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\documentclass[dvipsnames,14pt,t,xelatex]{beamer}
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\usepackage{../slides}
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\usepackage{../graphics}
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\usepackage{../langs}
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%\usepackage{../data}
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\hfuzz=220pt
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%\setmonofont[Scale=.88]{Consolas}
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%\newfontfamily{\consolas}{Consolas}
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\lstset{language=Scala,
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style=mystyle,
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numbersep=0pt,
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numbers=none,
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xleftmargin=0mm}
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\newcommand{\bl}[1]{\textcolor{blue}{#1}}
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% beamer stuff
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\renewcommand{\slidecaption}{PEP (Scala) 02, King's College London}
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\begin{document}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{%
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\begin{tabular}{@ {}c@ {}}
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\\[5mm]
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\huge PEP Scala (2)
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\end{tabular}}
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\normalsize
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\begin{center}
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\begin{tabular}{ll}
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Email: & christian.urban at kcl.ac.uk\\
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Office: & N7.07 (North Wing, Bush House)\\
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Slides \& Code: & KEATS\medskip\\
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Scala Office & \\
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Hours: & Thursdays 11 -- 13\\
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\end{tabular}
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\end{center}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t,fragile]
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\frametitle{Mea Culpa}
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\bigskip
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\mbox{\hspace{-4mm}}CW6, Part 3 (deadline 21 December)\bigskip\medskip
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\small
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\begin{lstlisting}[language=Scala, numbers=none, xleftmargin=-4mm]
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val blchip_portfolio =
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List("GOOG", "AAPL", "MSFT", "IBM", "FB",
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"YHOO", "AMZN", "BIDU")
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val rstate_portfolio =
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List("PLD", "PSA", "AMT", "AIV", "AVB",
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"BXP", "CBG", "CCI",
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"DLR", "EQIX", "EQR", "ESS", "EXR",
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"FRT", "GGP", "HCP")
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\end{lstlisting}\bigskip
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\onslide<2>{The results in the CW are calculated with YHOO and CBG deleted.}
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\only<2>{
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\begin{textblock}{6}(8.5,6.6)
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\begin{tikzpicture}
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\node (B0) at (0,0) {};
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\node (B1) at (0,0.5) {};
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\node (B2) at (1.2,0) {};
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\node (B3) at (1.2,0.5) {};
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\draw [red,line width=1mm] (B0) -- (B3);
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\draw [red,line width=1mm] (B1) -- (B2);
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\end{tikzpicture}
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\end{textblock}}
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\only<2>{
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\begin{textblock}{6}(10.5,9.9)
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\begin{tikzpicture}
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\node (B0) at (0,0) {};
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\node (B1) at (0,0.5) {};
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\node (B2) at (1.2,0) {};
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\node (B3) at (1.2,0.5) {};
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\draw [red,line width=1mm] (B0) -- (B3);
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\draw [red,line width=1mm] (B1) -- (B2);
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\end{tikzpicture}
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\end{textblock}}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[c]
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\frametitle{Mea Culpa 2}
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Avoid at all costs, even in comments
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\begin{itemize}
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\item \texttt{var} \only<2>{$\quad\Rightarrow\;$\texttt{Var}}
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\item \texttt{return} \only<2>{$\quad\Rightarrow\;$\texttt{Return}}
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\item \texttt{.par}
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\item \texttt{ListBuffer}
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\item \texttt{mutable}
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\end{itemize}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{For-Comprehensions Again}
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\begin{center}
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\begin{tikzpicture}[scale=1,
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node/.style={
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rectangle,rounded corners=3mm,
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very thick,draw=black!50,
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minimum height=18mm, minimum width=20mm,
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top color=white,bottom color=black!20}]
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\node (A0) at (0.1,0) {\texttt{\textcolor{purple}{\textbf{for}} (\alert<2->{n} <- List(}};
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\node (A1) at (2.3,0) {\texttt{\phantom{,}1,}};
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\node (A2) at (3.2,0) {\texttt{\phantom{,}2,}};
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\node (A3) at (4.1,0) {\texttt{\phantom{,}3,}};
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\node (A4) at (5.0,0) {\texttt{\phantom{,}4,}};
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\node (A5) at (5.9,0) {\texttt{\phantom{))}5))}};
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\node (A6) at (8,0) {\texttt{\textcolor{purple}{\textbf{yield}} \alert<2->{n\,*\,n}}};
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\onslide<2->{
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\node (B0) at (1.4,-3) {\texttt{List(}};
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\node (B1) at (2.3,-3) {\texttt{\phantom{,}1,}};
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\node (B2) at (3.6,-3) {\texttt{\phantom{,}4,}};
