Optparse-applicative is a haskell library for parsing options on the command
line, providing a powerful applicative interface for composing these options.
optparse-applicative takes care of reading and validating the arguments passed
to the command line, handling and reporting errors, generating a usage line, a
comprehensive help screen, and enabling context-sensitive bash completions.
See the included README for detailed instructions and examples, which is also
available on github <https://github.com/pcapriotti/optparse-applicative>.