\definefiller[dots][left=\dontleavehmode, right=\hskip\ZeroPoint\par]
\starttext
\dorecurse{4}{\filler[dots]}
\stoptext
fab@debian:~$ source context/tex/setuptex
Setting "/home/fab/context/tex" as ConTeXt root.
fab@debian:~$ context ntg19.tex
resolvers | trees | analyzing 'home:texmf'
mtx-context | run 1: luatex --fmt="/home/fab/context/tex/texmf-cache/luatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/formats/luatex/cont-en" --jobname="ntg19" --lua="/home/fab/context/tex/texmf-cache/luatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/formats/luatex/cont-en.lui" --no-parse-first-line --c:currentrun=1 --c:fulljobname="./ntg19.tex" --c:input="./ntg19.tex" --c:kindofrun=1 --c:maxnofruns=8 "cont-yes.mkiv"
This is LuaTeX, Version beta-0.80.0 (TeX Live 2015/dev) (rev 5195)
\write18 enabled.
resolvers > trees > analyzing 'home:texmf'
open source > 1 > 1 > /home/fab/context/tex/texmf-context/tex/context/base/cont-yes.mkiv
ConTeXt ver: 2015.04.01 12:00 MKIV beta fmt: 2015.4.3 int: english/english
system > 'cont-new.mkiv' loaded
open source > 2 > 2 > /home/fab/context/tex/texmf-context/tex/context/base/cont-new.mkiv
close source > 2 > 2 > /home/fab/context/tex/texmf-context/tex/context/base/cont-new.mkiv
system > files > jobname 'ntg19', input './ntg19', result 'ntg19'
fonts > latin modern fonts are not preloaded
languages > language 'en' is active
open source > 2 > 3 > /home/fab/ntg19.tex
fonts > preloading latin modern fonts (second stage)
fonts > 'fallback modern-designsize rm 12pt' is loaded
tex error > error on line 3 in file /home/fab/ntg19.tex: ! Undefined control sequence
\166>dots:right ->\hskip \ZeroPoint
\par
\spac_fillers_indeed ...\fillerparameter \c!right
\relax \scratchdimen \fill...
\syst_helpers_recurse_indeed_yes ...curse_content
\syst_helpers_recurse_indeed
<to be read again>
{
<inserted text>
2
\syst_helpers_recurse_indeed ...the \innerrecurse
}{#2}
l.3 \dorecurse{4}{\filler[dots]}
1 \definefiller[dots][left=\dontleavehmode, right=\hskip\ZeroPoint\par]
2 \starttext
3 >> \dorecurse{4}{\filler[dots]}
4 \stoptext
5 %%% Local Variables:
6 %%% Mode: context
7 %%% End:
8
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