AS3 compiler error: 1182 package cannot be used as value

programming flash
1

This is my first attempt at creating (actually modifying to suit my need) a class. This is the first bit:

package
 { 
    import flash.display.Sprite;
    import flash.text.*;
    
    public class TextBox extends Sprite    
    { 
        private var _xPos:Number;
        private var _yPos:Number;
        private var _wide:Number;
        private var _high:Number; 

        private var _background:Sprite;
        private var _textBackground:Sprite; 
        private var _tf:TextField;
        private var _tfFormat:TextFormat;

        public function MyComponent(x:Number = 0, 
                                    y:Number = 0, 
                                    w:Number = 0, 
                                    h:Number = 0):void 
        {
            _xPos = x;
            _yPos = y;
            _wide = w;
            _high = h;
            
            createChildren();
            drawThings();
        }

The compiler give the error on

var overlay:TextBox = new TextBox();

but why?