diff -r 55497029b255 -r 7c638a46dcbb doc-src/TutorialI/CTL/document/PDL.tex --- a/doc-src/TutorialI/CTL/document/PDL.tex Wed Feb 02 18:06:00 2005 +0100 +++ b/doc-src/TutorialI/CTL/document/PDL.tex Wed Feb 02 18:06:25 2005 +0100 @@ -87,11 +87,9 @@ \isamarkuptrue% \isacommand{lemma}\ mono{\isacharunderscore}ef{\isacharcolon}\ {\isachardoublequote}mono{\isacharparenleft}{\isasymlambda}T{\isachardot}\ A\ {\isasymunion}\ {\isacharparenleft}M{\isasyminverse}\ {\isacharbackquote}{\isacharbackquote}\ T{\isacharparenright}{\isacharparenright}{\isachardoublequote}\isanewline \isamarkupfalse% -\isacommand{apply}{\isacharparenleft}rule\ monoI{\isacharparenright}\isanewline +\isamarkupfalse% \isamarkupfalse% -\isacommand{apply}\ blast\isanewline \isamarkupfalse% -\isacommand{done}\isamarkupfalse% % \begin{isamarkuptext}% \noindent @@ -101,112 +99,30 @@ \isamarkuptrue% \isacommand{lemma}\ EF{\isacharunderscore}lemma{\isacharcolon}\isanewline \ \ {\isachardoublequote}lfp{\isacharparenleft}{\isasymlambda}T{\isachardot}\ A\ {\isasymunion}\ {\isacharparenleft}M{\isasyminverse}\ {\isacharbackquote}{\isacharbackquote}\ T{\isacharparenright}{\isacharparenright}\ {\isacharequal}\ {\isacharbraceleft}s{\isachardot}\ {\isasymexists}t{\isachardot}\ {\isacharparenleft}s{\isacharcomma}t{\isacharparenright}\ {\isasymin}\ M\isactrlsup {\isacharasterisk}\ {\isasymand}\ t\ {\isasymin}\ A{\isacharbraceright}{\isachardoublequote}\isamarkupfalse% -% -\begin{isamarkuptxt}% -\noindent -The equality is proved in the canonical fashion by proving that each set -includes the other; the inclusion is shown pointwise:% -\end{isamarkuptxt}% \isamarkuptrue% -\isacommand{apply}{\isacharparenleft}rule\ equalityI{\isacharparenright}\isanewline -\ \isamarkupfalse% -\isacommand{apply}{\isacharparenleft}rule\ subsetI{\isacharparenright}\isanewline -\ \isamarkupfalse% -\isacommand{apply}{\isacharparenleft}simp{\isacharparenright}\isamarkupfalse% +\isamarkupfalse% +\isamarkupfalse% +\isamarkupfalse% \isamarkupfalse% -% -\begin{isamarkuptxt}% -\noindent -Simplification leaves us with the following first subgoal -\begin{isabelle}% -\ {\isadigit{1}}{\isachardot}\ {\isasymAnd}s{\isachardot}\ s\ {\isasymin}\ lfp\ {\isacharparenleft}{\isasymlambda}T{\isachardot}\ A\ {\isasymunion}\ M{\isasyminverse}\ {\isacharbackquote}{\isacharbackquote}\ T{\isacharparenright}\ {\isasymLongrightarrow}\ {\isasymexists}t{\isachardot}\ {\isacharparenleft}s{\isacharcomma}\ t{\isacharparenright}\ {\isasymin}\ M\isactrlsup {\isacharasterisk}\ {\isasymand}\ t\ {\isasymin}\ A% -\end{isabelle} -which is proved by \isa{lfp}-induction:% -\end{isamarkuptxt}% -\ \isamarkuptrue% -\isacommand{apply}{\isacharparenleft}erule\ lfp{\isacharunderscore}induct{\isacharparenright}\isanewline -\ \ \isamarkupfalse% -\isacommand{apply}{\isacharparenleft}rule\ mono{\isacharunderscore}ef{\isacharparenright}\isanewline -\ \isamarkupfalse% -\isacommand{apply}{\isacharparenleft}simp{\isacharparenright}\isamarkupfalse% -% -\begin{isamarkuptxt}% -\noindent -Having disposed of the monotonicity subgoal, -simplification leaves us with