On 7/7/2022 3:15 AM, Max Chernoff via ntg-context wrote:
Hi,
With the latest upload, "tex.linebreak" doesn't return an "info" table.
When running this code:
\startluacode function test(head) local new_head, info = tex.linebreak(node.copylist(head))
print(head, type(head), info, type(info))
if info == nil then print "!!! info is nil !!!" end
return head end
nodes.tasks.appendaction("processors", "after", "test") \stopluacode
\starttext Hello! \stoptext
with the latest upload I get (also note the small typo in "rigthfill"):
luatex warning > linebreak: no [ leftinit | rightinit | leftfill | rigthfill] expected
2353 : par vmodepar> userdata nil nil !!! info is nil !!! 2299 : glue userskip> userdata nil nil !!! info is nil !!! but with live.contextgarden.net I get:
luatex warning > tex: left parfill skip is gone Underfull \hbox (badness 10000) in paragraph at lines 20--1
929 : par vmode_par> userdata table: 0x39a050f7000 table 1561 : glue userskip> userdata nil nil !!! info is nil !!!
This is because you need to pass a list that conforms to what the builder expects and the callback that you use doesn't do that for you (after all, it also gets hbox content). There is no 'callback sequence handler' for the par builder (currently i see no need for it, also given the extra overhead involved) but this what what you can do: \startluacode function builders.paragraphs.constructors.methods.preroll_a(head) local result, info = tex.linebreak(head) tex.prevdepth = info.prevdepth tex.prevgraf = info.prevgraf return result end function builders.paragraphs.constructors.methods.preroll_b(head) local result, info = tex.linebreak(nodes.nuts.copylist(head)) inspect(info) return true end \stopluacode \defineparbuilder[preroll_a] \defineparbuilder[preroll_b] \starttext \setmainparbuilder[default] \input tufte \par \input tufte \page \setmainparbuilder[preroll_a] \input tufte \par \input tufte \page \setmainparbuilder[preroll_b] \input tufte \par \input tufte \page \stoptext The tex.linebreak function gets the properly prepared paragraph and can handle it then. On the to do is a to add a 'prepare' helper that adds the mandate nodes (par fillers etc) but even then one has to be careful where linebreak hackery is applied. Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl -----------------------------------------------------------------