Selection set logic

[Jay R. Ashworth]

On Fri, May 09, 2008 at 12:49:12PM -0400, Nancy Palmquist wrote:
> Shane Gray wrote:
> > Selector Sentence:                                    
> > a and b or c                                          
> > 
> > I believe the selector sentence should evaluate the same as "(a and b) or c"
> > giving a result with all the branch codes from QL to SS as well as AA.  
> > 
> > It would however seem to evaluate the same as "a and (b or c)" giving a
> > result with only branch codes between QL and SS.  No AA.
> > 
> > I have confirmed this by actually putting the parentheses in for both
> > options.  Is it that the selector sentence doesn't follow order of
> > precedence?
> > 
> Selector sentence follows Boolean order if you do not use parenthesis.  It is 
> not LEFT to RIGHT.  I know this but I do not remember which is first AND or OR. 
> I know NOT would be applied first, then as I think AND would be
> applied second then OR last.
>
> Since my memory is always confused, I always use parenthesis to insure
> it does what I want.
>
> I hate to leave defaults that could have a different agenda than I do.
>
> In Conclusion, a and b or c is the same as (a and b) or c

Um, Nancy?  Shane, says, above, that no, it's not.

Cheers,
-- jra
-- 
Jay R. Ashworth                   Baylink                      jra at baylink.com
Designer                     The Things I Think                       RFC 2100
Ashworth & Associates     http://baylink.pitas.com                     '87 e24
St Petersburg FL USA      http://photo.imageinc.us             +1 727 647 1274

	     Those who cast the vote decide nothing.
	     Those who count the vote decide everything.
	       -- (Joseph Stalin)