@stdlib/utils/deep-get/README.md

Standard utilities.

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# Deep Get

> Get a nested property value.

<section class="usage">

## Usage

```javascript
var deepGet = require( '@stdlib/utils/deep-get' );
```

#### deepGet( obj, path\[, options] )

Returns a nested property value.

<!-- eslint-disable object-curly-newline, object-curly-spacing -->

```javascript
var obj = { 'a': { 'b': { 'c': 'd' } } };

var val = deepGet( obj, 'a.b.c' );
// returns 'd'
```

For `paths` including `arrays`, specify the numeric index.

<!-- eslint-disable object-curly-newline, object-curly-spacing -->

```javascript
var arr = [
    { 'a': [ {'x': 5} ] },
    { 'a': [ {'x': 10} ] }
];

var val = deepGet( arr, '1.a.0.x' );
// returns 10
```

The key `path` may be specified as either a delimited `string` or a key `array`.

<!-- eslint-disable object-curly-newline, object-curly-spacing -->

```javascript
var obj = { 'a': { 'b': { 'c': 'd' } } };

var val = deepGet( obj, [ 'a', 'b', 'c' ] );
// returns 'd'
```

The function accepts the following `options`:

-   **sep**: key path separator. Default: `'.'`.

By default, the function assumes `dot` separated key values. To specify an alternative separator, set the `sep` option.

<!-- eslint-disable object-curly-newline, object-curly-spacing -->

```javascript
var obj = { 'a': { 'b': { 'c': 'd' } } };

var val = deepGet( obj, 'a/b/c', {
    'sep': '/'
});
// returns 'd'
```

#### deepGet.factory( path\[, options] )

Creates a reusable deep get function. The factory method ensures a `deepGet` function is configured identically by using the same set of provided `options`.

```javascript
var dget = deepGet.factory( 'a/b/c', {
    'sep': '/'
});
```

#### dget( obj )

Returns a nested property value.

<!-- eslint-disable object-curly-newline, object-curly-spacing -->

```javascript
var dget = deepGet.factory( 'a.b.c' );

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

var val = dget( obj );
// returns 'd'
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var randu = require( '@stdlib/random/base/randu' );
var deepGet = require( '@stdlib/utils/deep-get' );

var data;
var keys;
var val;
var i;

data = new Array( 100 );
for ( i = 0; i < data.length; i++ ) {
    data[ i ] = {
        'x': Date.now(),
        'y': [ randu(), randu(), i ]
    };
}

keys = [ 0, 'y', 2 ];
for ( i = 0; i < data.length; i++ ) {
    keys[ 0 ] = i;
    val = deepGet( data, keys );
    console.log( val );
}
```

</section>

<!-- /.examples -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/utils/deep-pluck`][@stdlib/utils/deep-pluck]</span><span class="delimiter">: </span><span class="description">extract a nested property value from each element of an object array.</span>
-   <span class="package-name">[`@stdlib/utils/deep-set`][@stdlib/utils/deep-set]</span><span class="delimiter">: </span><span class="description">set a nested property value.</span>

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

<!-- <related-links> -->

[@stdlib/utils/deep-pluck]: https://github.com/stdlib-js/utils/tree/main/deep-pluck

[@stdlib/utils/deep-set]: https://github.com/stdlib-js/utils/tree/main/deep-set

<!-- </related-links> -->

</section>

<!-- /.links -->