@stdlib/array/base/arraylike2object/README.md

Arrays.

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# arraylike2object

> Convert an array-like object to an object likely to have the same "shape".

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## Usage

```javascript
var arraylike2object = require( '@stdlib/array/base/arraylike2object' );
```

#### arraylike2object( x )

Converts an array-like object to an object likely to have the same "shape".

```javascript
var obj = arraylike2object( [ 1, 2, 3, 4 ] );
// returns {...}
```

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## Notes

-   The returned object has the following properties:

    -   **data**: reference to the input array.
    -   **dtype**: input array data type. If unable to resolve the [data type][@stdlib/array/dtype] of the input array, the property value is `null`.
    -   **accessorProtocol**: `boolean` indicating whether the input uses accessors for getting and setting elements.
    -   **accessors**: a two-element array whose first element is an accessor for retrieving an array element (i.e., a getter) and whose second element is an accessor for setting an array element (i.e., a setter).

-   The getter accessor accepts two arguments:

    -   **data**: input array.
    -   **idx**: element index.

-   The setter accessor accepts three arguments:

    -   **data**: input array.
    -   **idx**: element index.
    -   **value**: value to set.

-   This function is intended as a potential performance optimization. In V8, for example, even if two objects share common properties, if those properties were added in different orders or if one object has additional properties not shared by the other object, then those objects will have different "hidden" classes. If a function is provided many objects having different "shapes", some JavaScript VMs (e.g., V8) will consider the function "megamorphic" and fail to perform various runtime optimizations. Accordingly, the intent of this function is to standardize the "shape" of the object holding array meta data to ensure that internal functions operating on arrays are provided consistent argument "shapes".

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## Examples

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

```javascript
var Complex64Array = require( '@stdlib/array/complex64' );
var arraylike2object = require( '@stdlib/array/base/arraylike2object' );

// Create an array:
var x = new Complex64Array( 10 );

// Convert to a standardized object:
var obj = arraylike2object( x );
// returns {...}

console.log( obj );
```

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[@stdlib/array/dtype]: https://github.com/stdlib-js/array/tree/main/dtype

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