This is a tracking issue for the RFC "Associated type bounds of form MyTrait<AssociatedType: Bounds>" (rust-lang/rfcs#2289). The feature gate is #![feature(associated_type_bounds)].

Steps:

• Implement the RFC - Implementation of RFC 2289 (associated_type_bounds) #57428
• Adjust documentation (see instructions on forge)
• Stabilization PR (see instructions on forge)

Unresolved questions:

• Does allowing this for dyn trait objects introduce any unforeseen issues? This can be resolved during stabilization.

  • Use for trait objects has been forbidden in Remove support for associated_type_bound nested in dyn types #120719

• Resolve exact desugaring in the context of putting bounds on an associated type of a trait. See discussion in the RFC.

• Consider nested lifetimes, https://gist.github.com/Centril/b0e62d31d4ae1849535c3e506e1fad64.

TODO:

• Extend with tests in Implementation of RFC 2289 (associated_type_bounds) #57428 (comment).

• associated_type_bounds: errors with ambiguous associated type #61752