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+\documentclass{article}
+\usepackage{../style}
+\usepackage{../langs}
+\usepackage{marvosym}
+
+%cheat sheet
+%http://worldline.github.io/scala-cheatsheet/
+
+\begin{document}
+
+\section*{Scala in 6CCS3CFL}
+
+For the coursework in this module you are free to use any programming
+language you like, but I will show you all my code using Scala---I hope
+you have fond memories of Scala from PEP. I will use the current
+stable version of Scala, which is 2.13.3. If you need a reminder of
+the Scala handouts for PEP have a look
+\hr{http://talisker.nms.kcl.ac.uk/cgi-bin/repos.cgi/pep-material/raw-file/tip/handouts/pep-ho.pdf}\bigskip
+
+\noindent
+The main difference to the Scala I showed you in PEP is that in CFL
+I will use the Ammonite REPL
+
+\begin{quote}
+\url{https://ammonite.io/#Ammonite-REPL}
+\end{quote}
+
+\noindent
+This is a drop-in replacement for the original Scala REPL and
+works very similarly, for example
+
+\begin{lstlisting}[language={},numbers=none,basicstyle=\ttfamily\small]
+$ amm
+Loading...  
+Welcome to the Ammonite Repl 2.2.0 (Scala 2.13.3 Java 9)
+scala> 1 + 2 
+res0: Int = 3
+\end{lstlisting} %% $
+
+\noindent
+Ammonite uses the same Scala compiler, just adds some useful features
+on top of it. It is quite main-stream in the Scala community and it should
+therefore be very easy for you to install \texttt{amm}.  The big
+advantage of Ammonite is that it comes with some additional libraries
+already built-in and also allows one to easily break up code into
+smaller modules. For example reading and writing files in Ammonite can
+be achieved with
+
+\begin{lstlisting}[numbers=none,language=Scala]
+scala> import ammonite.ops._
+  
+scala> read(pwd / "file.name")   
+res1: String = """..."""
+
+scala> write.over(pwd / "file.name", "foo bar")
+\end{lstlisting}
+
+\noindent
+For loading and accessing code from another Scala file, you can import it
+as follows:
+
+\begin{lstlisting}[numbers=none,language=Scala]
+import $file.name-of-the-file
+import name-of-the-file._
+\end{lstlisting}  %% $
+
+\noindent
+This assumes the other Scala file is called
+\texttt{name-of-the-file.sc} and requires the file to be in the same
+directory where \texttt{amm} is working in. This will be very convenient 
+for the compiler we implement in CFL, because it allows us to easily
+break-up the code into the lexer, parser and code generator.
+
+Another feature which exists in Ammonite, but not yet in the
+current version of Scala (it will be in the next version called dotty)
+is that you can mark functions as \texttt{@main}. For example
+
+\begin{lstlisting}[numbers=none,language=Scala]
+@main
+def foo() = ...
+\end{lstlisting}
+
+\noindent
+This means you can now call that function from the command line like
+
+\begin{lstlisting}[numbers=none,language=Scala]
+$ amm file.sc foo
+\end{lstlisting} %% $
+
+\noindent
+If you want to specify an argument on the commandline, say an int and
+a string, then you can write
+
+\begin{lstlisting}[numbers=none,language=Scala]
+@main
+def bar(i: Int, s: String) = ...
+\end{lstlisting}
+
+\noindent
+and then call
+
+\begin{lstlisting}[numbers=none,language=Scala]
+$ amm file.sc 42 foobar
+\end{lstlisting} %% $
+
+\noindent
+What is also good in Ammonite that you can specify more than one
+function to be ``main'' and then specify on the command line which
+function do you want to run as entry-point.\bigskip
+
+\noindent
+To sum up, Ammonite is a really useful addition to the Scala ecosystem.
+You can find more information about how to use it in the first five chapters
+of the ``Hands-on Scala'' book by Li Haoyi. These chapters are
+free and can be used as a reference, see:
+
+\begin{center}
+\url{https://www.handsonscala.com/part-i-introduction-to-scala.html}
+\end{center}
+
+\end{document}
+
+%%% Local Variables: 
+%%% mode: latex
+%%% TeX-master: t
+%%% End: