Description: include options module
 this module has been split out of node-ws, and is
 really only used by node-ws. It has the same upstream as node-ws.
Origin: https://raw2.github.com/einaros/options.js/26806b42/lib/options.js
Last-Update: 2014-01-09
--- /dev/null
+++ b/node_modules/options/index.js
@@ -0,0 +1,86 @@
+/*!
+ * Copyright(c) 2011 Einar Otto Stangvik <einaros@gmail.com>
+ * MIT Licensed
+ */
+ 
+var fs = require('fs');
+
+function Options(defaults) {
+  var internalValues = {};
+  var values = this.value = {};
+  Object.keys(defaults).forEach(function(key) {
+    internalValues[key] = defaults[key];
+    Object.defineProperty(values, key, {
+      get: function() { return internalValues[key]; },
+      configurable: false,
+      enumerable: true
+    });
+  });
+  this.reset = function() {
+    Object.keys(defaults).forEach(function(key) {
+      internalValues[key] = defaults[key];
+    });
+    return this;
+  };
+  this.merge = function(options, required) {
+    options = options || {};
+    if (Object.prototype.toString.call(required) === '[object Array]') {
+      var missing = [];
+      for (var i = 0, l = required.length; i < l; ++i) {
+        var key = required[i];
+        if (!(key in options)) {
+          missing.push(key);
+        }
+      }
+      if (missing.length > 0) {
+        if (missing.length > 1) {
+          throw new Error('options ' +
+            missing.slice(0, missing.length - 1).join(', ') + ' and ' +
+            missing[missing.length - 1] + ' must be defined');
+        }
+        else throw new Error('option ' + missing[0] + ' must be defined');
+      }
+    }
+    Object.keys(options).forEach(function(key) {
+      if (key in internalValues) {
+        internalValues[key] = options[key];
+      }
+    });
+    return this;
+  };
+  this.copy = function(keys) {
+    var obj = {};
+    Object.keys(defaults).forEach(function(key) {
+      if (keys.indexOf(key) !== -1) {
+        obj[key] = values[key];
+      }
+    });
+    return obj;
+  };
+  this.read = function(filename, cb) {
+    if (typeof cb == 'function') {
+      var self = this;
+      fs.readFile(filename, function(error, data) {
+        if (error) return cb(error);
+        var conf = JSON.parse(data);
+        self.merge(conf);
+        cb();
+      });
+    }
+    else {
+      var conf = JSON.parse(fs.readFileSync(filename));
+      this.merge(conf);
+    }
+    return this;
+  };
+  this.isDefined = function(key) {
+    return typeof values[key] != 'undefined';
+  };
+  this.isDefinedAndNonNull = function(key) {
+    return typeof values[key] != 'undefined' && values[key] !== null;
+  };
+  Object.freeze(values);
+  Object.freeze(this);
+}
+
+module.exports = Options;
