deprecated_implement

Implementing '{0}' is deprecated.

The analyzer produces this diagnostic when a class annotated with @Deprecated.implement is used in the implements clause of a class or enum declaration. This annotation indicates that the ability to implement the annotated class is deprecated and will soon be removed. This change will likely be enforced by marking the class with interface, final, or sealed.

If the library p defines a class annotated with @Deprecated.implement:

@Deprecated.implement()
class C {}

Then, in any library other than p, the following code produces this diagnostic:

import 'package:p/p.dart';
​
class D implements C {}

Follow any directions found in the Deprecation.implement annotation. Otherwise, remove the implements clause.

class D {}