diff --git a/source/Ox/js/Core.js b/source/Ox/js/Core.js
index ca001303..a05539e0 100644
--- a/source/Ox/js/Core.js
+++ b/source/Ox/js/Core.js
@@ -259,9 +259,9 @@ Ox.loop = function() {
         i;
     try {
         for (i = start; step > 0 ? i < stop : i > stop; i += step) {
+            // fn(i);
             if (fn(i) === false) {
-                console.warn('Returning false in Ox.loop is deprecated.')
-                break;
+                throw new Error('Returning false in Ox.loop is deprecated.');
             }
         }
     } catch(e) {
@@ -272,47 +272,6 @@ Ox.loop = function() {
     return i;
 };
 
-Ox._loop = function() {
-    var type = Ox.makeArray(arguments).map(function(arg) {
-            return Ox.typeOf(arg);
-        }),
-        fnIndex = type.indexOf('function'),
-        callbackIndex = type.lastIndexOf('function'),
-        nIndex = callbackIndex - 1,
-        hasStart = type[1] == 'number',
-        hasStep = hasStart && type[2] == 'number',
-        hasCallback = fnIndex != callbackIndex,
-        hasN = hasCallback && type[nIndex] == 'number',
-        start = hasStart ? arguments[0] : 0,
-        stop = arguments[hasStart ? 1 : 0],
-        step = hasStep ? arguments[2] : (start <= stop ? 1 : -1),
-        fn = arguments[fnIndex],
-        n = hasN ? arguments[nIndex] / step : 1,
-        callback = hasCallback ? arguments[callbackIndex] : null;
-    function loop(start_, stop_, callback_) {
-        var i, isFalse;
-        for (i = start_; step > 0 ? i < stop_ : i > stop_; i += step) {
-            if (isFalse = fn(i) === false) {
-                break;
-            }
-        }
-        callback_ && callback_(i, !isFalse);
-        return i;
-    }
-    function next(start_) {
-        setTimeout(function() {
-            loop(start_, Math.min(start_ + n, stop), function(i, ret) {
-                (ret && i < stop ? next : callback)(i);
-            });
-        });
-    }
-    if (hasCallback) {
-        next(start);
-    } else {
-        return loop(start, stop);
-    }
-};
-
 /*@
 Ox.print <f> Prints its arguments to the console
     (arg, ...) -> <s> String