# Introduce Arc\ in Enum which impl PartialEq **URL:** \ **Category:** help\ **Created:** [November 16, 2023, 12:53pm UTC](https://users.rust-lang.org/t/introduce-arc-dyn-trait-in-enum-which-impl-partialeq/102649 "2023-11-16T12:53:24Z")\ **Posts on this page:** 1\ **Showing post:** 7
**Author:** ![2e71828](https://avatars.discourse-cdn.com/v4/letter/2/3e96dc/32.png) [@2e71828](https://users.rust-lang.org/u/2e71828)\ **Post date:** [November 16, 2023, 3:18pm UTC](https://users.rust-lang.org/t/introduce-arc-dyn-trait-in-enum-which-impl-partialeq/102649/7 "2023-11-16T15:18:10Z")
> [@Cerber-Ursi](#): > > ```rust > ^^^^^^^^ assignment requires that `'a` must outlive `'static` > > ``` > > Just _where_ is that assignment they are talking about?! I'm not sure where the assignment is, but the `'static` requirement is coming from the implicit lifetime in `dyn MyTrait`. This change [fixes the problem](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=f9b88b71c8e51a1e78c66bb8351fda27): ```diff -impl PartialEq for dyn MyTrait { +impl PartialEq for dyn MyTrait + '_ { ``` * * * _Edit:_ At least, it does for references. [The `Box` version is still broken](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=7d1a0fafce950d3ee23f711e53d03bf4): ```rust error[E0507]: cannot move out of `*__arg1_0` which is behind a shared reference --> src/main.rs:22:30 | 22 | * __self_0 == *__ arg1_0, | ^^^^^^^^^ move occurs because `*__arg1_0` has type `Box`, which does not implement the `Copy` trait ``` (and similarly for `Arc`) --- _[View the full topic](https://users.rust-lang.org/t/introduce-arc-dyn-trait-in-enum-which-impl-partialeq/102649)._