If you want opt-in small vector optimization you could also use this crate written by the Servo team: https://github.com/servo/rust-smallvec https://github.com

If you want opt-in small vector optimization you could also use this crate written by the Servo team: https://github.com/servo/rust-smallvec https://github.com/servo/rust-smallvec You can take a look at their implementation. If I'm reading this correctly, access by index goes through deref, which matches on the self.data type: https://github.com/servo/rust-smallvec/blob/5758c25663da2421792078dd05624e31eee71db1/lib.rs#L737-L744 https://github.com/servo/rust-smallvec/blob/5758c25663da2421...