Struct Command 

pub struct Command { /* private fields */ }

A single registered subcommand.

Build with Command::new and configure via the builder methods before passing to App::add_command.

Implementations

impl Command

pub fn new(name: impl Into<String>, handler: fn(&CommandContext)) -> Self

Creates a new command with the given name and handler function.

The handler receives a CommandContext containing the resolved flags and positional arguments for this invocation.

pub fn description(self, description: impl Into<String>) -> Self

Sets the short description shown in the app-level help listing.

pub fn usage(self, usage: impl Into<String>) -> Self

Sets the usage string shown when the user runs <cmd> --help.

Displayed as: <prog> <cmd> <usage>. For example, passing "<file> [--output <path>]" produces mytool convert <file> [--output <path>].

If omitted and the command has registered flags, a fallback of [options] is shown.

pub fn strict_flags(self, strict: bool) -> Self

Controls whether unknown flags cause a hard error or just a warning.

When true, passing an unrecognized flag prints an error and exits without calling the handler. When false (the default), a warning is printed and execution continues. Global flags are always considered known and never trigger this check.

pub fn flag(self, flag: Flag) -> Self

Registers a flag definition for this command.

Registered flags participate in alias resolution and appear in help text. Can be called multiple times to register multiple flags.