Move a object on the x-axis with the mouse

 function Update () { 
  if (Get.MouseButton(1)){// if right mouse button is held down
       var mousePos = Input.mousePosition; 
  
       var wantedPos = Camera.main.ScreenToWorldPoint (Vector3 (mousePos.x, mousePos.y, 10)); 
  
       transform.position.x = wantedPos.x; 
    }
  }

Put this script on the item you want to be able to move. I use C# but I think this would work. This is untested script however, it should get you close. The link below is unity's basic scripting things, and they help go between java C# and boo. So if there is a function you can only seem to find in one, see if you can find JS's version through here

Mouse Input