error[E0309]: the associated type `<Left as HasChildrenOf>::T` may not live long enough
  --> $DIR/issue-86787.rs:23:5
   |
LL | /     type TRef<'a>
LL | |
LL | |
LL | |     where
LL | |     <Left as HasChildrenOf>::T: 'a,
LL | |     <Right as HasChildrenOf>::T: 'a
   | |                                    - help: consider adding a where clause: `, <Left as HasChildrenOf>::T: 'a`
LL | |     = Either<&'a Left::T, &'a Right::T>;
   | |________________________________________^ ...so that the definition in impl matches the definition from the trait

error[E0309]: the associated type `<Right as HasChildrenOf>::T` may not live long enough
  --> $DIR/issue-86787.rs:23:5
   |
LL | /     type TRef<'a>
LL | |
LL | |
LL | |     where
LL | |     <Left as HasChildrenOf>::T: 'a,
LL | |     <Right as HasChildrenOf>::T: 'a
   | |                                    - help: consider adding a where clause: `, <Right as HasChildrenOf>::T: 'a`
LL | |     = Either<&'a Left::T, &'a Right::T>;
   | |________________________________________^ ...so that the definition in impl matches the definition from the trait

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0309`.