\begin{tabbing}
ecl{-}kinds($x$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=ecl\_ind($x$;$k$,${\it test}$.$k$.nil;$a$,$b$,$A$,$B$.$A$ @ $B$;$a$,$b$,$A$,$B$.$A$ @ $B$;$a$,$b$,$A$,$B$.$A$\+
\\[0ex]@ $B$;$a$,$A$.$A$;$a$,$m$,$A$.$A$;$a$,$m$,$A$.$A$;$a$,$l$,$A$.$A$)
\-
\end{tabbing}