{"ast_node_type":"function","tokens":[{"end":83,"kind":"keyword","start":0,"text":"//"}]}
                    // For all types reachable from the argument type in the fn sig
                for (arg_num, arg_def) in arg_defs.iter().enumerate() {
                    for inner_ty in arg_def.walk().filter_map(|arg| arg.as_type()) {