Sorry for the weird title.
I dealt with interfaces and abstract classes and came accross a behavior I didn't expect. Can someone clarify if this behavior is wanted?

I have multiple interfaces, were an abstract class inherits from. The abstract class however, just defines part of the functions to be abstract and does not implement the others. A concrete class then finally derives from the abstract class.

So I as a user would expect that the concrete class implements all methods defined in the interfaces. However, this seems to not be the case. The following code compiles just fine, even if baz() was never implemented. Calling the baz() function on a Concrete object causes the program to crash.

interface A {
	void foo();
}

interface B {
	void baz();
}

class Abstract : A, B {
	abstract void foo();
}

class Concrete : Abstract {
	override void foo()	{ writeln("foo"); }
}

On Wednesday, 24 March 2021 at 08:22:51 UTC, zack wrote:
> Sorry for the weird title.
> I dealt with interfaces and abstract classes and came accross a behavior I didn't expect. Can someone clarify if this behavior is wanted?
>
> [...]

that is possibly https://issues.dlang.org/show_bug.cgi?id=19192 which has a PR https://github.com/dlang/dmd/pull/12302 in review, which should be merged very soon.