28             leading_colon: None,  in from()
72             None => false,  in is_ident()
91             None  in get_ident()
125             arguments: PathArguments::None,  in from()
142         None,
152         PathArguments::None  in default()
159             PathArguments::None => true,  in is_empty()
167             PathArguments::None => true,  in is_none()
336                             PathArguments::None | PathArguments::AngleBracketed(_) => true,  in parse()
344                             PathArguments::None => None,  in parse()
371                                 PathArguments::None => None,  in parse()
423                 qself: None,  in const_argument()
657                 None  in qpath()
678                 None => {  in qpath()
683                     (0, None, path)  in qpath()
696             Ok((None, path))  in qpath()
767             PathArguments::None => {}  in print_path_arguments()
895         conditionally_print_turbofish(tokens, &None, style);  in print_parenthesized_generic_arguments()
910             None => {  in print_qpath()