src/test/ui/impl-trait/projection.rs

   1 // build-pass
   2 // needs to be build-pass, because it is a regression test for a mir validation failure
   3 // that only happens during codegen.
   4
   5 struct D;
   6
   7 trait Tr {
   8     type It;
   9     fn foo(self) -> Option<Self::It>;
  10 }
  11
  12 impl<'a> Tr for &'a D {
  13     type It = ();
  14     fn foo(self) -> Option<()> { None }
  15 }
  16
  17 fn run<F>(f: F)
  18     where for<'a> &'a D: Tr,
  19           F: Fn(<&D as Tr>::It),
  20 {
  21     let d = &D;
  22     while let Some(i) = d.foo() {
  23         f(i);
  24     }
  25 }
  26
  27 fn main() {
  28     run(|_| {});
  29 }