pub trait Subcommand: FromArgMatches + Sized {
    fn augment_subcommands(app: App<'_>) -> App<'_>;
fn augment_subcommands_for_update(app: App<'_>) -> App<'_>;
fn has_subcommand(name: &str) -> bool; }
Expand description

Parse a sub-command into a user-defined enum.

Implementing this trait lets a parent container delegate subcommand behavior to Self. with:

  • #[clap(subcommand)] field: SubCmd: Attribute can be used with either struct fields or enum variants that impl Subcommand.
  • #[clap(flatten)] Variant(SubCmd): Attribute can only be used with enum variants that impl Subcommand.

See the derive reference for attributes and best practices.

NOTE: Deriving requires the derive feature flag


struct Args {
   action: Action,

enum Action {

Required methods

Append to App so it can instantiate Self.

See also IntoApp.

Append to App so it can update self.

This is used to implement #[clap(flatten)]

See also IntoApp.

Test whether Self can parse a specific subcommand

Implementations on Foreign Types