A trait to represent the abstract idea of a container. The only concrete knowledge known is the number of elements contained within.

A map is a key-value store where values may be looked up by their keys. This trait provides basic operations to operate on these stores.

A trait to represent mutable containers

This trait provides basic operations to modify the contents of a map.

This trait represents actions which can be performed on sets to mutate them.

A set is a group of objects which are each distinct from one another. This trait represents actions which can be performed on sets to iterate over them.