npm package: @stdlib/array-base-rekey-views
Description: Create an array containing views with renamed keys for every element in a provided array.
Author: The Stdlib Authors
Latest version: 0.1.1

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# rekeyViews

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> Create an array containing views with renamed keys for every element in a provided array.

<section class="installation">

## Installation

```bash
npm install @stdlib/array-base-rekey-views
```

</section>

<section class="usage">

## Usage

```javascript
var rekeyViews = require( '@stdlib/array-base-rekey-views' );
```

#### rekeyViews( arr, mapping )

Returns an array containing views with renamed keys for every element in a provided array.

```javascript
var x = [
    {
        'x': 1,
        'y': 2
    },
    {
        'x': 3,
        'y': 4
    }
];
var mapping = {
    'x': 'a',
    'y': 'b'
};

var out = rekeyViews( x, mapping );
// returns [ <Object>, <Object> ]

var v0 = out[ 0 ].toJSON();
// returns { 'a': 1, 'b': 2 }

var v1 = out[ 1 ].toJSON();
// returns { 'a': 3, 'b': 4 }

// Mutate the first element in the input array:
x[ 0 ].x = 5;

v0 = out[ 0 ].toJSON();
// returns { 'a': 5, 'b': 2 }

// Set a view property:
out[ 1 ].b = 'beep';

v1 = out[ 1 ].toJSON();
// returns { 'a': 3, 'b': 'beep' }

var y = x.slice();
// returns [ { 'x': 5, 'y': 2 }, { 'x': 3, 'y': 'beep' } ]
```

The function has the following parameters:

-   **arr**: input array.
-   **mapping**: object mapping existing keys to new key names.

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   The function returns views having **only** those keys which are present in a provided mapping object. Any keys which are **not** present in the provided mapping object, but are present in the original objects, are **omitted** during view creation.
-   The function assumes that each object has the keys specified in a provided mapping object.
-   Each view in the returned array shares the same memory as the corresponding elements in the input arrays. Accordingly, mutation of either an array element or a view will mutate the other.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random-base-discrete-uniform' );
var filledBy = require( '@stdlib/array-base-filled-by' );
var rekeyViews = require( '@stdlib/array-base-rekey-views' );

function clbk( idx ) {
    return {
        'x': idx,
        'y': discreteUniform( 0, 10 )
    };
}

var x = filledBy( 10, clbk );
var mapping = {
    'x': 'a',
    'y': 'b'
};

var out = rekeyViews( x, mapping );
// returns [...]
```

</section>

<!-- /.examples -->

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<section class="related">

</section>

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<section class="main-repo" >

* * *

## Notice

This package is part of [stdlib][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][stdlib], see the main project [repository][stdlib].

#### Community

[![Chat][chat-image]][chat-url]

---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

</section>

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[umd]: https://github.com/umdjs/umd
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</section>

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