the following goal: -\begin{isabelle} -\ {\isadigit{1}}{\isachardot}\ {\isasymAnd}x{\isachardot}\ x\ {\isasymin}\ A\ {\isasymor}\isanewline -\ \ \ \ \ \ \ \ \ x\ {\isasymin}\ M{\isasyminverse}\ {\isacharbackquote}{\isacharbackquote}\ {\isacharparenleft}lfp\ {\isacharparenleft}\dots{\isacharparenright}\ {\isasyminter}\ {\isacharbraceleft}x{\isachardot}\ {\isasymexists}t{\isachardot}\ {\isacharparenleft}x{\isacharcomma}\ t{\isacharparenright}\ {\isasymin}\ M\isactrlsup {\isacharasterisk}\ {\isasymand}\ t\ {\isasymin}\ A{\isacharbraceright}{\isacharparenright}\isanewline -\ \ \ \ \ \ \ \ {\isasymLongrightarrow}\ {\isasymexists}t{\isachardot}\ {\isacharparenleft}x{\isacharcomma}\ t{\isacharparenright}\ {\isasymin}\ M\isactrlsup {\isacharasterisk}\ {\isasymand}\ t\ {\isasymin}\ A -\end{isabelle} -It is proved by \isa{blast}, using the transitivity of -\isa{M\isactrlsup {\isacharasterisk}}.% -\end{isamarkuptxt}% -\ \isamarkuptrue% -\isacommand{apply}{\isacharparenleft}blast\ intro{\isacharcolon}\ rtrancl{\isacharunderscore}trans{\isacharparenright}\isamarkupfalse% -% -\begin{isamarkuptxt}% -We now return to the second set inclusion subgoal, which is again proved -pointwise:% -\end{isamarkuptxt}% \isamarkuptrue% -\isacommand{apply}{\isacharparenleft}rule\ subsetI{\isacharparenright}\isanewline +\isamarkupfalse% +\isamarkupfalse% +\isamarkupfalse% +\isamarkuptrue% \isamarkupfalse% -\isacommand{apply}{\isacharparenleft}simp{\isacharcomma}\ clarify{\isacharparenright}\isamarkupfalse% -% -\begin{isamarkuptxt}% -\noindent -After simplification and clarification we are left with -\begin{isabelle}% -\ {\isadigit{1}}{\isachardot}\ {\isasymAnd}x\ t{\isachardot}\ {\isasymlbrakk}{\isacharparenleft}x{\isacharcomma}\ t{\isacharparenright}\ {\isasymin}\ M\isactrlsup {\isacharasterisk}{\isacharsemicolon}\ t\ {\isasymin}\ A{\isasymrbrakk}\ {\isasymLongrightarrow}\ x\ {\isasymin}\ lfp\ {\isacharparenleft}{\isasymlambda}T{\isachardot}\ A\ {\isasymunion}\ M{\isasyminverse}\ {\isacharbackquote}{\isacharbackquote}\ T{\isacharparenright}% -\end{isabelle} -This goal is proved by induction on \isa{{\isacharparenleft}s{\isacharcomma}\ t{\isacharparenright}\ {\isasymin}\ M\isactrlsup {\isacharasterisk}}. But since the model -checker works backwards (from \isa{t} to \isa{s}), we cannot use the -induction theorem \isa{rtrancl{\isacharunderscore}induct}: it works in the -forward direction. Fortunately the converse induction theorem -\isa{converse{\isacharunderscore}rtrancl{\isacharunderscore}induct} already exists: -\begin{isabelle}% -\ \ \ \ \ {\isasymlbrakk}{\isacharparenleft}a{\isacharcomma}\ b{\isacharparenright}\ {\isasymin}\ r\isactrlsup {\isacharasterisk}{\isacharsemicolon}\ P\ b{\isacharsemicolon}\isanewline -\isaindent{\ \ \ \ \ \ }{\isasymAnd}y\ z{\isachardot}\ {\isasymlbrakk}{\isacharparenleft}y{\isacharcomma}\ z{\isacharparenright}\ {\isasymin}\ r{\isacharsemicolon}\ {\isacharparenleft}z{\isacharcomma}\ b{\isacharparenright}\ {\isasymin}\ r\isactrlsup {\isacharasterisk}{\isacharsemicolon}\ P\ z{\isasymrbrakk}\ {\isasymLongrightarrow}\ P\ y{\isasymrbrakk}\isanewline -\isaindent{\ \ \ \ \ }{\isasymLongrightarrow}\ P\ a% -\end{isabelle} -It says that if \isa{{\isacharparenleft}a{\isacharcomma}\ b{\isacharparenright}\ {\isasymin}\ r\isactrlsup {\isacharasterisk}} and we know \isa{P\ b} then we can infer -\isa{P\ a} provided each step backwards from a predecessor \isa{z} of -\isa{b} preserves \isa{P}.