syntax_data: {"ast_node_type":"variable","tokens":[{"end":75,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let name = ty::tls::with(|tcx| tcx.hir_name(self.var_path.hir_id));
context_before:     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
context_after:         write!(f, "UpvarId({:?};`{}`;{:?})", self.var_path.hir_id, name, self.closure_expr_id)