pub fn print_help(cmd: &Command, topic: Option<&str>) -> Result<()>Expand description
Entry point for the Commands::Help { topic } dispatch arm
AND the bare-help intercept in main.rs. Routes between everyday
/ advanced / topic surfaces and falls through to “use --help”
for verb names without a dedicated topic.
All output goes to stdout (this is help, not diagnostic). Returns
Ok(()) even for unknown topics; the printer surfaces the
suggestion text rather than erroring.