Article: Writing Julia style multiple dispatch code in D

[data pulverizer via Digitalmars-d-announce]

On Wednesday, 30 August 2017 at 22:10:38 UTC, Jean-Louis Leroy 
wrote:
> On Wednesday, 30 August 2017 at 21:30:29 UTC, data pulverizer 
> wrote:
>> In the light of this I think your package just became more 
>> interesting to me.
>
> I think that your work and mine are complementary :-)

Here is one strange difference between inheriting from an 
interface and a class:

```
interface Animal{}
class Dog: Animal{}
class Cat: Animal{}


void main()
{
	Animal[] x;
	x ~= new Cat();
	x ~= new Dog();
	x ~= new Cat();
	writeln(typeid(x[0])); // Gives Animal
}
```

But if Animal is set to a class the typeid gives Cat, why does 
this happen? Does this mean that inheriting from an interface is 
not really polymorphism?