syntax_data: {"ast_node_type":"other","tokens":[{"end":33,"kind":"keyword","start":0,"text":"impl<'tcx>"}]}
source_snippet: impl<'tcx> FmtPrinter<'_, 'tcx> {
context_before: // HACK(eddyb) limited to `FmtPrinter` because of `region_highlight_mode`.
context_after:     pub fn pretty_print_region(&mut self, region: ty::Region<'tcx>) -> Result<(), fmt::Error> {