...

I tried the following

-------------------------------------- \starttext \startluacode local OldPreLB

function MyPreLB(head,gc) ?texio.write_nl("########### Here I am!") ?OldPreLB(head,gc) end

OldPreLB = callback.find('pre_linebreak_filter') callback.register('pre_linebreak_filter',MyPreLB) \stopluacode

Test \stoptext --------------------------------------

but MyPreLB() is not called. What I am doing wrong here?

Hi Wolfgang,

see http://www.ntg.nl/pipermail/ntg-context/2010/047018.html

-- Best regards,

Li Yanrui (???)

I see!

From the info found there

there are two user hooks: tasks.appendaction("processors","before","modules.mine.whatever_a") tasks.appendaction("processors","after","modules.mine.whatever_b") ----------------------------------------- it is not clear for me how to use this. So it seems that the luatex reference is useless for a context user. Is there an other documentation on this? I have found an other mechanism in 'luat-cbk.lua' which offers a pair of functions 'callbacks.push()' and 'callbacks.pop()'. But I have not made any attempts to use them. Are they useable or are they disabled too? Wolfgang