overriding private interface methods

[Ali Çehreli]

On 10/23/2012 11:37 AM, Oleg wrote:
> Hello. How to override private methods?
>
> import std.stdio, std.conv;
>
> interface abcInterface
> {
> private double private_func();
> public final double func() { return private_func(); }
> }
>
> class abcImpl: abcInterface
> {
> override private double private_func() { return 3.14; } //#1
> }
>
> void main()
> {
> auto abc = new abcImpl;
> writeln( abc.func() );
> }
>
> This code generate error
> #1 Error: function inter.abcImpl.private_func cannot override a
> non-virtual function
>
> This private method (private_func) is 'private' because it must call
> only in final interface methods (func)

private member functions are not virtual by the design of the language. 
You have to make them 'protected', not private.

Ali