rust-traits-generics

Use Rust static dispatch with generics and `impl Trait` for zero-cost abstraction, and `dyn Trait` for heterogeneous collections needing runtime polymorphism. Static dispatch leverages generic bounds, while trait objects enable dynamic dispatch through vtables.

Design safe Rust abstractions by using traits with associated types to map concrete types to trait-level outputs, ensuring flexible APIs. Apply orphan and coherence rules to maintain safe abstraction layering and prevent conflicting implementations across library boundaries.

Your Rust trait fails as a trait object because it violates object safety. Avoid object-unsafe trait methods, such as those returning Self or requiring generic type parameters, which prevent the compiler from constructing valid vtables for `dyn Trait`.

The best way to choose between `impl Trait` and `dyn Trait` for a Rust library API is evaluating dispatch requirements. Prefer `impl Trait` for static dispatch and compile-time monomorphization, and `dyn Trait` for dynamic dispatch when exact concrete types vary at runtime.

Yes, you can use default methods with Rust traits to build ergonomic interfaces. Default methods provide baseline behavior that concrete implementors can override, reducing boilerplate while maintaining safe abstraction layering across application and library modules.