Trait Variance 

pub trait Variance: Default + Sealed { }

A sealed trait implemented by Covariant<T>, Contravariant<T>, and Invariant<T>.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<T: ?Sized> Variance for Contravariant<T>

impl<T: ?Sized> Variance for Covariant<T>

impl<T: ?Sized> Variance for Invariant<T>