getOpt package:base

getOpt :: ArgOrder a -> [OptDescr a] -> [String] -> ([a], [String], [String])
base System.Console.GetOpt
Process the command-line, and return the list of values that matched (and those that didn't). The arguments are:
  • The order requirements (see ArgOrder)
  • The option descriptions (see OptDescr)
  • The actual command line arguments (presumably got from getArgs).
getOpt returns a triple consisting of the option arguments, a list of non-options, and a list of error messages.
module System.Console.GetOpt
base
This module provides facilities for parsing the command-line options in a standalone program. It is essentially a Haskell port of the GNU getopt library.
getOpt' :: ArgOrder a -> [OptDescr a] -> [String] -> ([a], [String], [String], [String])
base System.Console.GetOpt
This is almost the same as getOpt, but returns a quadruple consisting of the option arguments, a list of non-options, a list of unrecognized options, and a list of error messages.