\begin{tabbing}
Valtype($k$;${\it da}$;${\it din}$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$kindcase\=($k$\+
\\[0ex]; $a$.fpf{-}cap(${\it da}$;IdDeq;$a$;Top)
\\[0ex]; $l$,${\it tg}$.fpf{-}cap(${\it din}$;product{-}deq(IdLnk;Id;IdLnkDeq;IdDeq);$\langle$$l$$,\,$${\it tg}$$\rangle$;Top) )
\-
\end{tabbing}