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diff --git a/packages/vold-utils/lib/memoize.js b/packages/vold-utils/lib/memoize.js
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+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MIT/X11 License
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * Contributor(s):
+ *   Nils Maier <MaierMan@web.de>
+ *   Erik Vold <erikvvold@gmail.com>
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+"use strict";
+
+/**
+ * Decorate a function with a memoization wrapper, with a limited-size cache
+ * to reduce peak memory utilization.
+ *
+ * The memoized function may have any number of arguments, but they must be
+ * be serializable.  It's safest to use this only on functions that accept
+ * primitives.
+ *
+ * A memoized function is not thread-safe, but so is JS,  nor re-entrant-safe!
+ *
+ * @usage var foo = Scriptish_memoize(function foo(arg1, arg2) { ... complex operation ... });
+ * @param {Function} func The function to be memoized
+ * @param {Number} limit Optional. Cache size (default: 100)
+ * @param {Number} num_args Options. Number of arguments the function expects (default: func.length)
+ * @return {Function} Memoized function
+ */
+exports.memoize = function memoize(func, limit, num_args) {
+  limit = limit || 100;
+  num_args = num_args || func.length;
+
+  var cache = Object.create(null);
+  var keylist = [];
+  var args = [];
+  var key, result;
+
+  switch (num_args) {
+  case 0:
+    throw new Error("memoize does not support functions without arguments");
+  case 1:
+    return function memoize_one_arg(a) {
+      key = a.toString();
+
+      if (key in cache)
+        return cache[key];
+
+      result = func.call(null, a);
+      cache[key] = result;
+      if (keylist.push(key) > limit)
+        delete cache[keylist.shift()];
+      return result;
+    };
+  case 2:
+    return function memoize_two_args(a, b) {
+      args[0] = a; args[1] = b;
+      key = JSON.stringify(args);
+      args.length = 0;
+
+      if (key in cache)
+        return cache[key];
+
+      var result = func.call(null, a, b);
+      cache[key] = result;
+      if (keylist.push(key) > limit)
+        delete cache[keylist.shift()];
+      return result;
+    };
+  case 3:
+    return function memoize_three_args(a, b, c) {
+      args[0] = a; args[1] = b; args[2] = c;
+      key = JSON.stringify(args);
+      args.length = 0;
+
+      if (key in cache)
+        return cache[key];
+
+      var result = func.call(null, a, b, c);
+      cache[key] = result;
+      if (keylist.push(key) > limit)
+        delete cache[keylist.shift()];
+      return result;
+    };
+
+  case 4:
+    return function memoize_four_args(a, b, c, d) {
+      args[0] = a; args[1] = b; args[2] = c; args[3] = d;
+      key = JSON.stringify(args);
+      args.length = 0;
+
+      if (key in cache)
+        return cache[key];
+
+      var result = func.call(null, a, b, c, d);
+      cache[key] = result;
+      if (keylist.push(key) > limit)
+        delete cache[keylist.shift()];
+      return result;
+    };
+
+  default:
+    return function() {
+      var key = JSON.stringify(arguments);
+      if (key in cache)
+        return cache[key];
+
+      var result = func.apply(null, arguments);
+      cache[key] = result;
+      if (keylist.push(key) > limit)
+        delete cache[keylist.shift()];
+      return result;
+    };
+  }
+}