Test if a value is a collection.
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> Test if a value is a collection.
A collection is defined as either an [Array][mdn-array], [Typed Array][mdn-typed-array], or an array-like [Object][mdn-object] (excluding strings and functions).
``bash`
npm install @stdlib/assert-is-collection
`javascript`
var isCollection = require( '@stdlib/assert-is-collection' );
#### isCollection( value )
Tests if a value is a collection.
`javascript`
var bool = isCollection( [] );
// returns true
`javascript
var Int8Array = require( '@stdlib/array-int8' );
var Uint8Array = require( '@stdlib/array-uint8' );
var Uint8ClampedArray = require( '@stdlib/array-uint8c' );
var Int16Array = require( '@stdlib/array-int16' );
var Uint16Array = require( '@stdlib/array-uint16' );
var Int32Array = require( '@stdlib/array-int32' );
var Uint32Array = require( '@stdlib/array-uint32' );
var Float32Array = require( '@stdlib/array-float32' );
var Float64Array = require( '@stdlib/array-float64' );
var isCollection = require( '@stdlib/assert-is-collection' );
var bool = isCollection( [] );
// returns true
bool = isCollection( new Float64Array( 10 ) );
// returns true
bool = isCollection( new Float32Array( 10 ) );
// returns true
bool = isCollection( new Int32Array( 10 ) );
// returns true
bool = isCollection( new Uint32Array( 10 ) );
// returns true
bool = isCollection( new Int16Array( 10 ) );
// returns true
bool = isCollection( new Uint16Array( 10 ) );
// returns true
bool = isCollection( new Int8Array( 10 ) );
// returns true
bool = isCollection( new Uint8Array( 10 ) );
// returns true
bool = isCollection( new Uint8ClampedArray( 10 ) );
// returns true
bool = isCollection( { 'length': 0 } );
// returns true
bool = isCollection( {} );
// returns false
bool = isCollection( 'beep' );
// returns false
bool = isCollection( isCollection );
// returns false
bool = isCollection( null );
// returns false
bool = isCollection( void 0 );
// returns false
bool = isCollection( 3.14 );
// returns false
`
*
- [@stdlib/assert-is-array-like][@stdlib/assert/is-array-like]: test if a value is array-like.
- [@stdlib/assert-is-array-like-object][@stdlib/assert/is-array-like-object]: test if a value is an array-like object.
*
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].
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
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[npm-url]: https://npmjs.org/package/@stdlib/assert-is-collection
[test-image]: https://github.com/stdlib-js/assert-is-collection/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/assert-is-collection/actions/workflows/test.yml?query=branch:v0.2.3
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[coverage-url]: https://codecov.io/github/stdlib-js/assert-is-collection?branch=main
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[chat-url]: https://stdlib.zulipchat.com
[stdlib]: https://github.com/stdlib-js/stdlib
[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors
[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/assert-is-collection/tree/deno
[deno-readme]: https://github.com/stdlib-js/assert-is-collection/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/assert-is-collection/tree/umd
[umd-readme]: https://github.com/stdlib-js/assert-is-collection/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/assert-is-collection/tree/esm
[esm-readme]: https://github.com/stdlib-js/assert-is-collection/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/assert-is-collection/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-is-collection/main/LICENSE
[mdn-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array
[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray
[mdn-object]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object
[@stdlib/assert/is-array-like]: https://www.npmjs.com/package/@stdlib/assert-is-array-like
[@stdlib/assert/is-array-like-object]: https://www.npmjs.com/package/@stdlib/assert-is-array-like-object