Hi Hans,
First, how do I get an insert's class/type from the "insert" nodes on the page? With LuaTeX, the insert's class/type is the same as the subtype of the "ins" nodes, but the subtype of the "insert" nodes is always zero in LuaMetaTeX, so I'm not sure how to get the class/type.
After playing around, I found that this is stored in "<insert node>.index". I'm able to write to this value just fine, but whenever I read it I get an error. This minimal example: \starttext \setbox999=\vbox{\hrule width 10pt height 10pt} \startluacode local insert = node.new("insert") local rule = tex.box[999].list insert.list = rule insert.index = 4 node.write(insert) \stopluacode \stoptext works perfectly, but this example: \startluacode local insert = node.new "insert" insert.index = 4 print(insert.index) \stopluacode gives this error message: In \insertmode 2 you can't use zero as index. I suspect that this is a bug, but I may just be doing something wrong.
Indeed, we don't use these boxes and registers because we run in \insertmode=2. This gives us more state info (i kept the old method around for now).
Inserts always felt a little hacky in TeX, so I think that the new methods are a huge improvement.
Second, how do I get the head of the insert box from Lua? With LuaTeX, from TeX you would use "\box<class>" and from Lua you can use "tex.box[<class>]". With LuaMetaTeX, you use "\insertbox<class>" from TeX, but I'm not sure how to get at the insert box from Lua.
tex.getinsertdistance tex.getinsertmultiplier tex.getinsertlimit tex.getinsertheight tex.getinsertdepth tex.getinsertwidth tex.getinsertcontent tex.setinsertdistance tex.setinsertmultiplier tex.setinsertlimit tex.setinsertcontent
Perfect! "tex.getinsertcontent" does exactly what I need. Really minor, but I would expect that tex.insertcontent[4] = <some node> <some node> = tex.insertcontent[4] would be exist and be equivalent to <some node> = tex.getinsertcontent(4) tex.setinsertcontent(4, <some node>)
The insert (etc) handler is more clever and flexible. So, for instance we can bubble up inserts. I think you do a preroll so in that case you can set the migrations related parameter to not bubble up.
\starttext
\holdingmigrations\numexpr1+2+4\relax
\setbox0\hbox{test \footnote{test} test}
\setbox2\vbox{\unhcopy0}
\holdingmigrations0
\setbox4\vbox{\unhcopy0}
\unhbox0
\unvbox2
\unvbox4
\stoptext
But I have no clue how all that will work out with (lua) code that manipulates these things. In list nodes you can consult the pre and post fields to what got migrated.
I don't think that that will work in this case. I'm doing most of the work in "pre_output_filter", which is after all of the insert nodes have been removed from the page and put into their respective boxes. And I can't postpone setting any inserts until then because TeX needs to know their height for when it breaks the page. I don't really like how I have to move the footnotes, but I can't find any better way of doing things. If you're curious, most of the insert code is in these two functions: https://github.com/gucci-on-fleek/lua-widow-control/blob/2bca90/source/lua-w... https://github.com/gucci-on-fleek/lua-widow-control/blob/2bca90/source/lua-w... Thanks, -- Max