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- <pre class="prettyprint lang-js"><span id='Object'>/**
- </span> * @class Object
- *
- * Creates an object wrapper.
- *
- * The Object constructor creates an object wrapper for the given value. If the value is null or
- * undefined, it will create and return an empty object, otherwise, it will return an object of a type
- * that corresponds to the given value.
- *
- * When called in a non-constructor context, Object behaves identically.
- *
- * # Using Object given undefined and null types
- *
- * The following examples store an empty Object object in o:
- * var o = new Object();
- *
- * var o = new Object(undefined);
- *
- * var o = new Object(null);
- *
- * # Using Object to create Boolean objects
- *
- * The following examples store Boolean objects in o:
- *
- * // equivalent to o = new Boolean(true);
- * var o = new Object(true);
- *
- * // equivalent to o = new Boolean(false);
- * var o = new Object(Boolean());
- *
- * <div class="notice">
- * Documentation for this class comes from <a href="https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Object">MDN</a>
- * and is available under <a href="http://creativecommons.org/licenses/by-sa/2.0/">Creative Commons: Attribution-Sharealike license</a>.
- * </div>
- */
- <span id='Object-method-constructor'>/**
- </span> * @method constructor
- * Creates new Object.
- * @param {Object} [value] The value to wrap.
- */
- //Properties
- <span id='Object-property-prototype'>/**
- </span> * @property prototype
- * Allows the addition of properties to all objects of type Object.
- */
- //Methods
- <span id='Object-method-hasOwnProperty'>/**
- </span> * @method hasOwnProperty
- * Returns a boolean indicating whether an object contains the specified property as a direct property
- * of that object and not inherited through the prototype chain.
- *
- * Every object descended from `Object` inherits the `hasOwnProperty` method. This method can be used
- * to determine whether an object has the specified property as a direct property of that object;
- * unlike the `in` operator, this method does not check down the object's prototype chain.
- *
- * The following example determines whether the o object contains a property named prop:
- *
- * o = new Object();
- * o.prop = 'exists';
- *
- * function changeO() {
- * o.newprop = o.prop;
- * delete o.prop;
- * }
- *
- * o.hasOwnProperty('prop'); //returns true
- * changeO();
- * o.hasOwnProperty('prop'); //returns false
- *
- * The following example differentiates between direct properties and properties inherited through the
- * prototype chain:
- *
- * o = new Object();
- * o.prop = 'exists';
- * o.hasOwnProperty('prop'); // returns true
- * o.hasOwnProperty('toString'); // returns false
- * o.hasOwnProperty('hasOwnProperty'); // returns false
- *
- * The following example shows how to iterate over the properties of an object without executing on
- * inherit properties.
- *
- * var buz = {
- * fog: 'stack'
- * };
- *
- * for (var name in buz) {
- * if (buz.hasOwnProperty(name)) {
- * alert("this is fog (" + name + ") for sure. Value: " + buz[name]);
- * }
- * else {
- * alert(name); // toString or something else
- * }
- * }
- *
- * @param {String} prop The name of the property to test.
- * @return {Boolean} Returns true if object contains specified property; else
- * returns false.
- */
- <span id='Object-method-isPrototypeOf'>/**
- </span> * @method isPrototypeOf
- * Returns a boolean indication whether the specified object is in the prototype chain of the object
- * this method is called upon.
- *
- * `isPrototypeOf` allows you to check whether or not an object exists within another object's
- * prototype chain.
- *
- * For example, consider the following prototype chain:
- *
- * function Fee() {
- * // . . .
- * }
- *
- * function Fi() {
- * // . . .
- * }
- * Fi.prototype = new Fee();
- *
- * function Fo() {
- * // . . .
- * }
- * Fo.prototype = new Fi();
- *
- * function Fum() {
- * // . . .
- * }
- * Fum.prototype = new Fo();
- *
- * Later on down the road, if you instantiate `Fum` and need to check if `Fi`'s prototype exists
- * within the `Fum` prototype chain, you could do this:
- *
- * var fum = new Fum();
- * . . .
- *
- * if (Fi.prototype.isPrototypeOf(fum)) {
- * // do something safe
- * }
- *
- * This, along with the `instanceof` operator particularly comes in handy if you have code that can
- * only function when dealing with objects descended from a specific prototype chain, e.g., to
- * guarantee that certain methods or properties will be present on that object.
- *
- * @param {Object} prototype an object to be tested against each link in the prototype chain of the
- * *object* argument
- * @param {Object} object the object whose prototype chain will be searched
- * @return {Boolean} Returns true if object is a prototype and false if not.
