src/test/ui/higher-rank-trait-bounds/hrtb-higher-ranker-supertraits.rs

   1 // Test a trait (`Bar`) with a higher-ranked supertrait.
   2
   3 trait Foo<'tcx>
   4 {
   5     fn foo(&'tcx self) -> &'tcx isize;
   6 }
   7
   8 trait Bar<'ccx>
   9     : for<'tcx> Foo<'tcx>
  10 {
  11     fn bar(&'ccx self) -> &'ccx isize;
  12 }
  13
  14 fn want_foo_for_some_tcx<'x,F>(f: &'x F)
  15     where F : Foo<'x>
  16 {
  17     want_foo_for_some_tcx(f);
  18     want_foo_for_any_tcx(f); //~ ERROR not satisfied
  19 }
  20
  21 fn want_foo_for_any_tcx<F>(f: &F)
  22     where F : for<'tcx> Foo<'tcx>
  23 {
  24     want_foo_for_some_tcx(f);
  25     want_foo_for_any_tcx(f);
  26 }
  27
  28 fn want_bar_for_some_ccx<'x,B>(b: &B)
  29     where B : Bar<'x>
  30 {
  31     want_foo_for_some_tcx(b);
  32     want_foo_for_any_tcx(b);
  33
  34     want_bar_for_some_ccx(b);
  35     want_bar_for_any_ccx(b); //~ ERROR not satisfied
  36 }
  37
  38 fn want_bar_for_any_ccx<B>(b: &B)
  39     where B : for<'ccx> Bar<'ccx>
  40 {
  41     want_foo_for_some_tcx(b);
  42     want_foo_for_any_tcx(b);
  43
  44     want_bar_for_some_ccx(b);
  45     want_bar_for_any_ccx(b);
  46 }
  47
  48 fn main() {}