Re: [Exist-open] Odd result from test case comparing a non-existingattribute with a value

[Michael B. <mbe...@mb...>]

Jonas Lundberg wrote:

> <xml>
> <base_eq>true</base_eq>
> <a>false</a>
> <b>false</b>
> <c>false</c>
> </xml>
>
> I am actually not sure whether the output is correct... but it doesn't
> feel right.

Unfortunately, or maybe not, processors don't much care whether things feel
right to humans.

Parts of the XPath/XQuery handling of Booleans derived from sequences could
well have come from Alice in Wonderland (whose author was indeed a pioneer
of formal logic).

So: let's first bring the variable binding syntax up to date my making
declare variable $node {( <lang direction="down"/>)};
into
declare variable $node :=  (<lang direction="down"/>);
and then hand over to our trusty referee Saxon 8, who tells us
<xml>
   <base_eq>true</base_eq>
   <a>false</a>
   <b>false</b>
   <c>false</c>
</xml>

...just as eXist does.

As ever, if you think eXist is wrong, try Saxon. If Saxon says the same
thing, as here, either re-ponder the specs or ask on xquery-talk. If you do,
Michael Kay will probably give you an answer himself.

Michael Beddow