--- a/handouts/ho01.tex Fri Oct 10 16:59:22 2014 +0100
+++ b/handouts/ho01.tex Sat Oct 11 01:13:13 2014 +0100
@@ -17,14 +17,14 @@
\emph{not} just look for a particular string, but for string
patterns. For example in programming code we need to identify
what are the keywords, what are the identifiers etc. A pattern
-for identifiers could be that they start with a letter,
+for identifiers could be stated as: they start with a letter,
followed by zero or more letters, numbers and the underscore.
Also often we face the problem that we are given a string (for
example some user input) and want to know whether it matches a
particular pattern. In this way we can exclude user input that
would otherwise have nasty effects on our program (crashing it
or going into an infinite loop, if not worse). \defn{Regular
-expressions} help with conveniently specifying such patterns.
+expressions} help with conveniently specifying such patterns.
The idea behind regular expressions is that they are a simple
method for describing languages (or sets of strings)\ldots at
least languages we are interested in in computer science. For