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\node (B3) at (4.9,-3) {\texttt{\phantom{,}9,}};
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\node (B4) at (6.2,-3) {\texttt{\phantom{,}16,}};
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\node (B5) at (7.5,-3) {\texttt{\phantom{,}25)}};}
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\onslide<2->{
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\draw [->,line width=1mm] (A1.south) -- (B1.north);
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\draw [->,line width=1mm] (A2.south) -- (B2.north);
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\draw [->,line width=1mm] (A3.south) -- (B3.north);
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\draw [->,line width=1mm] (A4.south) -- (B4.north);
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\draw [->,line width=1mm] (A5.south) -- (B5.north);}
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\onslide<2->{
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\node (Q1) at (-0.45,-0.1) {};
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\node (Q2) at (-0.45,-2.8) {};
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\node (Q3) at (-0.45,-2.95) {\alert<2->{\texttt{n\,*\,n:}}};
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\draw [->,red,line width=1mm] (Q1.south) -- (Q2.north);}
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\end{tikzpicture}
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\end{center}
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\onslide<3>{This is for when the for-comprehension\\ \textbf{yields / produces} a result.}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{For-Comprehensions Again}
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\begin{center}
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\begin{tikzpicture}[scale=1,
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node/.style={
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rectangle,rounded corners=3mm,
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very thick,draw=black!50,
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minimum height=18mm, minimum width=20mm,
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top color=white,bottom color=black!20}]
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\node (A0) at (0,0)
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{\texttt{\textcolor{purple}{\textbf{for}} (n <- List(1, 2, 3, 4, 5))
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\textcolor{purple}{\textbf{yield}} n\,*\,n}};
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\node (A1) at (0,-1.5) {\LARGE\textbf{vs}};
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\node (A2) at (0,-3)
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{\texttt{\textcolor{purple}{\textbf{for}} (n <- List(1, 2, 3, 4, 5)) println(n)}};
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\end{tikzpicture}
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\end{center}\bigskip
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The second version is in case the for \textbf{does not}
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produce any result.
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{\begin{tabular}{c}Why Scala?\end{tabular}}
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\begin{itemize}
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\item \large {\bf You can avoid \textcolor{blue}{\texttt{null}}}:
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\end{itemize}
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\begin{textblock}{6}(1,5)
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\begin{bubble}[10.5cm]\small
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``I call it my billion-dollar mistake. It was the invention of
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the null reference in 1965. At that time, I was designing the
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first comprehensive type system for references in an object
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oriented language (ALGOL W). My goal was to ensure that all use
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of references should be absolutely safe, with checking performed
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automatically by the compiler. But I couldn't resist the
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temptation to put in a null reference, simply because it was so
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easy to implement. This has led to innumerable errors,
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vulnerabilities, and system crashes, which have probably caused
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a billion dollars of pain and damage in the last forty years.''
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\hfill Sir Tony (Hoare)
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\end{bubble}
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\end{textblock}
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\begin{textblock}{5}(11.8,1)
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%%\includegraphics[scale=0.20]{hoare.jpg}\\
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\end{textblock}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[c]
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\frametitle{Types}
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\begin{itemize}
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\item Base types\smallskip
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\begin{tabular}{@{}l@{}}
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\textcolor{codegreen}{\texttt{Int}},
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\textcolor{codegreen}{\texttt{Long}},
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\textcolor{codegreen}{\texttt{BigInt}},
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\textcolor{codegreen}{\texttt{Float}},
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\textcolor{codegreen}{\texttt{Double}}\\
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\textcolor{codegreen}{\texttt{String}},
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\textcolor{codegreen}{\texttt{Char}}\\
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\textcolor{codegreen}{\texttt{Boolean}}
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\end{tabular}
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\item Compound types \smallskip
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\begin{tabular}{@{}ll@{}}
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\textcolor{codegreen}{\texttt{List[Int]}} & lists of Int's \\
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\textcolor{codegreen}{\texttt{Set[Double]}} & sets of Double's \\
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\textcolor{codegreen}{\texttt{(Int, String)}} & Int-String pair\\
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\textcolor{codegreen}{\texttt{List[(BigInt, String)]}} &
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lists of BigInt-String\\
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& pairs\\
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\textcolor{codegreen}{\texttt{List[List[Int]]}} & list of lists of Int's\\
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\end{tabular}
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\end{itemize}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[c]
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\frametitle{\begin{tabular}{c}\\[3cm]\alert{Questions?}\end{tabular}}
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\mbox{}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\end{document}
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\end{document}
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%%% Local Variables:
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%%% mode: latex
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%%% TeX-master: t
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%%% End:
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