tests/ui/regions/regions-outlives-projection-container-wc.rs

   1 // Test that we are imposing the requirement that every associated
   2 // type of a bound that appears in the where clause on a struct must
   3 // outlive the location in which the type appears, even when the
   4 // constraint is in a where clause not a bound. Issue #22246.
   5
   6 #![allow(dead_code)]
   7
   8 pub trait TheTrait {
   9     type TheAssocType;
  10 }
  11
  12 pub struct TheType<'b> {
  13     m: [fn(&'b()); 0]
  14 }
  15
  16 impl<'b> TheTrait for TheType<'b> {
  17     type TheAssocType = &'b ();
  18 }
  19
  20 pub struct WithAssoc<T> where T : TheTrait {
  21     m: [T; 0]
  22 }
  23
  24 fn with_assoc<'a,'b>() {
  25     // For this type to be valid, the rules require that all
  26     // associated types of traits that appear in `WithAssoc` must
  27     // outlive 'a. In this case, that means TheType<'b>::TheAssocType,
  28     // which is &'b (), must outlive 'a.
  29
  30     let _: &'a WithAssoc<TheType<'b>> = loop { };
  31     //~^ ERROR lifetime may not live long enough
  32 }
  33
  34 fn main() {
  35 }