{"ast_node_type":"other","tokens":[{"end":105,"kind":"keyword","start":0,"text":"//"}]}
                        // generic params. It's inefficient to splice the `Substitution`s, so we may want
                        // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent
                        // that method to optionally take parent `Substitution` as we already know them at