{"ast_node_type":"other","tokens":[{"end":67,"kind":"keyword","start":0,"text":"self.dcx().emit_err(errors::UnknownTokenStart"}]}
                    self.dcx().emit_err(errors::UnknownTokenStart {
                        unicode_chars::check_for_substitution(self, start, c, repeats + 1);
                        span: self.mk_sp(start, self.pos + Pos::from_usize(repeats * c.len_utf8())),