\begin{tabbing}
R{-}links($A$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=case $A$ of \+
\\[0ex]Rnone =$>$ []
\\[0ex]Rplus(${\it left}$,${\it right}$)=$>$${\it rec}_{1}$,${\it rec}_{2}$.${\it rec}_{1}$ @ ${\it rec}_{2}$
\\[0ex]Rinit(${\it loc}$,$T$,$x$,$v$)=$>$ []
\\[0ex]Rframe(${\it loc}$,$T$,$x$,$L$)=$>$ []
\\[0ex]Rsframe(${\it lnk}$,${\it tag}$,$L$)=$>$ [${\it lnk}$]
\\[0ex]Reffect(${\it loc}$,${\it ds}$,${\it knd}$,$T$,$x$,$f$)=$>$ []
\\[0ex]Rsends(${\it ds}$,${\it knd}$,$T$,$l$,${\it dt}$,$g$)=$>$ [$l$]
\\[0ex]Rpre(${\it loc}$,${\it ds}$,$a$,$T$,$P$)=$>$ []
\\[0ex]Rkframe(${\it loc}$,$k$,$L$)=$>$ []
\\[0ex]Rksframe(${\it loc}$,$k$,$L$)=$>$ []
\\[0ex]Rrframe(${\it loc}$,$x$,$L$)=$>$ []
\-
\end{tabbing}