Hi, I'd like to use regular expressions in my code, so I looked at the ghc documentation on this library and it doesn't say much. RegexString looks great but I don't know how to use it. Some examples would be greatly appreciated! Regex itself has even less documentation. From RegexString: "mkRegex makes a regular expression with the default options (multi-line, case-sensitive), whereas mkRegexWithOpts takes the values for these options as parameteres. The syntax of regular expressions is otherwise that of Perl." Then what's wrong with let exp = mkRegex "^class\(\[(.*)\]," in This would be the Perl syntax for the regexp. It says ghc -package text -c -o RegT.o RegT.hs RegT.hs:13: error in character literal I checked and it doesn't like the escaped ( [ and ]. So how do I escape them? The unescaped inner round brackets mean that I want to collect the result of this match, whereas the escaped brackets mean that these are actual characters I want to match. My text to match looks like this: class([1,0,0,0],"METABOLISM"). class([1,1,0,0],"amino-acid metabolism"). class([1,1,1,0],"amino-acid biosynthesis"). Amanda -- Amanda Clare http://users.aber.ac.uk/ajc99/ Tel: +44 (0)1970 621922 Fax: +44 (0)1970 622455 Dept. of Computer Science, University of Wales, Aberystwyth, SY23 3DB