syntax_data: {"ast_node_type":"other","tokens":[{"end":42,"kind":"keyword","start":0,"text":"pat.map(|p|"}]}
source_snippet:         pat.map(|p| self.lower_pattern(p))
context_before:     fn lower_opt_pattern(&mut self, pat: Option<&'tcx hir::Pat<'tcx>>) -> Option<Box<Pat<'tcx>>> {
context_after:     }