npm install @stdlib/object-ctor

Alternatively,

• To load the package in a website via a script tag without installation and bundlers, use the ES Module available on the esm branch (see README).
• If you are using Deno, visit the deno branch (see README for usage intructions).
• For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch (see README).

The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.

To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.

var Object = require( '@stdlib/object-ctor' );

Returns a new object.

var o = new Object( null );
// returns {}

Property whose value is a reference to the constructor function that created the instance object.

var o = new Object( null );
var ctr = o.constructor;
// returns Object

Assigns enumerable properties of one or more source objects to a target object.

var o = Object.assign( {}, { 'a': 1, 'b': 2 } );
// returns { 'a': 1, 'b': 2 }

Returns a new object with the given prototype and properties.

var o = Object.create( null, {
    'a': {
        'value': 1
    },
    'b': {
        'value': 2
    }
});
// returns { 'a': 1, 'b': 2 }

function Person( first, last ) {
    this.first = first;
    this.last = last;
}

var p = Object.create( Person.prototype, {
    'first': {
        'value': 'Jane'
    },
    'last': {
        'value': 'Doe'
    }
});
// returns Person { 'first': 'Jane', 'last': 'Doe' }

Defines new or modifies existing properties directly on an object, returning the object.

var o = Object.defineProperties( {}, {
    'a': {
        'value': 1
    },
    'b': {
        'value': 2
    }
});
// returns { 'a': 1, 'b': 2 }

Defines a new property directly on an object, or modifies an existing property on an object, and returns the object.

var o = Object.defineProperty( {}, 'a', {
    'value': 1,
    'writable': true,
    'enumerable': true,
    'configurable': true
});
// returns { 'a': 1 }

Returns an array of a given object's own enumerable string-keyed property entries, i.e. [key, value] pairs.

var o = { 'a': 1, 'b': 2 };
var arr = Object.entries( o );
// e.g., returns [ [ 'a', 1 ], [ 'b', 2 ] ]

Freezes an object. A frozen object can no longer be changed; freezing an object prevents new properties from being added to it, existing properties from being removed, and existing properties from being changed.

var o = { 'a': 1 };
Object.freeze( o );
// returns { 'a': 1 }

o.b = 1;
var v = o.b;
// returns undefined

Returns an object that contains the properties of the given object.

var o = { 'a': 1 };
var d = Object.getOwnPropertyDescriptor( o, 'a' );
// returns { 'value': 1, 'writable': true, 'enumerable': true, 'configurable': true }

Returns an object whose properties are the result of calling Object.getOwnPropertyDescriptor() on every property of the given object.

var o = { 'a': 1, 'b': 2 };
var d = Object.getOwnPropertyDescriptors( o );
// returns { 'a': { 'value': 1, 'writable': true, 'enumerable': true, 'configurable': true }, 'b': { 'value': 2, 'writable': true, 'enumerable': true, 'configurable': true } }

Returns an array of a given object's own property names.

var o = { 'a': 1, 'b': 2 };
var arr = Object.getOwnPropertyNames( o );
// e.g., returns [ 'a', 'b' ]

Returns an array of a given object's own property symbols.

var o = { 'a': 1 };
o[ Symbol( 'b' ) ] = 2;
var arr = Object.getOwnPropertySymbols( o );
// returns [ Symbol(b) ]

Returns the prototype of an object.

var o = { 'a': 1 };
var p = Object.getPrototypeOf( o );
// returns {}

Returns a boolean indicating whether an object has a property with the specified name.

var o = { 'a': 1 };
var b = Object.hasOwn( o, 'b' );
// returns false

Returns a boolean indicating whether an object has a property with the specified name.

var o = { 'a': 1 };
var b = o.hasOwnProperty( 'a' );
// returns true

Returns a boolean indicating whether two values are the same value.

var b = Object.is( 1, 1 );
// returns true

b = Object.is( 1, '1' );
// returns false

Returns a boolean indicating whether an object is extensible (whether new properties can be added to it).

var o = { 'a': 1 };
var b = Object.isExtensible( o );
// returns true

Object.preventExtensions( o );
b = Object.isExtensible( o );
// returns false

Returns a boolean indicating whether an object is frozen. Frozen objects can no longer be changed; freezing an object prevents new properties from being added to it, existing properties from being removed, and existing properties from being changed.

var o = { 'a': 1 };
var b = Object.isFrozen( o );
// returns false

Object.freeze( o );
b = Object.isFrozen( o );
// returns true

Returns a boolean indicating whether an object is in the prototype chain of another object.

var o = { 'a': 1 };
var p = { '__proto__': o };
var b = o.isPrototypeOf( p );
// returns true

Returns a boolean indicating whether an object is sealed. An object is sealed if it is not extensible and all of its properties are non-configurable.

var o = { 'a': 1 };
var b = Object.isSealed( o );
// returns false

Object.seal( o );
b = Object.isSealed( o );
// returns true

Returns an array of a given object's own enumerable property names.

var o = { 'a': 1, 'b': 2 };
var arr = Object.keys( o );
// e.g., returns [ 'a', 'b' ]

Prevents new properties from being added to an object.

var o = { 'a': 1 };
Object.preventExtensions( o );
o.b = 2;
var b = ( o.b === void 0 );
// returns true

o.a = 3;
b = ( o.a === 3 );
// returns true

Returns a boolean indicating whether a property is enumerable.

var o = { 'a': 1 };
var b = o.propertyIsEnumerable( 'a' );
// returns true

var arr = [ 1, 2, 3 ];
b = arr.propertyIsEnumerable( 'length' );
// returns false

Seals an object, preventing new properties from being added to it (i.e., making it non extensible) and marking all existing properties as non-configurable.

var o = { 'a': 1 };
Object.seal( o );

o.b = 2;
var b = ( o.b === void 0 );
// returns true

Sets the prototype of an object.

var o = { 'a': 1 };
var p = { 'b': 2 };
Object.setPrototypeOf( o, p );

var b = ( o.b === 2 );
// returns true

Returns a string representing the object.

var o = { 'a': 1 };
var str = o.toLocaleString();
// returns <string>

Returns a string representing the object.

var o = { 'a': 1 };
var str = o.toString();
// returns <string>

Returns the primitive value of the object.

var o = {};
var v = o.valueOf();
// returns {}

Returns an array of a given object's own enumerable property values.

var o = { 'a': 1, 'b': 2 };
var arr = Object.values( o );
// e.g., returns [ 1, 2 ]

• If provided null or undefined, the function returns an empty object.
• If provided an existing object, the function returns the input value unchanged.
• Otherwise, if provided any other value (e.g., a number, string, etc), the function will return an object of the corresponding type.

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

See LICENSE.

Copyright © 2016-2024. The Stdlib Authors.