% simianer-regexvis.tex % Patrick Simianer % YYYY-MM-DD \documentclass[ignorenonframetext]{beamer} \mode { \usetheme{Singapore} \usecolortheme{dolphin} \usefonttheme{professionalfonts} \useinnertheme{circles} \useoutertheme{miniframes} \setbeamertemplate{navigation symbols}{} \beamersetuncovermixins{\opaqueness<1>{5}}{\opaqueness<2->{15}} \setbeamertemplate{footline}[frame number] } \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc} \usepackage[ngerman]{babel} \usepackage{lmodern} \usepackage{framed} \usepackage{color} \usepackage{multirow} \usepackage{listings} \lstset{basicstyle=\scriptsize\ttfamily, commentstyle=\color{gray}, emphstyle=\sffamily\bfseries} \lstset{keywordstyle=\sffamily\bfseries, commentstyle=\color{gray}, stringstyle=\color{black}} \lstset{numbers=none, numberstyle=\tiny} \usepackage{tikz} \usetikzlibrary{arrows,automata} \title[regexvis]{Patrick Simianer\\ Visualisierung regulärer Ausdrücke} \author{Patrick~Simianer \tiny 2508483\\\normalsize 2010-06-28} \date{Endliche Automaten HS bei Dr. Karin Haenelt\\ Universitiät Heidelberg im Sommersemester 2010} \AtBeginSection[]{% \begin{frame} \tableofcontents[currentsection] \end{frame} }% AtBeginSection \begin{document} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \frame[plain]{\titlepage} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \begin{frame}[plain] \frametitle{Gliederung} \tableofcontents \end{frame} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \section{Einleitung} \subsection{"Uberlegungen} \begin{frame} \frametitle{Visualisierung regul"arer Ausdr"ucke /1} \begin{itemize} \item[] Wie soll die Visualisierung aussehen? \begin{enumerate} \item Hervorheben von \textit{\textbf{Matches}} oder \textbf{Gruppen} in einem String oder Text \item Darstellung und Simulation durch einen \textbf{Automaten} \end{enumerate} \item[] \end{itemize} \begin{enumerate} \item Zu Hauf zu vorhanden, \\ basierend auf RE-Implementierung der jeweiligen Sprache\\ $\rightarrow$ keine ``\textit{step by step}''-Visualisierung m"oglich \item Grafische Umsetzung schwierig,\\ eigene RE-Implementierung n"otig\\ $\rightarrow$ jeder Schritt nachvollziehbar \end{enumerate} \end{frame} \begin{frame} \frametitle{Visualisierung regul"arer Ausdr"ucke /2} \begin{enumerate} \item Wie k"onnen regul"are Ausdr"ucke m"oglichst einfach und effizient implementiert werden? \begin{itemize} \item ``Herk"ommliche'' \textbf{Backtracking}-Methode (\textit{Perl}, \textit{PCRE}) \item[$\Rightarrow$] Direkte Konstruktion eines \textbf{endlichen Automaten} \end{itemize} \item[] \item Soll der Automat dargestellt werden und wenn ja, wie? \begin{itemize} \item[$\Rightarrow$] \textbf{Ja}, im besten Fall mit Animationen... \end{itemize} \item[] \item In welcher Umgebung k"onnen alle Teile (1. Parser, 2. GUI, 3. Visualisierung) gut implementiert werden? \begin{itemize} \item[$\Rightarrow$] \textbf{Browser}-basiert (1. \textit{JavaScript}, 2. \textit{HTML}, 3. \textit{SVG}) \end{itemize} \end{enumerate} \end{frame} \subsection{Protoypisches Vorgehen} \begin{frame} \frametitle{Protoypisches Vorgehen} \begin{enumerate} \item \textbf{Parsen} des Ausdrucks \item Umsetzung in einen \textbf{nichtdeterministischen endlichen Automaten} \item Übersetzung des NDEA in einen \textbf{deterministischen} endlichen Automaten \item Grafische \textbf{Darstellung} des Automaten und dessen \textbf{Simulation} \item[] \item[] Umsetzung im \textbf{Browser}: \textit{JavaScript} (\textit{Rapha\"el} f"ur \textit{SVG}, \textit{jQuery}), \textit{HTML}+\textit{CSS} \end{enumerate} \end{frame} \subsection{Konkreter Aufbau} \begin{frame}[plain] %\frametitle{Konkreter Aufbau} \begin{center} \begin{figure} \includegraphics[scale=0.65]{a1.pdf} \caption{Konkreter System-Aufbau} \end{figure} \end{center} \end{frame} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \section{Einfaches Parsing regul"arer Ausdr"ucke} \subsection{Recursive Descent-Methode} \begin{frame}[fragile] \frametitle{\textit{Recursive Descent}-Methode} \begin{columns} \column{4cm} \textbf{Grammatik:} \hrule \column{7.5cm} \textbf{Code:} \hrule \end{columns} \begin{columns} \column{4cm} {\scriptsize\begin{tabular}{ll} \textbf{expr} & $\rightarrow$ term | term \underline{|} expr \\ term & $\rightarrow$ factor | term \\ factor & $\rightarrow$ atom kleene \\ atom & $\rightarrow$ literal | \underline{(} expr \underline{)}\\ kleene & $\rightarrow$ \underline{$*$} kleene | $\epsilon$\\ literal & $\rightarrow$ \underline{a} | \underline{b} | \underline{c} | \underline{\%} \end{tabular}} \column{7.5cm} \lstset{language=C++, emph={RegexParser}} \begin{lstlisting} RegexParser.prototype.expr = function() { var nfa = this.term(); if (this.trymatch('|')) { return nfa.union(this.expr()); }; return nfa; }; \end{lstlisting} \end{columns} \begin{itemize} \item Nahezu direktes "Ubersetzen einer Grammatik\footnote{keine Links-Rekursionen, sonst: Endlosschleife} in den Quelltext des Parsers (LL(1)) \item $\forall$ Nichtterminale $\exists$ Funktion, welche die rechte Seite der jeweiligen Regel behandelt \item Direkte Erzeugung des NDEA, mittels Konstruktion nach Thompson %\item Schnell, einfach und effizient \end{itemize} \end{frame} \subsection{Thompson's Algorithmus} \begin{frame} \frametitle{Thompson's Algorithmus} \begin{itemize} \item[{\color{red}Konkatenation: \texttt{ab}}] \begin{center}\includegraphics[scale=0.22]{ab.pdf}\end{center} \item[] \item[{\color{green}H"ulle: \texttt{a*}}] \begin{center}\includegraphics[scale=0.22]{astar.pdf}\end{center} \item[] \item[{\color{blue}Vereinigung: \texttt{(a|b)}}] \begin{center}\includegraphics[scale=0.22]{aorb.pdf}\end{center} \end{itemize} \end{frame} \subsection{Beispiel} \begin{frame} \frametitle{Thompson's Algorithmus: Beispiel} Regulärer Ausdruck: \texttt{a(a|b)c*} \vspace{0.5cm} \begin{centering} \includegraphics[scale=0.23]{aabc.pdf} \end{centering} \end{frame} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \section{"Uberf"uhrung NDEA zu einem DEA} \subsection*{Einleitung} \begin{frame} \frametitle{Einleitung} \begin{itemize} \item[] Warum den erzeugten NDEA in einen DEA "uberf"uhren? \item[] \item \textit{trade-off}: \begin{tabular}{rll} Platzbedarf & $-$NDEA & \textbf{$\mathbf{+}$DEA}\\ Erstellungszeit & \textbf{$\mathbf{+}$NDEA} & $-$DEA\\ Ausf"uhrungszeit & $-$NDEA & \textbf{$\mathbf{+}$DEA}\\ \end{tabular} \item[] \item NDEAs\footnote{insbesondere die hier erzeugten} umfassen f"ur gew"ohnlich sehr viele Zust"ande, die Darstellung eines DEA ist praktikabler \end{itemize} \end{frame} \subsection{$\epsilon$-Abschluss} \begin{frame}[fragile] \frametitle{$\epsilon$-Abschluss} \textbf{Pseudo-Code} \hrule \begin{columns} \column{5cm} \lstset{language=C++, emph={epsclosure,move}} \begin{lstlisting} epsclosure(NFAState) { } \end{lstlisting} \column{5cm} \lstset{language=C++, emph={move}} \begin{lstlisting} nfa2dfa(NFA) { } \end{lstlisting} \end{columns} \end{frame} \subsection{Beispiel} \begin{frame}[plain] \frametitle{NDEA $\rightarrow$ DEA Beispiel} Regul"arer Ausdruck: \texttt{(a|b)*} \begin{center} \includegraphics[scale=0.27]{aorbstar0.pdf} \end{center} \end{frame} \begin{frame}[plain] \begin{center} \begin{tabular}{c|c|c} Dfa ID & Symbol & $\rightarrow$Dfa ID\\ \hline \multirow{2}{*}{\{6, 7, 4, 0, 2\}} & $a$ & \{1, 5, 7, 4, 0, 2\} \\ & $b$ & \{3, 5, 7, 4, 0, 2\} \\ \hline \multirow{2}{*}{\{1, 5, 7, 4, 0, 2\}} & $a$ & \{1, 5, 7, 4, 0, 2\}\\ & $b$ & \{3, 5, 7, 4, 0, 2\}\\ \hline \multirow{2}{*}{\{3, 5, 7, 4, 0, 2\}}& $a$ & \{1, 5, 7, 4, 0, 2\}\\ & $b$ & \{3, 5, 7, 4, 0, 2\}\\ \end{tabular} \end{center} \begin{center} \includegraphics[scale=.175]{aorbstar.pdf} \end{center} \end{frame} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \begin{frame}[allowframebreaks] \frametitle{Literatur} \bibliographystyle{alpha} \bibliography{beamer} \nocite{*} \end{frame} \begin{frame} \frametitle{Resourcen} \begin{itemize} \item \textit{Rapha\"el} JavaScript SVG Library (\url{http://raphaeljs.com/}) \item \textit{jQuery} JavaScript Library (\url{http://jquery.com/}) \item Scalable Vector Graphics (\textit{SVG}) 1.1 Specification (\url{http://www.w3.org/TR/SVG/}) \item Writing your own regular expression parser (\url{http://www.codeproject.com/KB/recipes/OwnRegExpressionsParser.aspx}) \end{itemize} \end{frame} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \section{Demo} \begin{frame}[plain] \begin{center} \Huge{Demo} \end{center} \end{frame} \section{Weiterentwicklung} \begin{frame} \frametitle{Weiterentwicklung} \begin{itemize} \item Vorhanden: * | () \end{itemize} \end{frame} \end{document}