Re: Understanding Identity Transformations

>So which would you advise to solve the question?
> 
> "@cat and not(@cat='BLUE')"
> 
> or
> "@cat!='BLUE'"

(Almost) Never used != if one or both arguments is a node set. Even in those
cases where it does do what you want, you have to think so hard each
time to convince yourself that's what you mean, that it always ends uo
makin the stylesheet harder to debug later.

If A is a node set with two or more nodes that are not string-equal
then A != x is always true for any value of x. This is an entirely
logical result of the fact that infix operators so an "if exists" over
the whole node set, but it's so rarely what you want that I try to avoid
!= as much as possible.

David

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