so, wouldn't be best to put the most likely scenario in the "A"
>    position?
> 
> Don Cole

This is a shortcutting feature that was introduced some years ago.  You are 
correct that if B is a hit, the whole expression is true, so the interpreter
won't bother evaluating anything else after that.  The same thing happens
with false conditions in a series of "and" expressions.  If you are reasonably
sure that "A" will happen say 40%, "B" 30%, "C" 20%, and "D" 10% (for example),
then putting "A" first will definitely improve the overall performance of 
your program.  Of course, YMMV depending on how often the conditions are
checked and how complicated the match expressions are.

Mike Sabal