Re: Opt-out polymorphism?

[Steven Schveighoffer]

On Sun, 13 Feb 2011 16:34:04 -0500, Sean Eskapp <eatingstap...@gmail.com>  
wrote:

Is there a way to specify that a function is nonvirtual, but can still be
"overriden" in base classes? e.g.
class A
{
    void foo()
    {
        writeln("A");
    }
}

class B : A
{
    void foo()
    {
        writeln("B");
    }
}

void main()
{
    (new A).foo();
    (new B).foo();
}

Should output:
A
B

Is there a way to do this?

You can make them templates.  Templates are not final, and are not virtual.

e.g.: (untested)


class A
{
    void foo()()
    {
        writeln("A");
    }
}

class B : A
{
    void foo()()
    {
        writeln("B");
    }
}

The huge *huge* drawback is this:

A a = new B;
a.foo(); // outputs "A"

So I don't see a very common use case for this.

-Steve