interface function declarations to be used internally

Question

Is it possible to use externally declared interface functions internally in a smart contract?
i.e. say contract A inherits interface A, would contract A be able to implement the functions from interface A in an internal fashion (declaring a function as internal) not allowing the public to call it?

Answer 1

An interface cannot contain functions declared as internal or public, only as external.

If you can declare your interface as contract and will not have that limitation.

contract Bob {
    function foo() internal;
}


contract Mar is Bob {

    function vote() public {
        foo();
    }

    function foo() internal {
    }
}