optparse-applicative-dex-1.0.0: README.md

# optparse-applicative-dex


## Synopsis

Extra functions for working with optparse-applicative


## Description

optparse-applicative is a fantastic library

My usage of it has often used the same features wrapped in a `parseOpts`
function along with a version helper.

This package abstracts that code into a re-usable library, minimizing pasting
between projects.

In most CLI projects I almost always want:

- A header consisting of the program name and a short description
- A helper parser to provide -h, --help
- A version helper to respond to a --version option with shorter output than -h, --help
- Some additional usage info below the generated switch usage

The parseOpts' and parseOptsWithWidth functions in this library take a parser
and arguments for header, footer and the app version as generated by cabal and
do all these things automatically.

A simple example:

    {- # LANGUAGE OverloadedStrings #-}

    import Options.Applicative.Dex
    import Paths_your_app (version)

    data Options = Options { optA :: String , optB :: Bool }
      deriving Show

    parser :: Parser Options
    parser = Options
      <$> option str ( short 'a' <> metavar "STR" <> help "The a option, a string" )
      <*> switch ( short 'b' <> help "The b option, a switch")

    main :: IO ()
    main = do
      opts <- parseOpts' parser "header-info" "footer-info" version
      print opts


## Getting source

Source code is available from codeberg at the [optparse-applicative-dex](https://codeberg.org/dinofp/optparse-applicative-dex) project page.


## Contact

Dino Morelli <dino@ui3.info>