+data Flag
+ = Verbose | Version
+ | Help
+ | InputFile String | OutputFile String
+ | InputFormat String | OutputFormat String
+ deriving Show
+
+options :: [OptDescr Flag]
+options =
+ [ Option "v" ["verbose"] (NoArg Verbose) "More detailed output"
+ , Option "V" ["version"] (NoArg Version) "Display program version"
+ , Option "h" ["help"] (NoArg Help) "Display program version"
+ , Option "f" ["file"] (ReqArg InputFile "FILE") "Read from FILE"
+ , Option "w" ["output"] (ReqArg OutputFile "FILE") "Write to FILE"
+ , Option "i" ["informat"] (ReqArg InputFormat "FORMAT") "Parse dates in the given FORMAT"
+ , Option "o" ["outformat"] (ReqArg OutputFormat "FORMAT") "Output dates in the given FORMAT"
+ ]