Fix E0589: Type Parameter Bound Not Satisfied for Const Generic

Sun, 26 Jul 2026 00:44:04 +0800

1. Symptoms

When Rust code triggers error E0589, the compiler produces output that clearly indicates a const generic bound mismatch. The diagnostic message typically follows this pattern:

error[E0589]: the trait bound `SomeType: Trait` is not satisfied
  --> src/main.rs:10:5
   |
10 |     fn generic_function<const N: usize where T: SomeTrait<N>>() {}
   |                                                       ^^^^^ required by this bound in `SomeTrait`

The error manifests in several common scenarios. First, when defining a function with const generic parameters that require trait bounds, the compiler rejects calls where the const value doesn’t satisfy those bounds. Second, struct definitions with const generic fields that impose trait constraints will fail compilation when instantiated incorrectly. Third, impl blocks for generic types may trigger E0589 when attempting to implement methods for type combinations that violate the declared constraints.

E0589 on ErrorVault — Developer Error Code Dictionary

Fix E0589: Type Parameter Bound Not Satisfied for Const Generic

1. Symptoms