Example of partial implementations

Main.hx

package ;
import tink.lang.Cls;

class Main {
	static function main() {
		var foods = 'cookie,soup,banana'.split(',');
		var eaters = [new Human(), new CookieMonster(), new Robot()];
		for (e in eaters)
			for (f in foods)
				e.eat(f);
		$type(eaters);// Array<Mouth>
	}
}
interface Mouth implements Cls {
	public function eat(food:String):Void {
		trace('Yummy, what a delicious ' + food);
	}
}
interface SweetTooth implements Mouth {
	public function eat(food:String):Void {
		if (food == 'cookie') trace('Cookiiiiieeee!!!!');
		else trace('ewwww!!!');
	}
}

class Human implements Mouth {
	public function new() {}
}
class CookieMonster implements SweetTooth {
	public function new() {}
}
class Robot implements Mouth {	
	public function new() {}
	public function eat(food:String):Void {
		trace('Robots do not eat ' + food);
	}
}

Awesome thanks!