- */
- <span id='Object-method-propertyIsEnumerable'>/**
- </span> * @method propertyIsEnumerable
- * Returns a boolean indicating if the internal ECMAScript DontEnum attribute is set.
- *
- * Every object has a `propertyIsEnumerable` method. This method can determine whether the specified
- * property in an object can be enumerated by a `for...in` loop, with the exception of properties
- * inherited through the prototype chain. If the object does not have the specified property, this
- * method returns false.
- *
- * The following example shows the use of `propertyIsEnumerable` on objects and arrays:
- *
- * var o = {};
- * var a = [];
- * o.prop = 'is enumerable';
- * a[0] = 'is enumerable';
- *
- * o.propertyIsEnumerable('prop'); // returns true
- * a.propertyIsEnumerable(0); // returns true
- *
- * The following example demonstrates the enumerability of user-defined versus built-in properties:
- *
- * var a = ['is enumerable'];
- *
- * a.propertyIsEnumerable(0); // returns true
- * a.propertyIsEnumerable('length'); // returns false
- *
- * Math.propertyIsEnumerable('random'); // returns false
- * this.propertyIsEnumerable('Math'); // returns false
- *
- * Direct versus inherited properties
- *
- * var a = [];
- * a.propertyIsEnumerable('constructor'); // returns false
- *
- * function firstConstructor()
- * {
- * this.property = 'is not enumerable';
- * }
- * firstConstructor.prototype.firstMethod = function () {};
- *
- * function secondConstructor()
- * {
- * this.method = function method() { return 'is enumerable'; };
- * }
- *
- * secondConstructor.prototype = new firstConstructor;
- * secondConstructor.prototype.constructor = secondConstructor;
- *
- * var o = new secondConstructor();
- * o.arbitraryProperty = 'is enumerable';
- *
- * o.propertyIsEnumerable('arbitraryProperty'); // returns true
- * o.propertyIsEnumerable('method'); // returns true
- * o.propertyIsEnumerable('property'); // returns false
- *
- * o.property = 'is enumerable';
- *
- * o.propertyIsEnumerable('property'); // returns true
- *
- * // These return false as they are on the prototype which
- * // propertyIsEnumerable does not consider (even though the last two
- * // are iteratable with for-in)
- * o.propertyIsEnumerable('prototype'); // returns false (as of JS 1.8.1/FF3.6)
- * o.propertyIsEnumerable('constructor'); // returns false
- * o.propertyIsEnumerable('firstMethod'); // returns false
- *
- * @param {String} prop The name of the property to test.
- * @return {Boolean} If the object does not have the specified property, this
- * method returns false.
- */
- <span id='Object-method-toLocaleString'>/**
- </span> * @method toLocaleString
- * Returns a string representing the object. This method is meant to be overridden by derived objects
- * for locale-specific purposes.
- *
- * `Object`'s `toLocaleString` returns the result of calling `toString`.
- *
- * This function is provided to give objects a generic `toLocaleString` method, even though not all
- * may use it. Currently, only `Array`, `Number`, and `Date` override `toLocaleString`.
- *
- * @return {String} Object represented as a string.
- */
- <span id='Object-method-toString'>/**
- </span> * @method toString
- * Returns a string representation of the object.
- *
- * Every object has a `toString()` method that is automatically called when the object is to be
- * represented as a text value or when an object is referred to in a manner in which a string is
- * expected. By default, the `toString()` method is inherited by every object descended from `Object`.
- * If this method is not overridden in a custom object, `toString()` returns "[object type]", where
- * `type` is the object type. The following code illustrates this:
- *
- * var o = new Object();
- * o.toString(); // returns [object Object]
- *
- * You can create a function to be called in place of the default `toString()` method. The
- * `toString()` method takes no arguments and should return a string. The `toString()` method you
- * create can be any value you want, but it will be most useful if it carries information about the
- * object.
- *
- * The following code defines the `Dog` object type and creates `theDog`, an object of type `Dog`:
- *
- * function Dog(name,breed,color,sex) {
- * this.name=name;
- * this.breed=breed;
- * this.color=color;
- * this.sex=sex;
- * }
- *
- * theDog = new Dog("Gabby","Lab","chocolate","female");
- *
- * If you call the `toString()` method on this custom object, it returns the default value inherited
- * from `Object`:
- *
- * theDog.toString(); //returns [object Object]
- *
- * The following code creates and assigns `dogToString()` to override the default `toString()` method.
- * This function generates a string containing the name, breed, color, and sex of the object, in the
- * form `"property = value;"`.
