Not sure I'm even in the right neighborhood with this. Need to screen for integer data. Am I going about this correctly? Michael ====== [michael@localhost ~]$ ghci GHCi, version 6.10.4: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer ... linking ... done. Loading package base ... linking ... done. Prelude> :m + Text.Regex.Base.RegexLike Prelude Text.Regex.Base.RegexLike> let r = makeRegex "[+-]?[0-9]+" <interactive>:1:8: No instance for (RegexMaker regex compOpt execOpt [Char]) arising from a use of `makeRegex' at <interactive>:1:8-30 Possible fix: add an instance declaration for (RegexMaker regex compOpt execOpt [Char]) In the expression: makeRegex "[+-]?[0-9]+" In the definition of `r': r = makeRegex "[+-]?[0-9]+" Prelude Text.Regex.Base.RegexLike>