{"ast_node_type":"function","tokens":[{"end":100,"kind":"keyword","start":0,"text":"fn"}]}
    fn emit_span_lint(&self, sess: &Session, lint: &'static Lint, sp: Span, diag: BuiltinLintDiag) {
impl CfgMatchesLintEmitter for NodeId {
        sess.psess.buffer_lint(lint, sp, *self, diag);