Function document 

pub fn document(command: Command) -> Document

Available on crate feature help only.

Build the help document of a Clap command.

The document holds the usage line, the about text, a Commands section, an Arguments section, and one section per option help heading (Options when an option names none). ctl-core’s -h/--help flag and help subcommand are added, and the command is built first, so derived values such as the version flag are present. Hidden subcommands, arguments, and options are left out.

Panics

In a debug build, panics when Clap’s debug_assert finds an invalid command definition, as parser::verify does.