{"ast_node_type":"variable","tokens":[{"end":72,"kind":"keyword","start":0,"text":"if"}]}
                if let &ty::Closure(closure_def_id, _args) = ty.kind() {
            let is_capturing_closure = |ty: Ty<'tcx>| {
                    self.tcx.upvars_mentioned(closure_def_id.expect_local()).is_some()