[pmwiki-users] Problem with skin <!--function: syntax

[Ed W]

Hi

Can someone please give me an example of how to use this syntax in a
template:
     <!--function:SomeFunc-->

I tried some simple examples using pmwiki 2.2.0 and 2.2.1 and all I get
back is an empty string, eg

     <!--function:trim " asd df "-->

Grateful for any help

Ed W