On 5/1/2018 11:50 PM, Henri Menke wrote:
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

build_page_filter

-----------------------------------------------------------------
                                          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