% -\end{isamarkuptxt}% +\isamarkuptrue% +\isamarkupfalse% +\isamarkupfalse% +\isamarkuptrue% +\isamarkupfalse% \isamarkuptrue% -\isacommand{apply}{\isacharparenleft}erule\ converse{\isacharunderscore}rtrancl{\isacharunderscore}induct{\isacharparenright}\isamarkupfalse% -% -\begin{isamarkuptxt}% -\noindent -The base case -\begin{isabelle}% -\ {\isadigit{1}}{\isachardot}\ {\isasymAnd}x\ t{\isachardot}\ t\ {\isasymin}\ A\ {\isasymLongrightarrow}\ t\ {\isasymin}\ lfp\ {\isacharparenleft}{\isasymlambda}T{\isachardot}\ A\ {\isasymunion}\ M{\isasyminverse}\ {\isacharbackquote}{\isacharbackquote}\ T{\isacharparenright}% -\end{isabelle} -is solved by unrolling \isa{lfp} once% -\end{isamarkuptxt}% -\ \isamarkuptrue% -\isacommand{apply}{\isacharparenleft}subst\ lfp{\isacharunderscore}unfold{\isacharbrackleft}OF\ mono{\isacharunderscore}ef{\isacharbrackright}{\isacharparenright}\isamarkupfalse% -% -\begin{isamarkuptxt}% -\begin{isabelle}% -\ {\isadigit{1}}{\isachardot}\ {\isasymAnd}x\ t{\isachardot}\ t\ {\isasymin}\ A\ {\isasymLongrightarrow}\ t\ {\isasymin}\ A\ {\isasymunion}\ M{\isasyminverse}\ {\isacharbackquote}{\isacharbackquote}\ lfp\ {\isacharparenleft}{\isasymlambda}T{\isachardot}\ A\ {\isasymunion}\ M{\isasyminverse}\ {\isacharbackquote}{\isacharbackquote}\ T{\isacharparenright}% -\end{isabelle} -and disposing of the resulting trivial subgoal automatically:% -\end{isamarkuptxt}% -\ \isamarkuptrue% -\isacommand{apply}{\isacharparenleft}blast{\isacharparenright}\isamarkupfalse% -% -\begin{isamarkuptxt}% -\noindent -The proof of the induction step is identical to the one for the base case:% -\end{isamarkuptxt}% +\isamarkupfalse% +\isamarkuptrue% +\isamarkupfalse% \isamarkuptrue% -\isacommand{apply}{\isacharparenleft}subst\ lfp{\isacharunderscore}unfold{\isacharbrackleft}OF\ mono{\isacharunderscore}ef{\isacharbrackright}{\isacharparenright}\isanewline +\isamarkupfalse% \isamarkupfalse% -\isacommand{apply}{\isacharparenleft}blast{\isacharparenright}\isanewline \isamarkupfalse% -\isacommand{done}\isamarkupfalse% % \begin{isamarkuptext}% The main theorem is proved in the familiar manner: induction followed by @@ -215,11 +131,9 @@ \isamarkuptrue% \isacommand{theorem}\ {\isachardoublequote}mc\ f\ {\isacharequal}\ {\isacharbraceleft}s{\isachardot}\ s\ {\isasymTurnstile}\ f{\isacharbraceright}{\isachardoublequote}\isanewline \isamarkupfalse% -\isacommand{apply}{\isacharparenleft}induct{\isacharunderscore}tac\ f{\isacharparenright}\isanewline +\isamarkupfalse% \isamarkupfalse% -\isacommand{apply}{\isacharparenleft}auto\ simp\ add{\isacharcolon}\ EF{\isacharunderscore}lemma{\isacharparenright}\isanewline \isamarkupfalse% -\isacommand{done}\isamarkupfalse% % \begin{isamarkuptext}% \begin{exercise}