Memoizing Event Register Functions

gistfile1.js

/***********************************************************************
  Initial Version 
************************************************************************/

var eventOn = function(type,fn){ win.addEventListener ?              
                     win.addEventListener(type,fn,false) :                  
                     win.attachEvent('on'+type,fn)},
    eventOff = function(type,fn){ win.removeEventListener ?
                     win.removeEventListener(type,fn,false) : 
                     win.detachEvent('on'+type,fn)},

/***********************************************************************
  Memoization Version 
************************************************************************/

var eventOn, eventOff;
if (win.addEventListener) {
   eventOn  = function(type,fn){win.addEventListener(type,fn,false)}
   eventOff = function(type,fn){win.removeEventListener(type,fn,false)}
}
else {
   eventOn  = function(type,fn){win.attachEvent('on'+type,fn)};
   eventOff = function(type,fn){win.detachEvent('on'+type,fn)};
}

less compact but yeah