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f5c8e0989d
## Inheritance Semantics:
Decorators:
1) list the decorators of the class and its parents in the ancestor first order
2) only use the last decorator of each kind (e.g. @Component / ...)
Constructor parameters:
If a class inherits from a parent class and does not declare
a constructor, it inherits the parent class constructor,
and with it the parameter metadata of that parent class.
Lifecycle hooks:
Follow the normal class inheritance model,
i.e. lifecycle hooks of parent classes will be called
even if the method is not overwritten in the child class.
## Example
E.g. the following is a valid use of inheritance and it will
also inherit all metadata:
```
@Directive({selector: 'someDir'})
class ParentDirective {
constructor(someDep: SomeDep) {}
ngOnInit() {}
}
class ChildDirective extends ParentDirective {}
```
Closes #11606
Closes #12892
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| .. | ||
| animation | ||
| change_detection | ||
| debug | ||
| di | ||
| dom | ||
| facade | ||
| linker | ||
| metadata | ||
| reflection | ||
| testability | ||
| util | ||
| zone | ||
| application_init_spec.ts | ||
| application_module_spec.ts | ||
| application_ref_spec.ts | ||
| component_fixture_spec.ts | ||
| dev_mode_spec.ts | ||
| directive_lifecycle_integration_spec.ts | ||
| error_handler_spec.ts | ||
| fake_async_spec.ts | ||
| forward_ref_integration_spec.ts | ||
| spies.ts | ||
| testing_internal_spec.ts | ||