type rename … func (r *rename) Name() string { … } func (r *rename) Parent() string { … } func (r *rename) Usage() string { … } func (r *rename) ShortHelp() string { … } func (r *rename) DetailedHelp(f *flag.FlagSet) { … } // Run renames the specified identifier and either; // - if -w is specified, updates the file(s) in place; // - if -d is specified, prints out unified diffs of the changes; or // - otherwise, prints the new versions to stdout. func (r *rename) Run(ctx context.Context, args ...string) error { … }