| // @dart = 2.9 | |
| class A { | |
| void foo() {} | |
| } | |
| abstract class I { | |
| void foo([a]); | |
| } | |
| abstract class B extends A { | |
| void foo([a]); | |
| } | |
| class C extends B {} | |
| class D extends A implements I {} | |
| abstract class E extends A implements I {} | |
| class F extends E {} | |
| main() {} |