diff --git a/Source/Listener.as b/Source/Listener.as
index 4b2ccef..9b13e84 100644
--- a/Source/Listener.as
+++ b/Source/Listener.as
@@ -1,23 +1,28 @@
 class Listener {
-  static function helloWorld() {
-    trace("Hello, world!");
-  }
-  static function mkListenerHandler(obj: MovieClip) {
-    obj.listeners = new Array()
-    obj.mkListener = function(listener: Function) {
-      obj.listeners.push(listener)
+  static function mkListenerHandler(obj: MovieClip, types: Array) {
+    Utils.debug(arguments)
+    /* Utils.debug("Listener::mkListenerHandler", "obj = " + obj._name + "; types = " + types) */
+    obj.mkListener = function(type: String, listener: Function) {
+      Utils.assertDefined(obj, type + "Listeners")
+      obj[type + "Listeners"].push(listener)
     }
-    obj.onEnterFrame = function() {
-      for (var i in obj.listeners)
-        obj.listeners[i](obj)
+
+    for (var i in types) {
+      var type = types[i]
+      obj[type + "Listeners"] = new Array()
+      obj[type] = function() {
+        for (var j in obj[type + "Listeners"])
+          obj[type + "Listeners"][j](obj)
+      }
     }
   }
   static function spinRight(mc: MovieClip) {
     mc._rotation++
   }
   static function main() {
-    mkListenerHandler(_root.b)
+    Utils.debug(arguments)
+    mkListenerHandler(_root.b, new Array("onEnterFrame"))
 
-    _root.b.mkListener(spinRight)
+    _root.b.mkListener("onEnterFrame", spinRight)
   }
 }
diff --git a/Source/Prototype.fla b/Source/Prototype.fla
index eed568a..6b56b86 100644
Binary files a/Source/Prototype.fla and b/Source/Prototype.fla differ
diff --git a/Source/State.as b/Source/State.as
deleted file mode 100644
index bce056d..0000000
--- a/Source/State.as
+++ /dev/null
@@ -1,20 +0,0 @@
-class State {
-  static function run() {
-    _root.createEmptyMovieClip("target_mc", _root.getNextHighestDepth());
-    loadVariables("params.txt", _root.target_mc);
-    function checkParamsLoaded() {
-      if (_root.target_mc.done == undefined) {
-        trace("not yet.");
-      } else {
-        trace("finished loading. killing interval.");
-        trace("-------------");
-        for (var i in _root.target_mc) {
-          trace(i+": "+_root.target_mc[i]);
-        }
-        trace("-------------");
-        clearInterval(param_interval);
-      }
-    }
-    var param_interval: Number = setInterval(checkParamsLoaded, 100);
-  }
-}
diff --git a/Source/Unit.as b/Source/Unit.as
new file mode 100644
index 0000000..95ba794
--- /dev/null
+++ b/Source/Unit.as
@@ -0,0 +1,10 @@
+class Unit {
+  static function init(obj: Object) {
+    obj.ini = 0
+    obj.end = 5
+    obj.poi = 0
+    obj.ddg = 0
+    obj.att = 0
+    obj.def = 0
+  }
+}
diff --git a/Source/Utils.as b/Source/Utils.as
new file mode 100644
index 0000000..844cf16
--- /dev/null
+++ b/Source/Utils.as
@@ -0,0 +1,54 @@
+class Utils {
+  static function assert(bool: Boolean) {
+    if (bool)
+      return
+    error("Assert failed in " + nameOf(arguments.caller) + "!")
+  }
+  static function assertDefined(obj: Object, member: String) {
+    if (eval(String(obj) + "." + member) != undefined)
+      return
+    error("Assert failed in " + nameOf(arguments.caller) + " " + member + "is not member of " + obj._name + "!")
+  }
+  static function valueOr(maybeValue, defaultValue) {
+    return maybeValue == undefined ? defaultValue : maybeValue
+  }
+  static function debug(args: Object, msg) {
+    trace(nameOf(args.callee) + ": " + args + " " + valueOr(msg, ""))
+  }
+  static function warning(msg: String) {
+    trace("ERROR: " + msg)
+  }
+  static function error(msg: String) {
+    trace("ERROR: " + msg)
+  }
+  static var functionNameContexts = new Array(
+    Listener, Utils)
+  static function nameOf(func:Function): String {
+    for (var i in functionNameContexts) {
+      var obj: Function = functionNameContexts[i]
+      for (var prop in obj) {
+        if (functionNameContexts[i][prop] == func)
+          return prop;
+      }
+    }
+    return "anonymous function";
+  }
+  /* static function run() {
+    _root.createEmptyMovieClip("target_mc", _root.getNextHighestDepth());
+    loadVariables("params.txt", _root.target_mc);
+    function checkParamsLoaded() {
+      if (_root.target_mc.done == undefined) {
+        trace("not yet.");
+      } else {
+        trace("finished loading. killing interval.");
+        trace("-------------");
+        for (var i in _root.target_mc) {
+          trace(i+": "+_root.target_mc[i]);
+        }
+        trace("-------------");
+        clearInterval(param_interval);
+      }
+    }
+    var param_interval: Number = setInterval(checkParamsLoaded, 100);
+  } */
+}