
diff -r 47bcc2178f4e -r 2c512713f08a handouts/scala-ho.tex
--- a/handouts/scala-ho.tex	Wed Aug 27 16:40:23 2014 +0100
+++ b/handouts/scala-ho.tex	Thu Aug 28 01:04:11 2014 +0100
@@ -19,17 +19,18 @@
 
 Scala is a programming language that combines functional and
 object-oriented programming-styles, and has received in the
-last five years quite a bit of attention. One reason for this
-attention is that, like the Java programming language, Scala
-compiles to the Java Virtual Machine (JVM) and therefore can
-run under MacOSX, Linux and Windows.\footnote{There are also
-experimental backends for Android and JavaScript.} Unlike
-Java, however, Scala often allows programmers to write very
-concise and elegant code. Some therefore say Scala is the much
-better Java. The Guardian, Twitter, Coursera, LinkedIn to name
-a few either rely entirely in their infrastructures on Scala,
-or some parts of there infrastructure uses it. If you want to
-try it out yourself, the Scala compiler can be downloaded from
+last five years or so quite a bit of attention. One reason for
+this attention is that, like the Java programming language,
+Scala compiles to the Java Virtual Machine (JVM) and therefore
+Scala programs can run under MacOSX, Linux and
+Windows.\footnote{There are also experimental backends for
+Android and JavaScript.} Unlike Java, however, Scala often
+allows programmers to write very concise and elegant code.
+Some therefore say Scala is the much better Java. Some
+companies (The Guardian, Twitter, Coursera, LinkedIn to name a
+few) either use Scala excusively in production code, or some
+part of it are written in Scala. If you want to try out Scala
+yourself, the Scala compiler can be downloaded from
 
 \begin{quote}
 \url{http://www.scala-lang.org}
@@ -54,8 +55,8 @@
 Read-Eval-Print-Loop) with which you can run and test small
 code-snippets without the need of the compiler. This helps a
 lot with interactively developing programs. Once you installed
-Scala correctly, you can start the interpreter by typing
-
+Scala correctly, you can start the interpreter by typing on
+the command line:
 
 \begin{quote}
 \begin{alltt}
@@ -828,12 +829,11 @@
   def ~ (r: Rexp) = SEQ(s, r)
   def ~ (r: String) = SEQ(s, r)
   def % = STAR(s)
-
 }
 \end{lstlisting}
 \end{quote}
  
-\noindent This might seem a bit complicated, but its effect is
+\noindent This might seem a bit overly complicated, but its effect is
 that I can now write regular expressions such as $ab + ac$ 
 even simpler as
 
@@ -898,17 +898,23 @@
 
 \subsection*{More Info}
 
-There is much more to Scala, then I can possibly describe
-here. There are a number of free books about Scala and of 
-course lots of help online.
+There is much more to Scala than I can possibly describe in
+this document. Fortunately there are a number of free books
+about Scala and of course lots of help online. For example
+
+\begin{itemize}
+\item \url{http://www.scala-lang.org/docu/files/ScalaByExample.pdf}
+\item \url{http://www.scala-lang.org/docu/files/ScalaTutorial.pdf}
+\end{itemize}
 
-While I am quite enthusiastic about Scala, I am happy to admit
-that it has more than a fair share of faults. The problem of
-having to give an explicit type to {\tt toSet}, but not {\tt
-toList} is one of them. There are also many ``deep'' things
-about types in Scala, which even to me seasoned functional
-programmer are puzzling. While implicits are great, they
-can also be a source of great head-aches, for example
+While I am quite enthusiastic about Scala, I am also happy to
+admit that it has more than its fair share of faults. The
+problem seen earlier of having to give an explicit type to
+{\tt toSet}, but not {\tt toList} is one of them. There are
+also many ``deep'' ideas about types in Scala, which even to
+me as seasoned functional programmer are puzzling. Whilst
+implicits are great, they can also be a source of great
+headaches, for example consider the code:
 
 \begin{quote}
 \begin{alltt}
@@ -917,22 +923,25 @@
 \end{alltt}
 \end{quote}
 
-\noindent This should raise a typing-error, but it does not.
+\noindent Rather than returning {\tt false}, this code should
+throw a typing-error. There are also many limitations Scala
+inherited from the JVM that can be really annoying. For
+example a fixed stack size. 
 
-While Scala has been a success in several high-profile
-companies, there is also a company, Yammer, which first used
-Scala in their production code but then moved away from it.
-According to Wikipedia, they did not like steep learning curve
-of Scala and also that new versions of Scala often introduced
-incompatibilities.
+Even if Scala has been a success in several high-profile
+companies, there is also a company (Yammer) that first used
+Scala in their production code, but then moved away from it.
+Allegedly they did not like the steep learning curve of Scala
+and also that new versions of Scala often introduced
+incompatibilities in old code.
 
-So all in all, Scala might not be a great teaching
-language, but I hope this is mitigated by the fact that I
-never require from you to write any Scala code. You only
-need to be able to read it. In the coursework you can use
-any programming language you like. If you want to use
-Scala for this, be my guest; if you do not, stick with the
-language you are most familiar with.
+So all in all, Scala might not be a great teaching language,
+but I hope this is mitigated by the fact that I never require
+you to write any Scala code. You only need to be able to read
+it. In the coursework you can use any programming language you
+like. If you want to use Scala for this, then be my guest; if
+you do not want, stick with the language you are most familiar
+with.
 
 \end{document}
 




