RE: [xsl] syntax for passing variable into XPath statement

["Michael Kay" <mhk@xxxxxxxxx>]

You haven't shown us the variable declaration, but I suspect it is not a
number. Perhaps it is a result tree fragment. It would still look like a
number when you print it. Perhaps you declared it as

<xsl:variable name="n"><xsl:value-of select="3"/></xsl:variable>

(I'm doing a Jeni here, trying to debug code you haven't shown me: but the
above is a very common error.)

Either declare it in a way that makes it a number, e.g.

<xsl:variable name="n" select="3"/>

or convert it to a number at the point where it is used in a numeric
predicate

/a/b/c/d[number($n)]

The problem is that if you write a/b[$n] where $n isn't a number, it's
converted to a boolean, not to a number. Converting a result tree fragment
to a boolean always gives true, which means the predicate has no effect.

Michael Kay

> -----Original Message-----
> From: Esther_Strom@xxxxxxxx [mailto:Esther_Strom@xxxxxxxx] 
> Sent: 06 August 2004 18:21
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Subject: [xsl] syntax for passing variable into XPath statement
> 
> 
> 
> 
> 
> I'm pretty new at this, and haven't been able to find a 
> sample of what I'm
> trying to do. I have a variable set up, and it is getting set 
> correctly -
> I've got an fo:inline printing out the value of the variable 
> at each point
> in the code. But I need to pass that variable into an XPath 
> statement as a
> predicate (the variable is a number), and although it isn't 
> causing any
> errors the way it is now, I don't think it's getting set. 
> Could someone
> take a look and see if I'm doing something wrong?
> 
> * I know the variable navNum is set correctly because of the value-of
> statement inside the inline *
> <xsl:apply-templates select="Zone2"/>z2 is at navNum<fo:inline
> font-weight="bold"><xsl:value-of select="$navNum"/></fo:inline>
> 
> * now I need to pass that variable number into here to get the correct
> NavigationDivision element. If I hard-code a number in, the statement
> provides the correct output *
> <xsl:value-of
> select="//MLPublication/NavigationDivision[$navNum]/Activity/T
> itle[1]"/>
> 
> I know in cases where you're passing a variable into a parameter you
> enclose it in curly braces, but doing that causes my parser 
> to throw an
> error.
> |------------------------------|
> | E S T H E R  S T R O M, CLPP |
> | Notes Application Development|
> | McDougal Littell             |
> | 909 Davis Street             |
> | Evanston, IL 60201 USA       |
> | w: 847.424.3209              |
> | e: esther_strom@xxxxxxxx     |
> |------------------------------|