XSLT - apply a template to call-template result

Question

Is it possible to apply a template to the result of a call-template?

For example, the xml and 2 xslt below.

index.xml:

Answer 1

Is there any way to apply a template to the result of in index.xsl?

Yes, this is called multi-pass processing. The only peculiarity is that in XSLT 1.0 you must apply the implementation-dependent xxx:node-set() extension function to any intermediate result, which in general will be of the infamous RTF (Result Tree Fragment) type and thus will need to be converted to a regular tree.

Here is a complete example of multi-pass processing (I am using xsl:apply-templates and not xsl:call-template, but you can freely modify this example to use named templates and xsl:call-template instead):

when this transformation is applied on the following XML document:

  01
  02
  03
  04
  05
  06
  07
  08
  09
  10

the wanted result ( the content of any num elements is doubled in the first pass, then squared in the second pass) is produced:

4
16
36
64
100
144
196
256
324
400

---

II. In XSLT 2.0

The RTF "type" was abolished, so it is much more easier to specify multi-pass processing, which becomes almost indistinguishable from functional composition, as the following equivalent transformation shows:

when this transformation is applied on the same XML document (above), the same correct result is produced:

4
16
36
64
100
144
196
256
324
400