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Diffstat (limited to 'doc/refman/RefMan-cic.tex')
-rw-r--r-- | doc/refman/RefMan-cic.tex | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/doc/refman/RefMan-cic.tex b/doc/refman/RefMan-cic.tex index f0046ffe6..ac62abbe5 100644 --- a/doc/refman/RefMan-cic.tex +++ b/doc/refman/RefMan-cic.tex @@ -353,9 +353,9 @@ be derived from the following rules. \item[Assum] \inference{\frac{\WTE{}{T}{s}~~~~s \in \Sort~~~~c \notin E} {\WF{E;c:T}{}}} \item[Ax] \index{Typing rules!Ax} -\inference{\frac{\WFE{\Gamma}}{\WTEG{\Prop}{\Type(p)}}~~~~~ -\frac{\WFE{\Gamma}}{\WTEG{\Set}{\Type(q)}}} -\inference{\frac{\WFE{\Gamma}~~~~i<j}{\WTEG{\Type(i)}{\Type(j)}}} +\inference{\frac{\WFE{\Gamma}}{\WTEG{\Prop}{\Type(1)}}~~~~~ +\frac{\WFE{\Gamma}}{\WTEG{\Set}{\Type(1)}}} +\inference{\frac{\WFE{\Gamma}}{\WTEG{\Type(i)}{\Type(i+1)}}} \item[Var]\index{Typing rules!Var} \inference{\frac{ \WFE{\Gamma}~~~~~(x:T) \in \Gamma~~\mbox{or}~~(x:=t:T) \in \Gamma~\mbox{for some $t$}}{\WTEG{x}{T}}} \item[Const] \index{Typing rules!Const} @@ -481,11 +481,13 @@ The convertibility relation allows introducing a new typing rule which says that two convertible well-formed types have the same inhabitants. +\section[Subtyping rules]{Subtyping rules\index{Subtyping rules} +\label{subtyping-rules}} + At the moment, we did not take into account one rule between universes which says that any term in a universe of index $i$ is also a term in the universe of index $i+1$ (this is the {\em cumulativity} rule of -{\CIC}). This property is included into the -conversion rule by extending the equivalence relation of +{\CIC}). This property extends the equivalence relation of convertibility into a {\em subtyping} relation inductively defined by: \begin{enumerate} \item if $\WTEGCONV{t}{u}$ then $\WTEGLECONV{t}{u}$, @@ -496,7 +498,7 @@ convertibility into a {\em subtyping} relation inductively defined by: \item if $\WTEGCONV{T}{U}$ and $\WTELECONV{\Gamma::(x:T)}{T'}{U'}$ then $\WTEGLECONV{\forall~x:T, T'}{\forall~x:U, U'}$. \end{enumerate} -The conversion rule is now exactly: +The conversion rule up to subtyping is now exactly: \begin{description}\label{Conv} \item[Conv]\index{Typing rules!Conv} |