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$\forall$$i$:Id, $T$:Type, ${\it ds}$:$x$:Id fp$\rightarrow$ Type, $P$:(State(${\it ds}$)$\rightarrow$$T$$\rightarrow$Prop).
\\[0ex]Normal($T$)
\\[0ex]$\Rightarrow$ Normal(${\it ds}$)
\\[0ex]$\Rightarrow$ ($\forall$$s$:State(${\it ds}$). Dec($\exists$$v$:$T$. $P$($s$,$v$)))
\\[0ex]$\Rightarrow$ $\vdash$${\it es}$.@$i$ \=Precondition for "a"(v)\+
\\[0ex]$P$ State(${\it ds}$) (v:$T$)
\-
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