I apologize if this has been touched on before, I'm not quite
sure what to search for and what I did try didn't bring anything
up.
Okay, so I'm learning D, using the D Tour flow and I went over
interfaces. Everything is making sense. I key in the example (as
I like to copy it by hand and then run it locally instead of
online) and I attempt to make a slight alteration. In the
previous example, with base classes, the main method begins with:
Any[] anys = [
new Integer(10),
new Float(3.1415f)
];
Which makes sense. Integer and Float in that example are both
inheriting from Any. So when doing the example with interfaces
where Dog and Cat both inherit from the interface Animal, I first
tried:
auto animals = [
new Dog,
new Cat
];
But got this error:
interfaces.d(51): Error: no property 'multipleNoise' for type
'object.Object'
Which implies (to me) the auto inferred object.Object, this makes
sense though. Without basic type inspection they're both classes
and object.Object is the most reasonable parent of them both.
Fine. I adjusted my code to better match the class example:
Animal[] animals = [
new Dog,
new Cat
];
Surely this works:
interfaces.d(47): Error: cannot implicitly convert expression
([new Dog, new Cat]) of type Object[] to Animal[]
Different _message_ but same issue. It's inferring Object[]. I've
told it explicitly that it's an Animal[], and both classes
inherit from Animal (as the solution and the example on the tour
page) demonstrate:
Animal dog = new Dog;
Animal cat = new Cat;
Animal[] animals = [dog, cat];
So they can be assigned to Animal fine, but even using them in an
expression tagged with Animal[] still produces an Object[] value.
Is this intentional? It feels unintuitive. I understand why auto
infers Object[] and that make sense, but if I'm using the actual
type (Animal[]) and can work the long way around to the same type
(the last example), why can't I do it via direct assignment to
Animal[]?
