Calling functions dynamicallyyy

hmmm. i’m trying to call a function on a clip, but i want to use a variable that i’m sending to the clip so that when the one function gets done it knows what to do next. i just have no idea of what the syntax would be. here’s a sample.

MovieClip.prototype.moveHere=function(x,y,spd,func){
this._x+=(x-this._x)/spd;
this._y+=(y-this._y)/spd;
if(Math.abs(this._x-x)<1 && Math.abs(this._y-y)<1){
this._x=x;
this._y=y;
trace(“done” add func);
if(func!=null){
//the function i want to call is
this.menu();
//but i want to use the variable func
//i think i need to use ['s but i have no idea the exact use. is it something like this below?
this[func add “()”];
}
this.onEnterFrame=null;
}
}

danke