Re: nested class inheritance

[Paulo Pinto]

Am 14.07.2012 11:45, schrieb Gor Gyolchanyan:

On Sat, Jul 14, 2012 at 1:36 PM, Guillaume Chatelet
<chatelet.guilla...@gmail.com <mailto:chatelet.guilla...@gmail.com>> wrote:

    On 07/13/12 21:41, Andrei Alexandrescu wrote:
     > On 7/13/12 3:36 PM, Gor Gyolchanyan wrote:
     >> The initial question was: why does DMD 2.059 reject this if this
    makes
     >> sense?
     >> It's not even a new feature. It's a (possibly) new (and apparently
     >> sensible) use case of an existing feature.
     >
     > I think the simple answer is there was no provision for it. The
    feature
     > copies the Java feature, and I don't think Java has something
    like what
     > you defined.
     >
     > Andrei
     >

    class Fruit {
         class Seed {
         }
    }

    class Apple extends Fruit {
         class AppleSeed extends Fruit.Seed {
             Apple getOuter() {
                 return Apple.this;
             }
         }
    }

    class Main {
         public static void main(String[] args) {
             final Apple apple = new Apple();
             final Apple.AppleSeed appleSeed = apple.new AppleSeed();
             assert (appleSeed instanceof Fruit.Seed);
             assert (apple == appleSeed.getOuter());
             assert (appleSeed.getOuter() instanceof Apple);
             assert (appleSeed.getOuter() instanceof Fruit);
         }
    }

    This is valid Java code actually and I agree with Gor I would have
    expected it to work with D.

    Guillaume


I didn't even know this worked in Java. This means, that nested classed
in D can't translate nested classed in Java after all.

This usually comes up in certification and interview questions.