Re: Understanding Identity Transformations

The things that make you say "Hmmmmm"...
Thanks for speaking up... this sort of experience shared here is invaluable!

Karl



On Sat, 12 Feb 2005 22:21:18 +0100, Joris Gillis <roac@xxxxxxxxxx> wrote:
> Tempore 21:55:30, die 02/12/2005 AD, hinc in
> xsl-list@xxxxxxxxxxxxxxxxxxxxxx scripsit Karl Stubsjoen <kstubs@xxxxxxxxx>:
> 
> > Wow.. that is easy except that I do not understand your notice
> > explanation... the difference between your not( ... ) and your !=.
> 
> "@cat != 'BLUE'": will be true if the context node has a 'cat' attribute
> *and* if it has a 'cat' attribute not equal to 'BLUE'. So it's the same as
> "boolean(@cat) and not(@cat='BLUE')"
> 
> "not(@cat='BLUE')": will be true if the context node has no 'cat'
> attribute *or* if it has a 'cat' attribute not equal to 'BLUE'. So it's
> equal to "not(@cat) or not(@cat='BLUE')"
> 
> Wow... so much boolean logic that it doesn't seem logical anymore...
> 
> > So what is the difference then?  I don't get it.
> 
> The difference is that '!=' will work and 'not(...=...)' will not.
> Now don't ask me why:)
> The reason can probably found at http://www.w3.org/TR/xpath.html#booleans
> , but I know it rather from experience than from any documentation.
> 
> 
> regards,
> --
> Joris Gillis (http://www.ticalc.org/cgi-bin/acct-view.cgi?userid=38041)
> Gaudiam omnibus traderat W3C, nec vana fides