@stdlib/assert-is-writable-property-in NPM

isWritablePropertyIn

Test if an object's own or inherited property is writable.

Installation

npm install @stdlib/assert-is-writable-property-in

Usage

var isWritablePropertyIn = require( '@stdlib/assert-is-writable-property-in' );

isWritablePropertyIn( value, property )

Returns a boolean indicating if a value has a writable property.

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

var obj = {
    'foo': 'bar'
};

defineProperty( obj, 'beep', {
    'configurable': false,
    'enumerable': false,
    'writable': false,
    'value': 'boop'
});

defineProperty( obj, 'setter', {
    'configurable': false,
    'enumerable': false,
    'set': function setter( v ) {
        obj.foo = v;
    }
});

var bool = isWritablePropertyIn( obj, 'foo' );
// returns true

bool = isWritablePropertyIn( obj, 'setter' );
// returns true

bool = isWritablePropertyIn( obj, 'beep' );
// returns false

Notes

Value arguments other than null or undefined are coerced to objects.

var bool = isWritablePropertyIn( 'beep', 'toString' );
// returns true

Property arguments are coerced to strings.

var obj = {
    'null': 'foo'
};

var bool = isWritablePropertyIn( obj, null );
// returns true

Examples

var isWritablePropertyIn = require( '@stdlib/assert-is-writable-property-in' );

var bool = isWritablePropertyIn( [ 'a' ], 'length' );
// returns true

bool = isWritablePropertyIn( { 'a': 'b' }, 'a' );
// returns true

bool = isWritablePropertyIn( [ 'a' ], 0 );
// returns true

bool = isWritablePropertyIn( { 'null': false }, null );
// returns true

bool = isWritablePropertyIn( { '[object Object]': false }, {} );
// returns true

bool = isWritablePropertyIn( {}, 'toString' );
// returns true

bool = isWritablePropertyIn( {}, 'hasOwnProperty' );
// returns true

bool = isWritablePropertyIn( null, 'a' );
// returns false

bool = isWritablePropertyIn( void 0, 'a' );
// returns false

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.