Hi,
I have already created a thread on the subject and Wolgang, Marco and Taco have replied but the userdata environment is not yet clear to me. I would like, if possible, to write a definition, a property or a theorem on the left and illustrate it in the right margin with an example. In the code below, the second example is on the second page and not next to the second definition.
Thanks.
Fabrice

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\

useMPlibrary[dum]

\setuppapersize[A4]

\mainlanguage
  [fr]

\setuppagenumbering
     [alternative=doublesided]

\setuplayout
  [width=12cm,
   rightmargin=60mm]
 

\setupenumerations
  [before={\blank},
   after={\blank},
   alternative=serried,
   distance=0.5em,
   title=yes,
   titleleft=,
   titleright=,
   titlestyle=normal,
   headcommand=\groupedcommand{}{.},
   numbercommand=\groupedcommand{}{},
   titlecommand=\groupedcommand{(}{)},  
   width=fit]

\defineenumeration
   [definition]
   [text=Définition,
    number=no,
    style=italic]

\defineenumeration
   [exemple]
   [text=Exemple,
    number=no,
    style=normal]

\definemargindata[marginfigure][inright]
\setupmargindata [marginfigure][command=\vbox,align=middle,stack=yes]

\defineuserdata [margintext] [alternative=margintext]

\defineuserdataalternative [margintext] [renderingsetup=userdata:margintext]

\startsetups [userdata:margintext]
  \margindata
    [inright]
    [
     style={\switchtobodyfont[10pt]},
     width=\rightmarginwidth,
     align={flushleft,broad}
    ]
    {\startexemple
     \getinlineuserdata
     \stopexemple}
  \stopsetups

\showframe
\starttext
\startchapter[title={First Chapter},ownnumber=1]
\startdefinition
 \input ward
\stopdefinition
\startuserdata [margintext]
  \input ward
\stopuserdata
\startdefinition
  \input ward
\stopdefinition
\startuserdata [margintext]
  \input knuth
\stopuserdata
\stopchapter
\stoptext

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