- *
- * Dog.prototype.toString = function dogToString() {
- * var ret = "Dog " + this.name + " is a " + this.sex + " " + this.color + " " + this.breed;
- * return ret;
- * }
- *
- * With the preceding code in place, any time theDog is used in a string context, JavaScript
- * automatically calls the `dogToString()` function, which returns the following string:
- *
- * Dog Gabby is a female chocolate Lab
- *
- * `toString()` can be used with every object and allows you to get its class. To use the
- * `Object.prototype.toString()` with every object, you need to call `Function.prototype.call()` or
- * `Function.prototype.apply()` on it, passing the object you want to inspect as the first parameter
- * called `thisArg`.
- *
- * var toString = Object.prototype.toString;
- *
- * toString.call(new Date); // [object Date]
- * toString.call(new String); // [object String]
- * toString.call(Math); // [object Math]
- *
- * @return {String} Object represented as a string.
- */
- <span id='Object-method-valueOf'>/**
- </span> * @method valueOf
- * Returns the primitive value of the specified object.
- *
- * JavaScript calls the `valueOf` method to convert an object to a primitive value. You rarely need to
- * invoke the `valueOf` method yourself; JavaScript automatically invokes it when encountering an
- * object where a primitive value is expected.
- *
- * By default, the `valueOf` method is inherited by every object descended from `Object`. Every built-
- * in core object overrides this method to return an appropriate value. If an object has no primitive
- * value, `valueOf` returns the object itself, which is displayed as:
- *
- * [object Object]
- *
- * You can use `valueOf` within your own code to convert a built-in object into a primitive value.
- * When you create a custom object, you can override `Object.valueOf` to call a custom method instead
- * of the default `Object` method.
- *
- * You can create a function to be called in place of the default `valueOf` method. Your function must
- * take no arguments.
- *
- * Suppose you have an object type `myNumberType` and you want to create a `valueOf` method for it.
- * The following code assigns a user-defined function to the object's valueOf method:
- *
- * myNumberType.prototype.valueOf = new Function(functionText)
- *
- * With the preceding code in place, any time an object of type `myNumberType` is used in a context
- * where it is to be represented as a primitive value, JavaScript automatically calls the function
- * defined in the preceding code.
- *
- * An object's `valueOf` method is usually invoked by JavaScript, but you can invoke it yourself as
- * follows:
- *
- * myNumber.valueOf()
- *
- * Note: Objects in string contexts convert via the `toString` method, which is different from
- * `String` objects converting to string primitives using `valueOf`. All objects have a string
- * conversion, if only `"[object type]"`. But many objects do not convert to number, boolean, or
- * function.
- *
- * @return {Object} Returns value of the object or the object itself.
- */
- //Properties
- <span id='Object-property-constructor'>/**
- </span> * @property constructor
- * Specifies the function that creates an object's prototype.
- *
- * Returns a reference to the Object function that created the instance's prototype. Note that the
- * value of this property is a reference to the function itself, not a string containing the
- * function's name, but it isn't read only (except for primitive Boolean, Number or String values: 1,
- * true, "read-only").
- *
- * All objects inherit a `constructor` property from their `prototype`:
- *
- * o = new Object // or o = {} in JavaScript 1.2
- * o.constructor == Object
- * a = new Array // or a = [] in JavaScript 1.2
- * a.constructor == Array
- * n = new Number(3)
- * n.constructor == Number
- *
- * Even though you cannot construct most HTML objects, you can do comparisons. For example,
- *
- * document.constructor == Document
- * document.form3.constructor == Form
- *
- * The following example creates a prototype, `Tree`, and an object of that type, theTree. The example then displays the `constructor` property for the object `theTree`.
- *
- * function Tree(name) {
- * this.name = name;
- * }
- * theTree = new Tree("Redwood");
- * console.log("theTree.constructor is " + theTree.constructor);
- *
- * This example displays the following output:
- *
- * theTree.constructor is function Tree(name) {
- * this.name = name;
- * }
- *
- * The following example shows how to modify constructor value of generic objects. Only true, 1 and
- * "test" variable constructors will not be changed. This example explains that is not always so safe
- * to believe in constructor function.
- *
- * function Type(){};
- * var types = [
- * new Array, [],
- * new Boolean, true,
- * new Date,
- * new Error,
- * new Function, function(){},
- * Math,
- * new Number, 1,
- * new Object, {},
- * new RegExp, /(?:)/,
- * new String, "test"
- * ];
- * for(var i = 0; i < types.length; i++){
- * types[i].constructor = Type;
- * types[i] = [types[i].constructor, types[i] instanceof Type, types[i].toString()];
- * };
- * alert(types.join("\n"));
- */</pre>
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