Key Concepts

Before we start, it would be good to introduce some core concepts used in uzi and
across this documentation.

Dependencies

A dependency is an object which other objects require (depend on).
In uzi a dependency is identified by it's type, a TypeVar or a DependencyMarker.

Providers

Providers define how a dependency is resolved. We use them to determine what
happens when a dependency is requested.
For example, they determine whether...
- to create a new instance of dependency x for each request or to share one instance. - to uses a predefined constant or proxy another existing dependency and provide its value instead.

Containers

Containers are mappings of dependencies to their providers. We use them to bind
dependencies to their providers.
To allow for better modularity, containers can also include other containers.

Scopes

These are isolated dependency resolution contexts created from a set of containers. Scopes assemble the dependency graphs of dependencies registered in their containers.

Injectors

These are isolated dependency injection contexts for our scopes. They are responsible for assembling the object graphs of dependencies in a given scope.