diff --git a/source/Ox/js/Type.js b/source/Ox/js/Type.js
index f724bff4..9191beac 100644
--- a/source/Ox/js/Type.js
+++ b/source/Ox/js/Type.js
@@ -6,8 +6,8 @@ Ox.checkType <f> Throws a TypeError if a value is not of a given type
     val <*> Any value
     type <s|[s]> Type, or array of types
 @*/
-Ox.checkType = function(val, type) {
-    if (!Ox.contains(Ox.makeArray(type), Ox.typeOf(val))) {
+Ox.checkType = function(value, type) {
+    if (!Ox.contains(Ox.makeArray(type), Ox.typeOf(value))) {
         throw new TypeError();
     }
 };
@@ -19,8 +19,8 @@ Ox.isArguments <f> Tests if a value is an arguments "array"
     > Ox.isArguments((function() { return arguments; }()))
     true
 @*/
-Ox.isArguments = function(val) {
-    return Ox.typeOf(val) == 'arguments';
+Ox.isArguments = function(value) {
+    return Ox.typeOf(value) == 'arguments';
 };
 
 /*@
@@ -34,8 +34,8 @@ Ox.isArray <f> Tests if a value is an array
     > Ox.isArray({0: 0, length: 1})
     false
 @*/
-Ox.isArray = function(val) {
-    return Ox.typeOf(val) == 'array';
+Ox.isArray = function(value) {
+    return Ox.typeOf(value) == 'array';
 };
 
 /*@
@@ -45,8 +45,8 @@ Ox.isBoolean <f> Tests if a value is boolean
     > Ox.isBoolean(false)
     true
 @*/
-Ox.isBoolean = function(val) {
-    return Ox.typeOf(val) == 'boolean';
+Ox.isBoolean = function(value) {
+    return Ox.typeOf(value) == 'boolean';
 };
 
 /*@
@@ -56,8 +56,8 @@ Ox.isDate <f> Tests if a value is a date
     > Ox.isDate(new Date())
     true
 @*/
-Ox.isDate = function(val) {
-    return Ox.typeOf(val) == 'date';
+Ox.isDate = function(value) {
+    return Ox.typeOf(value) == 'date';
 };
 
 /*@
@@ -67,8 +67,8 @@ Ox.isElement <f> Tests if a value is a DOM element
     > Ox.isElement(document.createElement('a'))
     true
 @*/
-Ox.isElement = function(val) {
-    return Ox.endsWith(Ox.typeOf(val), 'element');
+Ox.isElement = function(value) {
+    return Ox.endsWith(Ox.typeOf(value), 'element');
 };
 
 /*@
@@ -156,8 +156,8 @@ Ox.isFunction <f> Tests if a value is a function
     > Ox.isFunction(/ /)
     false
 @*/
-Ox.isFunction = function(val) {
-    return Ox.typeOf(val) == 'function';
+Ox.isFunction = function(value) {
+    return Ox.typeOf(value) == 'function';
 };
 
 /*@
@@ -171,8 +171,8 @@ Ox.isInfinity <f> Tests if a value is positive or negative Infinity
     > Ox.isInfinity(NaN)
     false
 @*/
-Ox.isInfinity = function(val) {
-    return Ox.typeOf(val) == 'number' && !isFinite(val) && !Ox.isNaN(val);
+Ox.isInfinity = function(value) {
+    return Ox.typeOf(value) == 'number' && !isFinite(value) && !Ox.isNaN(value);
 };
 
 /*@
@@ -184,8 +184,8 @@ Ox.isInt <f> Tests if a value is an integer
     > Ox.isInt(0.5)
     false
 @*/
-Ox.isInt = function(val) {
-    return val === Math.floor(val);
+Ox.isInt = function(value) {
+    return value === Math.floor(value);
 };
 
 /*@
@@ -195,8 +195,8 @@ Ox.isNaN <f> Tests if a value is NaN
     > Ox.isNaN(NaN)
     true
 @*/
-Ox.isNaN = function(val) {
-    return val !== val;
+Ox.isNaN = function(value) {
+    return value !== value;
 }
 
 /*@
@@ -206,8 +206,8 @@ Ox.isNull <f> Tests if a value is <code>null</code>
     > Ox.isNull(null)
     true
 @*/
-Ox.isNull = function(val) {
-    return Ox.typeOf(val) == 'null';
+Ox.isNull = function(value) {
+    return Ox.typeOf(value) == 'null';
 };
 
 /*@
@@ -223,8 +223,8 @@ Ox.isNumber <f> Tests if a value is a number
     > Ox.isNumber(NaN)
     true
 @*/
-Ox.isNumber = function(val) {
-    return Ox.typeOf(val) == 'number';
+Ox.isNumber = function(value) {
+    return Ox.typeOf(value) == 'number';
 };
 
 /*@
@@ -242,8 +242,8 @@ Ox.isObject <f> Tests if a value is a an object
     > Ox.isObject(/ /)
     false
 @*/
-Ox.isObject = function(val) {
-    return Ox.typeOf(val) == 'object';
+Ox.isObject = function(value) {
+    return Ox.typeOf(value) == 'object';
 };
 
 /*@
@@ -261,8 +261,8 @@ Ox.isPrimitive <f> Tests if a value is a primitive (boolean, number or string)
     > Ox.isPrimitive({})
     false
 @*/
-Ox.isPrimitive = function(val) {
-    var type = Ox.typeOf(val);
+Ox.isPrimitive = function(value) {
+    var type = Ox.typeOf(value);
     return type == 'boolean' || type == 'number' || type == 'string';
 };
 
@@ -273,8 +273,8 @@ Ox.isRegExp <f> Tests if a value is a regular expression
     > Ox.isRegExp(/ /)
     true
 @*/
-Ox.isRegExp = function(val) {
-    return Ox.typeOf(val) == 'regexp';
+Ox.isRegExp = function(value) {
+    return Ox.typeOf(value) == 'regexp';
 };
 
 /*@
@@ -284,8 +284,8 @@ Ox.isString <f> Tests if a value is a string
     > Ox.isString('')
     true
 @*/
-Ox.isString = function(val) {
-    return Ox.typeOf(val) == 'string';
+Ox.isString = function(value) {
+    return Ox.typeOf(value) == 'string';
 };
 
 /*@
@@ -295,8 +295,8 @@ Ox.isUndefined <f> Tests if a value is undefined
     > Ox.isUndefined()
     true
 @*/
-Ox.isUndefined = function(val) {
-    return Ox.typeOf(val) == 'undefined';
+Ox.isUndefined = function(value) {
+    return Ox.typeOf(value) == 'undefined';
 };
 
 /*@
@@ -334,9 +334,14 @@ Ox.typeOf <f> Returns the type of a value
     > Ox.typeOf()
     'undefined'
 @*/
-Ox.typeOf = function(val) {
-    // Mobile Safari doesn't like null or undefined here
-    return val === null ? 'null'
-        : val === void 0 ? 'undefined'
-        : Object.prototype.toString.call(val).slice(8, -1).toLowerCase();
+Ox.typeOf = function(value) {
+    return Object.prototype.toString.call(value).slice(8, -1).toLowerCase();
 };
+if (Ox.typeOf() != 'undefined') {
+    // Handle Mobile Safari
+    Ox.typeOf = function(value) {
+        return value === null ? 'null'
+            : value === void 0 ? 'undefined'
+            : Object.prototype.toString.call(value).slice(8, -1).toLowerCase();
+    };
+}