Object

Module	ejs
Definition	dynamic class Object
Stability	Evolving.

The Object Class is the root class from which all objects are based.

It provides a foundation set of functions and properties which are available to all objects. It provides for: copying objects, evaluating equality of objects, providing information about base classes, serialization and deserialization and iteration.

Properties

Qualifiers	Property	Type	Description
get	constructor	Function	The constructor function from which this object was created.
static get set	prototype	Object	The prototype object for objects of this type. The prototype object provides the template for instance properties shared by all objects of a given type.

Object Class Methods

Qualifiers	Method
static	create(prototype: Object, properties: Object = undefined): Object
	Create a new object, set the object prototype and properties.
static	defineProperties(obj: Object, properties: Object): Void
	Define a set of properties on the given object.
static	defineProperty(obj: Object, name: String, options: Object): Void
	Define or redefine a property on the given object.
static	freeze(obj: Object): Void
	Freeze an object.
static	getBaseType(obj: Type): Type
	Get the base type of a type object.
static	getName(obj: Object): String
	Get the name of the object if it is a function or type.
static	getOwnPropertyCount(obj: Object): Number
	The number of properties in the object including non-enumerable properties.
static	getOwnPropertyDescriptor(obj: Object, prop: String): Object
	Get the prototype property descriptor.
static	getOwnPropertyNames(obj: Object, options = null): Array
	Return an array of all property names including non-enumerable properties.
static	getOwnPrototypeOf(obj: Object): Object
	Get the prototype object.
static	getType(obj: Object): Type
	Get the type for an object.
static	getTypeName(obj: Object): String
	Get the name of the type for an object.
static	isExtensible(obj: Object): Boolean
	Test if an object is extensible.
static	isFrozen(obj: Object): Boolean
	Test if an object is frozen.
static	isPrototype(obj: Object): Boolean
	Test if the object is a prototype object.
static	isSealed(obj: Object): Boolean
	Test if an object is sealed.
static	isType(obj: Object): Boolean
	Test if the object is a type object.
static	keys(obj: Object): Array
	Return an array of enumerable property names.
static	preventExtensions(obj: Object): Object
	Prevent extensions to object.
static	seal(obj: Object): Void
	Seal an object.

Object Instance Methods

Qualifiers	Method
	clone(deep: Boolean = true): Object
	Clone the object.
iterator	get(options: Object = null): Iterator
	Get an iterator for this object to be used by "for (v in obj)".
iterator	getValues(): Iterator
	Get an iterator for this object to be used by "for each (v in obj)".
	hasOwnProperty(name: String): Boolean
	Check if an object has a property.
	isPrototypeOf(obj: Object): Boolean
	Is this object a prototype of the nominated argument object.
	propertyIsEnumerable(property: String): Boolean
	Test if the property is enumerable and visible in for/in traversals.
	toJSON(): String
	Convert an object to an equivalent JSON encoded string.
	toLocaleString(): String
	This function converts an object to a localized string representation.
	toString(): String
	This function converts an object to a string representation.
	valueOf(): String
	Return the value of the object.

Method Detail

clone(deep: Boolean = true): Object

Description: Clone the object.

Parameters

deep: Boolean

If true, do a deep copy where all object references are also copied, and so on, recursively. A shallow clone will do 1 level deep. Deep clones are N-level deep. [default: true]

Specified: ejscript-2.7

static create(prototype: Object, properties: Object = undefined): Object

Description: Create a new object, set the object prototype and properties.

Parameters

prototype: Object	Prototype object.
properties: Object	Properties for the new object. [default: undefined]

Returns: The created object h.

static defineProperties(obj: Object, properties: Object): Void

Description: Define a set of properties on the given object.

Parameters

obj: Object	Object on which to define the property.
properties: Object	Hash of property descriptors X.

static defineProperty(obj: Object, name: String, options: Object): Void

Description: Define or redefine a property on the given object.

Parameters

obj: Object	Object on which to define the property.
name: String	Property name.
options: Object	Property descriptor object. The descriptor has properties for: configurable, enumerable, get, namespace, set, value, and writable.

Options

configurable	If true, make the property configurable. This means it can be deleted and have its properties modified.
enumerable	If true, make the property visible to for/in enumerations.
get	Getter function to return the property value.
namespace	Property namespace qualifier.
set	Setter function to update the property value.
value	Initial property value. Cannot use if a get or set property is defined.
writable	If true, the property value may be updated after the initial definition.

static freeze(obj: Object): Void

Description: Freeze an object. This freezes the object in its current configuration. It makes all properties readonly and thens seals the object preventing any properties from changing their configuration. It is useful as the ultimate lock-down for objects.

