[vashurin]

function Construct1(x,y){
	var coords_x=x;
	var coords_y=y;
	this.pub=function(){
	alert(coords_x-coords_y);
	}
	}
Construct1.prototype.say=function(){
	alert(coords_x - coords_y);
	}	
obj=new Construct1(13,-9);
obj.pub();//good!!!
obj.say()//coords_x is not defined

function Construct1(x,y){
	this.coords_x=x;
	this.coords_y=y;
	this.pub=function(){
	alert(this.coords_x-this.coords_y);
	}
	}
Construct1.prototype.say=function(){
	alert(this.coords_x  -  this.coords_y);
	}	
obj=new Construct1(13,-9);
obj.pub();//good!!!
obj.say()//coords_x is not defined

this