Support AMD.

src/md2.js

@@ -1,5 +1,5 @@
 /*
- * js-md5 v0.2.0
+ * js-md5 v0.2.1
  * https://github.com/emn178/js-md2
  *
  * Copyright 2014-2015, emn178@gmail.com
@@ -10,10 +10,12 @@
 ;(function(root, undefined) {
   'use strict';
 
-  var NODE_JS = typeof(module) != 'undefined';
+  var NODE_JS = typeof process == 'object' && process.versions && process.versions.node;
   if(NODE_JS) {
     root = global;
   }
+  var COMMON_JS = !root.JS_MD2_TEST && typeof module == 'object' && module.exports;
+  var AMD = typeof define == 'function' && define.amd;
   var HEX_CHARS = '0123456789abcdef'.split('');
 
   var S = [ 0x29, 0x2E, 0x43, 0xC9, 0xA2, 0xD8, 0x7C, 0x01, 0x3D, 0x36, 0x54, 0xA1, 0xEC, 0xF0, 0x06, 0x13,
@@ -35,7 +37,7 @@
 
   var M = [], X = [], C = [];
 
-  var md2 = function(message, asciiOnly) {
+  var md2 = function(message) {
     var code, i, j, k, t, L = 0, loop = 1, B,
         index = 0, start = 0, bytes = 0, length = message.length;
 
@@ -140,9 +142,14 @@
     return hex;
   };
   
-  if(!root.JS_MD2_TEST && NODE_JS) {
+  if(COMMON_JS) {
     module.exports = md2;
-  } else if(root) {
+  } else {
+    if(AMD) {
+      define(function() {
+        return md2;
+      });
+    }
     root.md2 = md2;
   }
 }(this));