npm package: @stdlib/iter-none
Description: Test whether all iterated values are falsy.
Author: The Stdlib Authors
Latest version: 0.2.3

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  <summary>
    About stdlib...
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# iterNone

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

> Test whether all [iterated][mdn-iterator-protocol] values are falsy.

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<section class="intro">

</section>

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<section class="installation">

## Installation

```bash
npm install @stdlib/iter-none
```

</section>

<section class="usage">

## Usage

```javascript
var iterNone = require( '@stdlib/iter-none' );
```

#### iterNone( iterator )

Tests whether all [iterated][mdn-iterator-protocol] values are falsy.

```javascript
var array2iterator = require( '@stdlib/array-to-iterator' );

var arr = array2iterator( [ 0, 0, 0, 0, 1 ] );

var bool = iterNone( arr );
// returns false
```

If a provided [`iterator`][mdn-iterator-protocol] does not return any iterated values, the function returns `true`.

```javascript
var array2iterator = require( '@stdlib/array-to-iterator' );

var bool = iterNone( array2iterator( [] ) );
// returns true
```

</section>

<!-- /.usage -->

<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

</section>

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<section class="examples">

## Examples

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

```javascript
var randu = require( '@stdlib/random-iter-randu' );
var iterMap = require( '@stdlib/iter-map' );
var iterNone = require( '@stdlib/iter-none' );

function threshold( r ) {
    return ( r > 0.95 );
}

// Create an iterator which generates uniformly distributed pseudorandom numbers:
var opts = {
    'iter': 100
};
var riter = randu( opts );

// Create an iterator which applies a threshold to generated numbers:
var miter = iterMap( riter, threshold );

// Determine if all values are "falsy":
var bool = iterNone( miter );
// returns <boolean>

console.log( bool );
```

</section>

<!-- /.examples -->

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<section class="references">

</section>

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<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/iter-any`][@stdlib/iter/any]</span><span class="delimiter">: </span><span class="description">test whether at least one iterated value is truthy.</span>
-   <span class="package-name">[`@stdlib/iter-every`][@stdlib/iter/every]</span><span class="delimiter">: </span><span class="description">test whether all iterated values are truthy.</span>
-   <span class="package-name">[`@stdlib/iter-for-each`][@stdlib/iter/for-each]</span><span class="delimiter">: </span><span class="description">create an iterator which invokes a function for each iterated value before returning the iterated value.</span>
-   <span class="package-name">[`@stdlib/iter-none-by`][@stdlib/iter/none-by]</span><span class="delimiter">: </span><span class="description">test whether every iterated value fails a test implemented by a predicate function.</span>
-   <span class="package-name">[`@stdlib/iter-some`][@stdlib/iter/some]</span><span class="delimiter">: </span><span class="description">test whether at least `n` iterated values are truthy.</span>

</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>

<!-- /.stdlib -->

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<section class="links">

[npm-image]: http://img.shields.io/npm/v/@stdlib/iter-none.svg
[npm-url]: https://npmjs.org/package/@stdlib/iter-none

[test-image]: https://github.com/stdlib-js/iter-none/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/iter-none/actions/workflows/test.yml?query=branch:v0.2.3

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/iter-none/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/iter-none?branch=main

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[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/iter-none/tree/deno
[deno-readme]: https://github.com/stdlib-js/iter-none/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/iter-none/tree/umd
[umd-readme]: https://github.com/stdlib-js/iter-none/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/iter-none/tree/esm
[esm-readme]: https://github.com/stdlib-js/iter-none/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/iter-none/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/iter-none/main/LICENSE

[mdn-iterator-protocol]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols#The_iterator_protocol

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

[@stdlib/iter/any]: https://www.npmjs.com/package/@stdlib/iter-any

[@stdlib/iter/every]: https://www.npmjs.com/package/@stdlib/iter-every

[@stdlib/iter/for-each]: https://www.npmjs.com/package/@stdlib/iter-for-each

[@stdlib/iter/none-by]: https://www.npmjs.com/package/@stdlib/iter-none-by

[@stdlib/iter/some]: https://www.npmjs.com/package/@stdlib/iter-some

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

</section>

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