\begin{tabbing}
@$i$ events of kind $k$ change $x$ to $f$ State(${\it ds}$) (val:$T$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=($\forall$$x$:Id. vartype($i$;$x$) $\subseteq\rho$ ${\it ds}$($x$)?Top) \& kindtype($i$;$k$) $\subseteq\rho$ $T$\+
\\[0ex]\& $\forall$$e$@$i$. kind($e$) $=$ $k$ $\Rightarrow$ valtype($e$) $\subseteq\rho$ $T$ \& ($x$ after $e$) $=$ $f$((state when $e$),val($e$))
\-
\end{tabbing}