{-# LANGUAGE QuasiQuotes #-}
module Main
where
import Text.Regex.Posix
import Text.RawString.QQ
haystack :: String
haystack = "My e-mail address is user@example.com"
needle :: String
needle = [r|\w+@[a-zA-Z_]+?\.[a-zA-Z]{2,3}|]
multiline :: String
multiline = [r|<HTML>
<HEAD>
<TITLE>Auto-generated html formated source</TITLE>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=windows-1252">
</HEAD>
<BODY LINK="#0000ff" VLINK="#800080" BGCOLOR="#ffffff">
<P> </P>
<PRE>|]
main :: IO ()
main = do
print multiline
print ""
print $ ((haystack =~ needle) :: String)