//definition: 1
public class MyClass{

    private MyObject obj = new MyObject();
    private String   str = "hello world";

    // constructor
    public MyClass(){

    }
}

// definition: 2
public class MyClass{

    private MyObject obj = null;
    private String   str = null;

    // constructor
    public MyClass(){
        obj = new MyClass();
        str = "HelloWorld";
    }
}

public class Foo
{
    private var bar:Array = [1, 2, 3];
    private var baz:Array = bar.concat([4, 5, 6]);
}

public class Foo
{
    private var baz:Array = bar.concat([4, 5, 6]);
    private var bar:Array = [1, 2, 3];
}