clap

Module _features

Source
Available on crate feature unstable-doc only.
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§Documentation: Feature Flags

Available compile-time feature flags

§Default Features
  • std: Not Currently Used. Placeholder for supporting no_std environments in a backwards compatible manner.
  • color: Turns on terminal styling of help and error messages. See Command::styles to customize this.
  • help: Auto-generate help output
  • usage: Auto-generate usage
  • error-context: Include contextual information for errors (which arg failed, etc)
  • suggestions: Turns on the Did you mean '--myoption'? feature for when users make typos.
§Optional features
  • deprecated: Guided experience to prepare for next breaking release (at different stages of development, this may become default)
  • derive: Enables the custom derive (i.e. #[derive(Parser)]). Without this you must use one of the other methods of creating a clap CLI listed above.
  • cargo: Turns on macros that read values from CARGO_* environment variables.
  • env: Turns on the usage of environment variables during parsing.
  • unicode: Turns on support for unicode characters (including emoji) in arguments and help messages.
  • wrap_help: Turns on the help text wrapping feature, based on the terminal size.
  • string: Allow runtime generated strings (e.g. with Str).
§Experimental features

Warning: These may contain breaking changes between minor releases.

  • unstable-v5: Preview features which will be stable on the v5.0 release