102 lines
1.9 KiB
Markdown
102 lines
1.9 KiB
Markdown
<!--
|
|
|
|
@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.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
|
|
-->
|
|
|
|
# Object Keys
|
|
|
|
> Return an array of an object's own and inherited enumerable property names.
|
|
|
|
<section class="usage">
|
|
|
|
## Usage
|
|
|
|
```javascript
|
|
var keysIn = require( '@stdlib/utils/keys-in' );
|
|
```
|
|
|
|
#### keysIn( obj )
|
|
|
|
Returns an `array` of an object's own and inherited enumerable property names.
|
|
|
|
```javascript
|
|
function Foo() {
|
|
this.a = 1;
|
|
return this;
|
|
}
|
|
|
|
Foo.prototype.b = 2;
|
|
|
|
var obj = new Foo();
|
|
|
|
var keys = keysIn( 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.
|
|
|
|
</section>
|
|
|
|
<!-- /.notes -->
|
|
|
|
<section class="examples">
|
|
|
|
## Examples
|
|
|
|
<!-- eslint no-undef: "error" -->
|
|
|
|
```javascript
|
|
var keysIn = require( '@stdlib/utils/keys-in' );
|
|
|
|
function Foo() {
|
|
this.beep = 'boop';
|
|
this.a = {
|
|
'b': 'c'
|
|
};
|
|
return this;
|
|
}
|
|
|
|
Foo.prototype.foo = [ 'bar' ];
|
|
|
|
var obj = new Foo();
|
|
var keys = keysIn( obj );
|
|
|
|
console.log( keys );
|
|
// e.g., => [ 'beep', 'a', 'foo' ]
|
|
```
|
|
|
|
</section>
|
|
|
|
<!-- /.examples -->
|
|
|
|
<section class="links">
|
|
|
|
[ecma-262-for-in]: http://www.ecma-international.org/ecma-262/5.1/#sec-12.6.4
|
|
|
|
</section>
|
|
|
|
<!-- /.links -->
|