msc-projects-14.html
changeset 334 3238418b70ca
parent 333 846966afdad1
child 335 7338cef94b2b
--- a/msc-projects-14.html	Sun Nov 09 21:37:59 2014 +0000
+++ b/msc-projects-14.html	Sun Nov 09 21:47:40 2014 +0000
@@ -49,14 +49,14 @@
   <p>
   <B>Description:</b>  
   <A HREF="http://en.wikipedia.org/wiki/Regular_expression">Regular expressions</A> 
-  are extremely useful for many text-processing tasks such as finding patterns in texts,
+  are extremely useful for many text-processing tasks, such as finding patterns in texts,
   lexing programs, syntax highlighting and so on. Given that regular expressions were
   introduced in 1950 by <A HREF="http://en.wikipedia.org/wiki/Stephen_Cole_Kleene">Stephen Kleene</A>,
   you might think regular expressions have since been studied and implemented to death. But you would definitely be
   mistaken: in fact they are still an active research area. For example
   <A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/regex-parsing-derivatives.pdf">this paper</A> 
   about regular expression matching and derivatives was presented just last summer at the international 
-  FLOPS'14 conference. The task in this project is to implement their results.</p>
+  FLOPS'14 conference. The task in this project is to implement their results and use them for lexing.</p>
 
   <p>The background for this project is that some regular expressions are 
   &ldquo;<A HREF="http://en.wikipedia.org/wiki/ReDoS#Examples">evil</A>&rdquo;
@@ -106,9 +106,10 @@
   (for example subexpression matching, which my rainy-afternoon matcher cannot). I am sure they thought
   about the problem much longer than a single afternoon. The task 
   in this project is to find out how good they actually are by implementing the results from their paper. 
-  Their approach is based on the concept of derivatives.
-  I used them once myself in a <A HREF="http://www.inf.kcl.ac.uk/staff/urbanc/Publications/rexp.pdf">paper</A> 
-  in order to prove the <A HREF="http://en.wikipedia.org/wiki/Myhill–Nerode_theorem">Myhill-Nerode theorem</A>.
+  Their approach to regular expression matching is also based on the concept of derivatives.
+  I used derivatives very successfully once for something completely different in a
+  <A HREF="http://www.inf.kcl.ac.uk/staff/urbanc/Publications/rexp.pdf">paper</A> 
+  about the <A HREF="http://en.wikipedia.org/wiki/Myhill–Nerode_theorem">Myhill-Nerode theorem</A>.
   So I know they are worth their money. Still, it would be interesting to actually compare their results
   with my simple rainy-afternoon matcher and potentially &ldquo;blow away&rdquo; the regular expression matchers 
   in Python and Ruby (and possibly in Scala too). The application would be to implement a fast lexer for
@@ -623,7 +624,7 @@
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