{"ast_node_type":"other","tokens":[{"end":90,"kind":"keyword","start":0,"text":"self.still_bound_vars.push(ty::BoundVariableKind::Region(old_bound.kind));"}]}
                self.still_bound_vars.push(ty::BoundVariableKind::Region(old_bound.kind));
                let var = ty::BoundVar::from_usize(self.still_bound_vars.len());
                let mapped = ty::Region::new_bound(