Re: [Exist-open] Function invokation with an empty argument fails in newer version of eXist

[Kemal P. <ke...@pa...>]

Ok, always good to see bugs fixed, at least it forces me to write correct
code :) But the thing is, putting a "?" was the first thing I tried:

*declare function local:buildLightXmlObjectList($results as element()*,
$scope as element()?, $hits-perpage as xs:integer, $hit-start as
xs:integer) as element() {*
*    do some stuff*
*};*

But now I got this error:

*ERROR XPTY0004: The actual cardinality for parameter 2 does not match the
cardinality declared in the function's signature:
result:buildResultListItem($result as element(), $scope as element())
element(). Expected cardinality: exactly one, got 0.*

Being no XQuery expert I always hesitate to declare something a bug, but
this does sound confusing to me. I mean, the "?" should denote "zero or
one", right? But it says that et expects exactly one...

2012/11/11 Wolfgang Meier <wol...@ex...>

> > I am sitting with some XQuery functions which I wrote last year and
> which use to run just fine in my eXist DB 1.4. Yesterday I built the latest
> version of eXist from the trunk and now I have a problem invoking the
> following function:
> >
> > declare function local:buildLightXmlObjectList($results as element()*,
> $scope as element(), $hits-perpage as xs:integer, $hit-start as xs:integer)
> as element() {
> > do some stuff
> > };
> >
> > The thing is, in some situations I call the function with an empty
> second argument, like this (i do handle the case when the argument is
> empty):
> The declaration $scope as element() requires exactly one element, so the
> XQuery engine must generate an error if you pass in the empty sequence.
> eXist-db 1.4.x allowed the empty sequence, but this was definitely a bug
> and I fixed this recently.
>
> Fixing your function declaration is easy - just add a ? to the declared
> type:
>
> $scope as element()?
>
> Wolfgang
>