http://ayende.comAyende @ RahienCopyright (C) Ayende Rahien 2004 - 2021 (c) 202660Ooops, didn't see James' comment above... and it looks like it works. The Regex.Escape() method does pretty much what I described above. From the docs: "Escapes a minimal set of characters (\, *, +, ?, |, {, [, (,), ^, $,., #, and white space) by replacing them with their escape codes." That's handy. http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment19http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment19Thu, 21 May 2009 22:45:35 GMTDon't know if you're still having issues here, but it looks like you need to escape the '*' and '.' characters in the pattern. Also, you probably need to compact the whitespace in the pattern to as few as possible, then replace them with \s* http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment18http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment18Thu, 21 May 2009 22:40:29 GMTCory, Yes, I know about that, but since this is a WPF app, and Mono doesn't have that, I don't worry too much about it http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment17http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment17Tue, 12 May 2009 05:45:50 GMTFYI - I know the multiline syntax is handy from a readability perspective, but tests like that may not pass on Mono/Linux or any other OS that doesn't use \r\n as the line terminator: [www.cornetdesign.com/.../...nvironmentnewline.html](http://www.cornetdesign.com/2006/03/importance-of-systemenvironmentnewline.html) To get it to pass, you'd have to recompile on the platform. Well, unless you *are* developing this on Mono/Linux, but I don't think that's the case. :) http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment16http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment16Tue, 12 May 2009 03:56:31 GMTWhy would we care about the regex when the entire principle this is based on is a big hairy WTF? http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment15http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment15Mon, 11 May 2009 21:22:36 GMTCool. That part does look convoluted :) http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment14http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment14Mon, 11 May 2009 20:22:22 GMTBertrand, Well, when you only see a very small part, it is not surprising http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment13http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment13Mon, 11 May 2009 20:17:33 GMT@Chris I was only providing one example of what would be escaped. As Sergey and bobo mentioned, the comment tags also cause an issue because '*' is a regex quantifier, and as such, is escaped by Regex.Escape as well. http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment12http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment12Mon, 11 May 2009 19:19:02 GMT const string EXPECTED = @"Cached query: SELECT this_.Id as Id5_0_, this_.Title as Title5_0_, this_.Subtitle as Subtitle5_0_, this_.AllowsComments as AllowsCo4_5_0_, this_.CreatedAt as CreatedAt5_0_ FROM Blogs this_ WHERE this_.Title = 'The lazy blog' /* @p0 */ and this_.Id = 1 /* @p1 */"; string pattern = Regex.Escape(EXPECTED).Replace("5_", @"\d+_"); Assert.True(Regex.IsMatch(EXPECTED, pattern)); http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment11http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment11Mon, 11 May 2009 19:11:10 GMTThere isn't anything wrong with the string, but that regex will never work, as it's going to change all the digits to 5. Should be this: @"\d+_(?=0)" That does a lookahead and only matches digits followed by an _ then a 0. The 0 is then not part of the grouping and so won't be changed. It doesn't make sense, why would you want to do that anyway? http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment10http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment10Mon, 11 May 2009 19:07:53 GMTRegex.IsMatch(expected,Regex.Escape(expected).Replace("5_", @"\d+_")) passes http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment9http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment9Mon, 11 May 2009 19:05:30 GMTAren't tests supposed to be readable? I have no idea what this is supposed to do from staring at the code. Might be just me though. http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment8http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment8Mon, 11 May 2009 19:04:16 GMTSo, is Replace doing something funny to the asterisk or what?... http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment7http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment7Mon, 11 May 2009 18:40:12 GMTIt's a problem with the comment tags in the SQL statement. Remove the comments and the regular expression passes. http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment6http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment6Mon, 11 May 2009 18:17:29 GMTMaybe Regex.Escape before you do your Replace might help... http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment5http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment5Mon, 11 May 2009 18:08:57 GMTit's the /* */ comments... http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment4http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment4Mon, 11 May 2009 18:03:44 GMTBut regex "/* " won't match string "/* ". http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment3http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment3Mon, 11 May 2009 18:03:42 GMTMichael: '.' will match any single character, so that will still work; it will just match more than expected. I might guess that the newlines are confusing the regex engine. http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment2http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment2Mon, 11 May 2009 17:49:50 GMTRegex.IsMatch(expected, Regex.Escape(expected).Replace(@"5_", @"\d+_")) The query contains regex characters which need to be escaped (i.e. '.'). It's a bit messy ... if this is going to be used a lot, would probably be good to replace the whitespace with '\s+', etc. http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment1http://ayende.com/4005/challenge-the-regex-that-doesn-t-match#comment1Mon, 11 May 2009 17:45:52 GMT