Scala constructor, logic and inheritance

i have a question about scala and logic in constructor. Lets say i have a following code:

class A(val x:Int) {...whatever...}

cla开发者_如何转开发ss B(val y:String) extends A(IntValueDerivedFrom_y)

Now, how would i derive some value from y and passed it to constructor of class A? I hope it's understandable what i ask about.

Thanks for the answers!

Not sure I understand. You may do

class B(val y: String) extends A(f(y))

f(y) stands for any expression where y appears. For instance, Integer.parseInt(y)

This is close to java code

class B extends A {
   public B(String y) {
       super(Integer.parseInt(y));
   }
}

Is that what you wanted?