handouts/ho01.tex
changeset 250 b79e704acb72
parent 248 ce767ca23244
child 252 e8ef8f38ca84
--- a/handouts/ho01.tex	Mon Sep 15 04:54:01 2014 +0100
+++ b/handouts/ho01.tex	Mon Sep 15 07:25:17 2014 +0100
@@ -101,14 +101,19 @@
 brackets\\
 \pcode{[^...]} & matches any single character not inside the 
 brackets\\
-\pcode{..-..} & character ranges\\
-\pcode{\\d} &	matches digits; equivalent to \pcode{[0-9]}
+\pcode{...-...} & character ranges\\
+\pcode{\\d} & matches digits; equivalent to \pcode{[0-9]}\\
+\pcode{.} & matches every character except newline\\
+\pcode{(re)}	& groups regular expressions and remembers 
+matched text
 \end{tabular}
 \end{center}
 
 \noindent With this table you can figure out the purpose of
 the regular expressions in the web-crawlers shown Figures
-\ref{crawler1}, \ref{crawler2} and \ref{crawler3}. Note,
+\ref{crawler1}, \ref{crawler2} and
+\ref{crawler3}.\footnote{There is an interesting twist in the
+web-scraber where \pcode{re*?} is used instead of \pcode{re*}.} Note,
 however, the regular expression for http-addresses in
 web-pages is meant to be