OptEnvConf

Status

Used in production in all my products and some companies.

Goals

• Parse command-line arguments, environment variables, and configuration values all together.
• Self-documenting parsers for correct-by-construction documentation
• Best-in-class command-line autocompletion
• Best-in-class errors
• Formatter-friendly API

Features

• Parsing
  • Argument: progname hello
  • Option: progname --file foo.txt
    • Long Option: progname --file foo.txt
    • Short Option: progname -f foo.txt
    • Equals-version of long option: progname --file=foo.txt
    • Shorthand-version of short option: progname -ffoo.txt
  • Switch: progname --verbose
    • Long switch: progname --verbose
    • Short switch: progname -v
• Documentation
  • --help
    • Global --help page
    • Per-command --help page
  • Generated --version command
  • Generated manpage
• Completion
  • Bash completion
  • Zsh completion
  • Fish completion
• Static settings check

Comparison to similar projects

	opt-env-conf	optparse-applicative	envparse	autodocodec
Applicative parsing	✔️	✔️	✔️	✔️
Parsing arguments	✔️	✔️	✖️	✖️
Parsing long options	✔️	✔️	✖️	✖️
Parsing short options	✔️	✔️	✖️	✖️
Parsing short-hand short options	✔️	✔️	✖️	✖️
Parsing short-hand long options	✔️	✔️	✖️	✖️
Parsing long switches	✔️	✔️	✖️	✖️
Parsing short switches	✔️	✔️	✖️	✖️
Parsing environment variables	✔️	✖️	✔️	✖️
Parsing configuration values	✔️	✖️	✖️	✔️
Generated global --help page	✔️	✔️	✖️	✖️
Coloured global --help page	✔️	✖️	✖️	✖️
Generated per-command --help page	✔️	✔️	✖️	✖️
Coloured per-command --help page	✔️	✖️	✖️	✖️
Generated --version command	✔️	✖️	✖️	✖️
Generated manpage	✔️	✖️	✖️	✖️
Helpful parse errors	✔️	✔️	✔️	✔️
Coloured parse errors	✔️	✖️	✖️	✖️
Generated manpage	✔️	✖️	✖️	✖️
Typo suggestions	🚧	✖️	✖️	✖️
Bash completion	✔️	✔️	✖️	✖️
Zsh completion	✔️	✔️	✖️	✖️
Fish completion	✔️	✔️	✖️	✖️
Static settings check	✔️	✖️	✖️	✖️

Example

The example application contains a fully worked example.

This example is part of the build in CI so you can rely on it being up-to-date.