@stdlib/iter/none/README.md

Standard iterator utilities.

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# iterNone

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

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## 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
```

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## 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 );
```

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* * *

## 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>

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

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[@stdlib/iter/any]: https://github.com/stdlib-js/iter/tree/main/any

[@stdlib/iter/every]: https://github.com/stdlib-js/iter/tree/main/every

[@stdlib/iter/for-each]: https://github.com/stdlib-js/iter/tree/main/for-each

[@stdlib/iter/none-by]: https://github.com/stdlib-js/iter/tree/main/none-by

[@stdlib/iter/some]: https://github.com/stdlib-js/iter/tree/main/some

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