$\forall$${\it ds}$:$x$:Id fp$\rightarrow$ Type, ${\it da}$:$k$:Knd fp$\rightarrow$ Type, $x$:ecl(${\it ds}$;${\it da}$), $L$:event{-}info(${\it ds}$;${\it da}$) List.
\\[0ex]ecl{-}halt(${\it ds}$;${\it da}$;$x$)(0,$L$)
\\[0ex]$\Rightarrow$ isl(ecl{-}halt{-}kind($x$))
\\[0ex]$\Rightarrow$ 1of(last($L$)) $=$ outl(ecl{-}halt{-}kind($x$)) $\in$ Knd