implimenting interface function by inheriting from other class

[Alexey]

On Saturday, 21 August 2021 at 20:35:43 UTC, Alexey wrote:
> Hello
> ```D
> interface Int
> {
>     void coolFunc();
> }
>
> class C1
> {
>     void coolFunc()
>     {
>         return;
>     }
> }
>
> class C2 : C1, Int
> {
>
> }
>
> void main()
> {
>     auto c = new C2;
> }
> ```
> dmd says it's not Ok:
> t.d(14): Error: class `t.C2` interface function `void 
> coolFunc()` is not implemented
>
> how to make dmd happy?

we're with friends tried similar thing with c++, java, groovy and 
go - worked ok.
```Java
interface Int
{
     public void coolFunc();
};

class C1
{
     public void coolFunc()
     {
         return;
     }
};

class C2 extends C1 implements Int
{

};


public class Main {

     public static void main(String args[])
     {
         Int c = new C2();
     }

}
```
```Groovy
interface Int
{
     void coolFunc()
}

class C1
{
     void coolFunc()
     {  print "hello" }
}

class C2 extends C1 implements Int
{ }

def printHello = { Int a -> a.coolFunc(); print " world: accept 
$Int" }

C2 a = new C2()
printHello(a)
```
```C++
class Int;
class C1;
class C2;

class Int
{
public:
     virtual void coolFunc() = delete;
};

class C1
{
public:
     virtual void coolFunc()
     {
         return;
     }
};

class C2 : public C1, public Int
{
public:
};

int main(int argc, char* argv[])
{
     auto c = new C2;
}
```
```Go
package main

import "fmt"

type Int interface {
   CoolFunc()
}

type C1 struct {
}

func (self *C1) CoolFunc() {
   fmt.Println("worked")
   return
}

type C2 struct {
   C1
}

func main() {

   var c Int

   c = new(C2)

   c.CoolFunc()

}
```