writablePropertyNamesIn

Return an array of an object's own and inherited writable property names.

Installation

npm install @stdlib/utils-writable-property-names-in

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.
• If you are using Deno, visit the deno branch.
• For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch.

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

Usage

var writablePropertyNamesIn = require( '@stdlib/utils-writable-property-names-in' );

writablePropertyNamesIn( obj )

Returns an array of an object's own and inherited writable property names.

var defineProperty = require( '@stdlib/utils-define-property' );

var obj = {
    'a': 'b'
};

defineProperty( obj, 'c', {
    'configurable': true,
    'enumerable': true,
    'writable': false,
    'value': 'd'
});

var keys = writablePropertyNamesIn( obj );
// e.g., returns [ 'a', ... ]

Notes

• Name order is not guaranteed, as object key enumeration is not specified according to the ECMAScript specification. In practice, however, most engines use insertion order to sort an object's keys, thus allowing for deterministic extraction.

Examples

var defineProperty = require( '@stdlib/utils-define-property' );
var writablePropertyNamesIn = require( '@stdlib/utils-writable-property-names-in' );

function Foo() {
    this.a = {
        'b': 'c'
    };
    defineProperty( this, 'baz', {
        'configurable': true,
        'enumerable': true,
        'writable': false,
        'value': 'qux'
    });
    return this;
}

Foo.prototype.foo = [ 'bar' ];
defineProperty( Foo.prototype, 'bip', {
    'configurable': true,
    'enumerable': true,
    'writable': false,
    'value': 'bop'
});

var obj = new Foo();
var keys = writablePropertyNamesIn( obj );

console.log( keys );
// e.g., => [ 'a', 'foo', ... ]

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See Also

• @stdlib/utils-inherited-writable-property-names: return an array of an object's inherited writable property names.
• @stdlib/utils-writable-properties-in: return an array of an object's own and inherited writable property names and symbols.
• @stdlib/utils-writable-property-names: return an array of an object's own writable property names.
• @stdlib/utils-writable-property-symbols-in: return an array of an object's own and inherited writable symbol properties.
• @stdlib/utils-property-names-in: return an array of an object's own and inherited enumerable and non-enumerable property names.

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Notice

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.

Community

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License

See LICENSE.

Copyright

Copyright © 2016-2023. The Stdlib Authors.