time-to-botec/js/node_modules/@stdlib/utils/property-names/README.md

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@license Apache-2.0
Copyright (c) 2018 The Stdlib Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
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# propertyNames
> Return an array of an object's own enumerable and non-enumerable property names.
<section class="usage">
## Usage
```javascript
var propertyNames = require( '@stdlib/utils/property-names' );
```
#### propertyNames( obj )
Returns an `array` of an object's own enumerable and non-enumerable property names.
```javascript
var obj = {
'a': 1,
'b': 2
};
var keys = propertyNames( obj );
// e.g., returns [ 'a', 'b' ]
```
</section>
<!-- /.usage -->
<section class="notes">
## Notes
- Name order is not guaranteed, as `object` key enumeration is not specified according to the [ECMAScript specification][ecma-262-for-in]. In practice, however, most engines use insertion order to sort an `object`'s keys, thus allowing for deterministic extraction.
- In contrast to the built-in `Object.getOwnPropertyNames()`, if provided `null` or `undefined`, the function returns an empty `array`, rather than throwing an error.
</section>
<!-- /.notes -->
<section class="examples">
## Examples
<!-- eslint no-undef: "error" -->
```javascript
var defineProperty = require( '@stdlib/utils/define-property' );
var propertyNames = require( '@stdlib/utils/property-names' );
function Foo() {
this.beep = 'boop';
this.a = {
'b': 'c'
};
defineProperty( this, 'baz', {
'value': 'qux',
'configurable': true,
'writable': true,
'enumerable': false
});
return this;
}
Foo.prototype.foo = [ 'bar' ];
var obj = new Foo();
var keys = propertyNames( obj );
console.log( keys );
// e.g., => [ 'beep', 'a', 'baz' ]
```
</section>
<!-- /.examples -->
<section class="links">
[ecma-262-for-in]: http://www.ecma-international.org/ecma-262/5.1/#sec-12.6.4
</section>
<!-- /.links -->