Sometimes it is required to have a vertical line between the columns of your columnset. This code draws MetaPost lines in the right place:
<texcodecontext source=yes>\setuppapersize[A5]
\startuseMPgraphic{verticalrule}
if CurrentColumn < NOfColumns :
[\useMPgraphic{verticalrule}]
\definecolumnset [exampleTwoColumns] [n=2, background=verticalrule]
\starttext
\startcolumnset [exampleTwoColumns] \startlines % enforce line breaksStarlight, star bright,first star I see tonight;\dorecurse{4}{stoplines \input knuth}column \startlinesI wish I may, I wish I mighthave the wish I wish tonight.\stoplines \stopcolumnset
\stoptext
</texcodecontext>
=Streams=