Dart 3 examples

main.dart

// ------- Different class declarations -------
base class BaseClassExample {}

mixin class MiximClassExample {}

final class FinalClassExample {}


// ------- Different class usages -------

// This doesn't work but that's expected
class Example extends BaseClassExample {}

// Why does this work?
base class Example1 extends BaseClassExample {}
final class Example2 extends BaseClassExample {}
sealed class Example3 extends BaseClassExample {}

// Why does these work?
class Example4 implements MiximClassExample {}
class Example5 extends MiximClassExample {}

// Shouldn't these failures just happen outside the current library?
class Example6 implements FinalClassExample{}
class Example7 extends FinalClassExample{}

// Why does doing this work?
base class Example8 implements FinalClassExample{}
final class Example9 extends FinalClassExample{}
sealed class Example10 extends FinalClassExample{}