Evidence that two instances can be mixed.
Evidence that two instances can be mixed. Should normally be generated by macros.
Create an object that can be used to extend an instance with a trait implementation.
Create an object that can be used to extend an instance with an effectfully created trait implementation.
Create an object that can be used to extend an instance with a trait implementation that requires resources.
Zoom into one trait that is part of composed trait and modify its implementation.