% \enabletrackers[sorters.tests]

\starttext

Æsop\index{Æsop}
æsop\index{æsop}
aesop\index{aesop}
Aesop\index{Aesop}

\setuphead[subject][style=bold]

\subject{before} \placeregister[index][n=1,method=before]
\subject{after}  \placeregister[index][n=1,method=after]
\subject{first}  \placeregister[index][n=1,method=first]
\subject{last}   \placeregister[index][n=1,method=last]

\stoptext
