% taken/adapted from a question on the list

\definedelimitedtext[parenthesis]   [location=text]
\setupdelimitedtext [parenthesis:1] [left={(}, right={)}]
\setupdelimitedtext [parenthesis:2] [symcolor=red,symstyle=boldslanted,style=slanted, left={[}, right={]}]
\setupdelimitedtext [parenthesis:3] [symcolor=blue,symstyle=bold,style=normal, left={\{}, right={\}}]

\starttext
    \parenthesis{My outer layer \parenthesis{my inner layer \parenthesis{my innermost layer}}}
\stoptext