Parameters

obj: Object

Object to freeze.

iterator get(options: Object = null): Iterator

Description: Get an iterator for this object to be used by "for (v in obj)".

Parameters

options: Object

Iteration options. Reserved for future use. [default: null]

Returns: An iterator object.

Specified: ejscript-2.7

static getBaseType(obj: Type): Type

Description: Get the base type of a type object.

Returns: A type object.

static getName(obj: Object): String

Description: Get the name of the object if it is a function or type.

Returns: The string name of the function or type.

static getOwnPropertyCount(obj: Object): Number

Description: The number of properties in the object including non-enumerable properties.

static getOwnPropertyDescriptor(obj: Object, prop: String): Object

Description: Get the prototype property descriptor. This returns the property descriptor for the named property in the given object. Property names are interpreted using the set of currently open namespaces.

Parameters

obj: Object	Object to inspect.
prop: String	Property name.

Returns: The a property descriptor object. Return null if the property is not found.

static getOwnPropertyNames(obj: Object, options = null): Array

Description: Return an array of all property names including non-enumerable properties. This returns the bare names and does not include the namespace portions of the names. Use getOwnPropertyDescriptor to access property namespace values.

Parameters

obj: Object	Object to inspect.
options	Property selection options. [default: null]

Options

includeBases	Boolean determining if base class properties will included. Defaults to false.
excludeFunctions	Boolean determining if function properties will included. Defaults to false.

Returns: Array of enumerable property names.

static getOwnPrototypeOf(obj: Object): Object

Description: Get the prototype object.

Parameters

obj: Object

Object to inspect.

Returns: The prototype object for the given object.

static getType(obj: Object): Type

Description: Get the type for an object. If the object is an instance, this is the class type object. If the object is a type, this value is Type.

Returns: A type object.

static getTypeName(obj: Object): String

Description: Get the name of the type for an object. If the object is an instance, this is the name of the class type object. If the object is a type, this value is "Type".

Returns: A type object.

iterator getValues(): Iterator

Description: Get an iterator for this object to be used by "for each (v in obj)".

Returns: An iterator object.

Specified: ejscript-2.7

hasOwnProperty(name: String): Boolean

Description: Check if an object has a property. The property names is interpreted using the set of currently open namespaces.

Parameters

name: String

Name of property to check for.

Returns: True if the object contains the specified property.

static isExtensible(obj: Object): Boolean

Description: Test if an object is extensible.

Returns: True if the extensible trait of the object is true H.

static isFrozen(obj: Object): Boolean

Description: Test if an object is frozen.

Parameters

obj: Object

Object to inspect.

Returns: True if the object is frozen.

static isPrototype(obj: Object): Boolean

Description: Test if the object is a prototype object.

Returns: True if the object is being used as a prototype object.

isPrototypeOf(obj: Object): Boolean

Description: Is this object a prototype of the nominated argument object.

Parameters

obj: Object

Target object to use in test.

Returns: True if this is a prototype of obj. TODO - should be on the prototype chain - Need a prototype ns.

static isSealed(obj: Object): Boolean

Description: Test if an object is sealed.

Parameters

obj: Object

Object to inspect.

Returns: True if the object is sealed.

static isType(obj: Object): Boolean

Description: Test if the object is a type object.

Returns: True if the object is a type object.

static keys(obj: Object): Array

Description: Return an array of enumerable property names.

Parameters

obj: Object

Object to inspect.

Returns: Array of enumerable property names.

static preventExtensions(obj: Object): Object

Description: Prevent extensions to object. Sets the extensible property to false.

Returns: The object argument to permit chaining.

propertyIsEnumerable(property: String): Boolean

Description: Test if the property is enumerable and visible in for/in traversals. The property names is interpreted using the set of currently open namespaces.

Parameters

property: String

Name of property to test.

Returns: True if this is a prototype of obj. TODO - prototype property H.

static seal(obj: Object): Void

Description: Seal an object. This prevents changing the configuration of any property. This includes preventing property deletion, changes to property descriptors or adding new properties to the object.

Parameters

obj: Object

Object to seal.

toJSON(): String

Description: Convert an object to an equivalent JSON encoded string.

Returns: This function returns an object literal string.

toLocaleString(): String

Description: This function converts an object to a localized string representation. For many objects, this simply calls toString. If a class overrides, it may perform customized localization. For example: Date.toLocaleString will use the native O/S routines to encode localized dates.

Returns: A localized string representation of the object. 8.

toString(): String

Description: This function converts an object to a string representation. Types typically override this to provide the best string representation.

Returns: A string representation of the object. For Objects "[object className]" will be returned, where className is set to the name of the class on which the object was based.

valueOf(): String

Description: Return the value of the object.

Returns: This object.