void initMouseEvent(
    in DOMString type, 
    in boolean canBubble, 
    in boolean cancelable, 
    in DOMWindow view, 
    in long detail, 
    in long screenX, 
    in long screenY, 
    in long clientX, 
    in long clientY, 
    in boolean ctrlKey, 
    in boolean altKey, 
    in boolean shiftKey, 
    in boolean metaKey, 
    in unsigned short button, 
    in EventTarget relatedTarget); 

readonly attribute boolean altKey; 

readonly attribute unsigned short button; 

readonly attribute long clientX; 

readonly attribute long clientY; 

readonly attribute boolean ctrlKey; 

readonly attribute Clipboard dataTransfer; 

readonly attribute Node fromElement; 

readonly attribute boolean metaKey; 

readonly attribute long offsetX; 

readonly attribute long offsetY; 

readonly attribute EventTarget relatedTarget; 

readonly attribute long screenX; 

readonly attribute long screenY; 

readonly attribute boolean shiftKey; 

readonly attribute Node toElement; 

readonly attribute long x; 

readonly attribute long y;