[basex-talk] Why is $node/@attr != 'blue' false when $node is null?

The code below returns 'blue', but I was expecting 'not blue'. The class attribute on an empty node is null; null != blue. let $node := () return if($node/@class != 'blue') then 'not blue' else 'blue' -- France Baril Architecte documentaire / Documentation architect france.baril@architextus.com