How to check if an apply-template filled variable is a string or (possibly) empty node in XSLT?

Question

I need a test for a variable which would evaluate to true in two cases:

• There is a string inside which contains any non white space characters
• There is any node (which can be possibly empty)

and the variable is filled with apply-template call result.

I tried

test="normalize-space($var)"

but this doesn't cover the empty tag possibility. I also tried simply this:

test="$var"

but this evaluate to true even for white space only strings.

By the way "$var/*" produces an error "Expression ...something I don't remember... node-set" which is I think because of apply-template variable instantiation.

Is there any (which means even multi level decision) solution for this?

EDIT: I forgot to say that it's for XSLT 1.0 and preferably without any exslt extensions or similar.

Answer 1

Hope this helps:

"string($variable)" will test true if the string has any characters in it, false if it equals ''.

http://www.dpawson.co.uk/xsl/sect2/N3328.html#d4474e64

Contains no child nodes: not(node())

Contains no text content: not(string(.))

Contains no text other than whitespace: not(normalize-space(.))

Contains nothing except comments: not(node()[not(self::comment())])

Answer 2

If you want to check whether a result tree fragment contains any child nodes then you need exsl:node-set e.g.

<xsl:if test="exsl:node-set($variable)/node()"
   xmlns:exsl="http://exslt.org/common"&gt;

Without that extension function (or a similar one your particular XSLT 1.0 processor offers) you can't perform that check.