@stdlib/iter/cusome/README.md

Standard iterator utilities.

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# iterCuSome

> Create an iterator which cumulatively tests whether at least `n` iterated values are truthy.

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## Usage

```javascript
var iterCuSome = require( '@stdlib/iter/cusome' );
```

#### iterCuSome( iterator, n )

Returns an [iterator][mdn-iterator-protocol] which cumulatively tests whether at least `n` iterated values are truthy.

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

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

var it = iterCuSome( arr, 2 );

var v = it.next().value;
// returns false

v = it.next().value;
// returns false

v = it.next().value;
// returns false

v = it.next().value;
// returns true

v = it.next().value;
// returns true

var bool = it.next().done;
// returns true
```

The returned [iterator][mdn-iterator-protocol] protocol-compliant object has the following properties:

-   **next**: function which returns an [iterator][mdn-iterator-protocol] protocol-compliant object containing the next iterated value (if one exists) assigned to a `value` property and a `done` property having a `boolean` value indicating whether the [iterator][mdn-iterator-protocol] is finished.
-   **return**: function which closes an [iterator][mdn-iterator-protocol] and returns a single (optional) argument in an [iterator][mdn-iterator-protocol] protocol-compliant object.

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## Examples

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

```javascript
var randu = require( '@stdlib/random/iter/randu' );
var iterMap = require( '@stdlib/iter/map' );
var iterCuSome = require( '@stdlib/iter/cusome' );

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 );

// Create an iterator which cumulatively tests whether at least 5 iterated values are truthy:
var it = iterCuSome( miter, 5 );

// Perform manual iteration...
var r;
while ( true ) {
    r = it.next();
    if ( r.done ) {
        break;
    }
    console.log( r.value );
}
```

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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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