restricted system commands enabled.
**lua-linebreak-filter.tex
(./lua-linebreak-filter.tex
LBF false prevdepth=131072 prevgraf=0 mode=1
Underfull \hbox (badness 10000) in paragraph at lines 22--22
[]\f Some
\hbox(6.83331+0.0)x100.0, direction TLT
.\localpar
..\localinterlinepenalty=0
..\localbrokenpenalty=0
..\localleftbox=null
..\localrightbox=null
.\hbox(0.0+0.0)x5.0, direction TLT
.\f S
.\f o
.\f m
.\f e
.\glue(\rightskip) 0.0
Underfull \hbox (badness 252) in paragraph at lines 22--22
\f words in a paragraph
\hbox(6.94444+1.94444)x100.0, glue set 1.36108, direction TLT
.\f w
.\kern-0.27779 (font)
.\f o
.\f r
.\f d
.\f s
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f i
.\f n
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f a
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f p
.\f a
.\f r
.\f a
.\f g
.\f r
.\f a
.\f p
.\f h
.\glue(\rightskip) 0.0
Underfull \hbox (badness 1997) in paragraph at lines 22--22
\f that will be broken.
\hbox(6.94444+0.0)x100.0, glue set 2.71664, direction TLT
.\f t
.\f h
.\f a
.\f t
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f w
.\f i
.\f l
.\f l
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f b
.\kern0.27779 (font)
.\f e
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f b
.\f r
.\f o
.\f k
.\kern-0.27779 (font)
.\f e
.\f n
.\f .
.\penalty 10000
.\glue(\parfillskip) 0.0
.\glue(\rightskip) 0.0
POST [0] [0]
### vertical mode entered at line 0
### current page:
\glue(\topskip) 0.0
\hbox(6.94444+0.0)x100.0, glue set 2.71664, direction TLT
.\f t
.\f h
.\f a
.\f t
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f w
.\f i
.\f l
.\f l
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f b
.\kern0.27779 (font)
.\f e
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f b
.\f r
.\f o
.\f k
.\kern-0.27779 (font)
.\f e
.\f n
.\f .
.\penalty 10000
.\glue(\parfillskip) 0.0
.\glue(\rightskip) 0.0
total height 6.94444
goal height 0.0
prevdepth 2.0
! OK.
l.23 \showlists
[0]
LBF false prevdepth=131072 prevgraf=0 mode=1
POST
> 2.0pt.
l.25 \showthe\prevdepth
\showthe\prevgraf
> 0.
l.25 \showthe\prevdepth \showthe\prevgraf
[0]
LBF true prevdepth=131072 prevgraf=0 mode=1
Underfull \hbox (badness 10000) in paragraph at lines 26--26
[]\f Some words
\hbox(6.94444+0.0)x100.0, glue set 25.78345, direction TLT
.\localpar
..\localinterlinepenalty=0
..\localbrokenpenalty=0
..\localleftbox=null
..\localrightbox=null
.\hbox(0.0+0.0)x5.0, direction TLT
.\f S
.\f o
.\f m
.\f e
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f w
.\kern-0.27779 (font)
.\f o
.\f r
.\f d
.\f s
.\penalty 10000
.\glue(\parfillskip) 0.0
.\glue(\rightskip) 0.0
POST math_shift
! \textfont1 is undefined (character 120).
l.26 \directlua{CASE = 6}Some words $$x$$
more words.\par
Somewhere in the math formula just ended, you used the
stated character from an undefined font family. For example,
plain TeX doesn't allow \it or \sl in subscripts. Proceed,
and I'll try to forget that I needed that character.
[0]
LBF false prevdepth=0 prevgraf=3 mode=1
Underfull \hbox (badness 10000) in paragraph at lines 26--26
\f more words.
\hbox(6.94444+0.0)x100.0, glue set 28.10013, direction TLT
.\localpar
..\localinterlinepenalty=0
..\localbrokenpenalty=0
..\localleftbox=null
..\localrightbox=null
.\f m
.\f o
.\f r
.\f e
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f w
.\kern-0.27779 (font)
.\f o
.\f r
.\f d
.\f s
.\f .
.\penalty 10000
.\glue(\parfillskip) 0.0
.\glue(\rightskip) 0.0
POST
### vertical mode entered at line 0
### current page:
\glue(\topskip) 0.0
\hbox(0.0+0.0)x0.0, shifted 50.0, direction TLT
\penalty 0
\glue(\belowdisplayskip) 0.0
\glue(\baselineskip) 5.05556
\hbox(6.94444+0.0)x100.0, glue set 28.10013, direction TLT
.\localpar
..\localinterlinepenalty=0
..\localbrokenpenalty=0
..\localleftbox=null
..\localrightbox=null
.\f m
.\f o
.\f r
.\f e
.\glue(\spaceskip) 3.33333 plus 1.66666 minus 1.11111
.\f w
.\kern-0.27779 (font)
.\f o
.\f r
.\f d
.\f s
.\f .
.\penalty 10000
.\glue(\parfillskip) 0.0
.\glue(\rightskip) 0.0
total height 12.0
goal height 0.0
prevdepth 0.0, prevgraf 3 lines
! OK.
l.27 \showlists
[0] [0]
LBF false prevdepth=0 prevgraf=0 mode=1
! Invalid linebreak_filter.
l.28 \directlua{CASE = 5}Some words.\par
A linebreaking routine should return a non-empty list of nodes
and at least one of those has to be a \hbox.
Sorry, I cannot recover from this.
! ==> Fatal error occurred, bad output DVI file produced!
Output written on lua-linebreak-filter.dvi (7 pages, 648 bytes).