Command-line argument parsing library for Haskell programs

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Stackage Nightly 2024-04-18:
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BSD-3-Clause licensed and maintained by Bart Massey
This version can be pinned in stack with:parseargs-,945

Module documentation for

  • System
    • System.Console
      • System.Console.ParseArgs
Depends on 2 packages(full list with versions):


Command-line argument parsing for Haskell programs
Bart Massey [email protected]

This library provides System.Console.Parseargs, a module to assist in argument parsing for Haskell stand-alone command line programs.

The package provides a Haskell command-line argument “parser”. You supply a specification of the arguments to your command-line program; parseargs reads the arguments and checks that they meet your spec. It then fills in a data structure that captures the relevant data, from which parsed arguments can be extracted as needed. See the Haddock documentation for the gory details.

I have used this code with ghc 6 and 7 on Linux. It is a fairly standard Hackage-ready package, to the extent I know how to construct such.

The 0.1.2 release includes a typeclass for argument types for easier use.

The 0.1.3 release includes more uniform and usable error handling.

The various 0.1.3.x point releases include bug fixes and various extra-minor enhancements. See the Git log.

The 0.1.4 release includes the ability to mix optional and required positional arguments.

The 0.1.5 release includes the “soft dash” option, giving the ability to allow positional arguments to begin with a dash if possible.

The release fixes some warnings and stuff.

The release fixes some missing documentation.

This library is not what I set out to build. It definitely could also use some work. However, I use it all the time for writing little programs. I thought others might find it useful, and I also have released other code that depends on it, so I put it out there.

Have fun with it, and let me know if there are problems.

This code is released under a “3-clause BSD” license. Please see the file COPYING in this distribution for license terms.