fn fold_pattern(&mut self, pat: &Pattern<'tcx>) -> Pattern<'tcx> {
debug!("fold_pattern {:?} {:?} {:?}", pat, pat.ty.sty, pat.kind);
match (&pat.ty.sty, &*pat.kind) {
fn fold_pattern(&mut self, pat: &Pattern<'tcx>) -> Pattern<'tcx> {
debug!("fold_pattern {:?} {:?} {:?}", pat, pat.ty.sty, pat.kind);
match (&pat.ty.sty, &*pat.kind) {