[luatex] [lltx] paragraph breaking in lua (node-ltp)

[Frank Mittelbach]

  Hans

> the two bugs are (were) in old-school tracing which is what i never use

and they can be circumvented how?

when I run Taco's example code:

\tracingparagraphs=1 \tracingonline=1

\starttext
\startparbuilder[basic]
This is a sample paragraph .... \par or more of them

\stopparbuilder
\stoptext

I get

Lua linebreak_filter failed, reverting to default on line 1

@firstpass
@secondpass
[][] []
@\par via @0 b=* p=-10000 d=*
@@1: line 1.3- t=0 -> @0

Lua linebreak_filter failed, reverting to default on line 1
etc

and when I put in more text such as

\startparbuilder[basic]
This is a sample paragraph This is a sample paragraph This is a sample 
paragraph This is a sample paragraph
This is a sample paragraph This is a sample paragraph This is a sample 
paragraph This is a sample paragraph
This is a sample paragraph This is a sample paragraph This is a sample 
paragraph This is a sample paragraph
This is a sample paragraph This is a sample paragraph This is a sample 
paragraph This is a sample paragraph
\stopparbuilder

I get

error: C:/texlive/2014/texmf-dist/tex/context/base/node-ltp.lua:3148: 
attempt to index local 'hlist' (a number value)


> the par builder code is pretty compatible (although it gives on purpose
> different but consistent results with hz .. the new hz code was
> prototyped this way) .. i still need to find a real application for it

for the parbuilder?

what I would be looking for is not so much a direct application but the 
ability to test out some additional breaking functionality, such as 
river detection and prevention

> fyi: the code is already kind of old and evolves stepwise into a
> pluggable framework (i reported on this several times in articles and
> status documents)

would look forward to it

thanks
frank