tests/ui/lazy-type-alias-impl-trait/opaque_vs_opaque.rs

   1 // check-pass
   2
   3 fn main() {}
   4
   5 fn filter_fold<T, Acc, PRED: FnMut(&T) -> bool, FOLD: FnMut(Acc, T) -> Acc>(
   6     mut predicate: PRED,
   7     mut fold: FOLD,
   8 ) -> impl FnMut(Acc, T) -> Acc {
   9     move |acc, item| if predicate(&item) { fold(acc, item) } else { acc }
  10 }