hxt pickling question

Hi,

Trying to understand how to write a document using a pickler but I can't make sense of the types.  

From the example:

     runX ( xunpickleDocument xpSeason
                               [ withValidate no
                               , withTrace 1
                               , withRemoveWS yes
                               , withPreserveComment no
                               ] "simple2.xml"
	     >>>  
	     processSeason
	     >>>  
	     xpickleDocument   xpSeason
                               [ withIndent yes
                               ] "new-simple2.xml"
	   )

So all I want to do is pickle a value directly instead of reading the value from a document.  I expected to do
something like:

runX (someHXTPicklingFunction myValue
      >>>  
      xpickleDocument ...)

but I can't seem to figure out what someHXTPicklingFunction should be, it's certainly nothing obvious
like pickleDoc, because that generates the wrong value.