///测试代码   
function aaaa(a){   
    alert(a);   
}   
  
function aaaaa(a,b,c){   
    alert(a + b + c);   
}   

var __sto = setTimeout;   
yu= function(callback,timeout,param){   
    var args = Array.prototype.slice.call(arguments,2);   
    var _cb = function(){   
        callback.apply(null,args);   
    }   
    __sto(_cb,timeout);   
}

var a = "a";   
yu(aaaa,1000,a);   
yu(aaaaa,2000,a,6,7);