The injector of AngularJS

[wonderfan]

• $injector is used to retrieve object instances as defined by
• {@link auto.$provide provider}, instantiate types, invoke methods,
• and load modules.

[wonderfan]

• In JavaScript calling toString() on a function returns the function definition. The definition
• can then be parsed and the function arguments can be extracted. NOTE: This does not work with
• minification, and obfuscation tools since these tools change the argument names.

[wonderfan]

• The {@link auto.$provide $provide} service has a number of methods for registering components
• with the {@link auto.$injector $injector}. Many of these functions are also exposed on
• {@link angular.Module}.

[wonderfan]

• An Angular service is a singleton object created by a service factory. These **service
• factories\ are functions which, in turn, are created by a service provider.
• The service providers are constructor functions. When instantiated they must contain a
• property called $get, which holds the service factory function.
• When you request a service, the {@link auto.$injector $injector} is responsible for finding the
• correct service provider, instantiating it and then calling its $get service factory
• function to get the instance of the service.