syntax_data: {"ast_node_type":"function","tokens":[{"end":80,"kind":"keyword","start":0,"text":"fn"}]}
source_snippet:     fn print(t: &PatternKind<'tcx>, f: &mut fmt::Formatter<'_>) -> fmt::Result {
context_before: impl<'tcx> IrPrint<PatternKind<'tcx>> for TyCtxt<'tcx> {
context_after:         match *t {