Multi-line regular expressions are indeed powerful. Rob Pike has a good paper on it available at:
http://doc.cat-v.org/bell_labs/structural_regexps/se.pdf<http://code.google.com/p/sregex/> <http://code.google.com/p/sregex/>Explains how line-based regular expressions are limiting etc. The Sam and Acme editors supported these. Python does too now. http://code.google.com/p/sregex/ On Wed, Nov 4, 2009 at 6:17 AM, kenny lu <haskellm...@gmail.com> wrote: > Michael, > > Here is how I do it. > > > > module Main where > > > import Text.Regex.Posix.ByteString > > import Data.Maybe > > import qualified Data.ByteString.Char8 as S > > > text = S.pack "11\n abcd \n22" > > p = S.pack "11\n(.*)\n22" > > > > main :: IO () > > main = > > do { (Right pat) <- compile compExtended execBlank p > > ; res <- regexec pat text > > ; case res of > > { (Right (Just (_,_,_,m))) -> putStrLn (show m) > > ; _ -> putStrLn "not matched." > > } > > } > > You may swap out ByteString with String, > PCRE should be similar, too. > > Regards, > Kenny > > > > On Wed, Nov 4, 2009 at 2:04 PM, Michael Mossey <m...@alumni.caltech.edu>wrote: > >> >> >> kenny lu wrote: >> >>> Hi Michael, >>> >>> Could you give an example of what patterns you want to write? >>> >>> Regards, >>> Kenny >>> >>> >> Something like >> >> text = "11\n abcd \n22" >> answer = text =~ "11.*22" :: <various possibilities> >> >> and have it find the entire string. The default behavior is to stop >> matching when it encounters a newline. There is mention in the >> Text.Regex.Posix docs of a flag to control this behavior, but it is not easy >> to figure out from the docs how to provide flags. The left-hand side of the >> =~ is a very complex type. >> >> >> >> >> >> _______________________________________________ >> Haskell-Cafe mailing list >> Haskell-Cafe@haskell.org >> http://www.haskell.org/mailman/listinfo/haskell-cafe >> > > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe > >
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