npm package: @stdlib/array-base-accessor
Description: Create a minimal array-like object supporting the accessor protocol from another array-like object.
Author: The Stdlib Authors
Latest version: 0.2.3

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# AccessorArray

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> Create a minimal array-like object supporting the accessor protocol from another array-like object.

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/array-base-accessor
```

</section>

<section class="usage">

## Usage

```javascript
var AccessorArray = require( '@stdlib/array-base-accessor' );
```

<a name="constructor"></a>

#### AccessorArray( arr )

Creates a minimal array-like object supporting the accessor protocol from another array-like object.

```javascript
var arr = new AccessorArray( [ 1, 2, 3 ] );
// returns <AccessorArray>
```

* * *

### Properties

<a name="prop-length"></a>

#### AccessorArray.prototype.length

Number of array elements.

```javascript
var arr = new AccessorArray( [ 1, 2, 3 ] );
// returns <AccessorArray>

var len = arr.length;
// returns 3
```

* * *

### Methods

<a name="method-get"></a>

#### AccessorArray.prototype.get( i )

Returns an array element located at position (index) `i`.

```javascript
var arr = new AccessorArray( [ 1, 2, 3 ] );

// Get the first element:
var v = arr.get( 0 );
// returns 1
```

<a name="method-set"></a>

#### AccessorArray.prototype.set( v\[, i] )

Sets an array element.

```javascript
var arr = new AccessorArray( [ 1, 2, 3 ] );

// Get the first element:
var v = arr.get( 0 );
// returns 1

// Set the first element:
arr.set( 5 );

// Get the first element:
v = arr.get( 0 );
// returns 5
```

By default, the method sets array elements starting at position (index) `i = 0`. To set elements starting elsewhere in the array, provide an index argument `i`.

```javascript
var arr = new AccessorArray( [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ] );

// Get the fifth element:
var v = arr.get( 4 );
// returns 5

// Set the fifth element:
arr.set( 11, 4 );

// Get the fifth element:
v = arr.get( 4 );
// returns 11
```

</section>

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<section class="notes">

</section>

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<!-- Package usage examples. -->

<section class="examples">

* * *

## Examples

<!-- eslint-disable no-restricted-syntax -->

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

```javascript
var AccessorArray = require( '@stdlib/array-base-accessor' );

// Define a class for creating a minimal sparse array-like object...
function SparseArray( len, values ) {
    this.length = len;
    this._data = values;
    return this;
}

SparseArray.prototype.get = function get( i ) {
    var v = this._data[ i ];
    if ( v === void 0 ) {
        return 0;
    }
    return v;
};

SparseArray.prototype.set = function set( v, i ) {
    this._data[ i ] = v;
};

// Define a function for printing the contents of an array and which assumes accessor protocol support:
function printArray( name, x ) {
    var i;
    for ( i = 0; i < x.length; i++ ) {
        console.log( '%s[%d] = %d', name, i, x.get( i ) );
    }
}

// Create a sparse array-like object:
var sparse = new SparseArray( 10, {
    '2': 1,
    '3': 2,
    '8': 3
});

// Create a dense array:
var arr = [ 0, 0, 1, 2, 0, 0, 0, 0, 3, 0 ];

// Convert the dense array to an accessor array to allow for uniform iteration:
var dense = new AccessorArray( arr );

// Print the contents of each array...
printArray( 'sparse', sparse );
printArray( 'dense', dense );
```

</section>

<!-- /.examples -->

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* * *

## 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].

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