nonEnumerablePropertyNames

Return an array of an object's own non-enumerable property names.

Usage

var nonEnumerablePropertyNames = require( '@stdlib/utils/nonenumerable-property-names' );

nonEnumerablePropertyNames( obj )

Returns an array of an object's own non-enumerable property names.

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

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

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

var keys = nonEnumerablePropertyNames( obj );
// returns [ 'c' ]

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 nonEnumerablePropertyNames = require( '@stdlib/utils/nonenumerable-property-names' );

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

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

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

console.log( keys );
// => [ 'baz' ]
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