On 02/05/18 03:17, Hans Hagen wrote:
On 5/1/2018 12:16 PM, Henri Menke wrote:
Dear list,

It seems as if the pre_output_filter only gives you the nodes in the
body block but without the \headline and \footline.  I would have
expected that those are included because \plainoutput performs

    \shipout\vbox{\makeheadline\pagebody\makefootline}

and I would have expected to get the vlist defined by the above \vbox
inside the callback.  Am I doing it wrong or am I using the wrong callback?
you can for instance use vpack_filter

But how do I detect whether what is being packed is the main vertical list? According the manual `groupcode` should be <empty> for the main vertical list but that just never happens. With the following MWE

    \directlua{
    callback.register("vpack_filter",
                      function(head,groupcode)
                          print('"' .. groupcode .. '"')
                          return head
                      end)
    }

    Hello World!

    \bye

I only see

"vbox"
"vbox"
"vbox"

in the log.



-----------------------------------------------------------------
                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
        tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-----------------------------------------------------------------

Reply via email to