@stdlib/utils/any-own-by/README.md

Standard utilities.

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# anyOwnBy

> Test whether at least one own property of a provided object passes a test implemented by a predicate function.

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## Usage

```javascript
var anyOwnBy = require( '@stdlib/utils/any-own-by' );
```

#### anyBy( collection, predicate\[, thisArg ] )

Tests whether at least one own property of a provided [`object`][mdn-object] passes a test implemented by a `predicate` function.

```javascript
function isNegative( value ) {
    return ( value < 0 );
}

var obj = {
    'a': 1,
    'b': 2,
    'c': 3,
    'd': -24,
    'e': 12
};

var bool = anyOwnBy( obj, isNegative );
// returns true
```

If a `predicate` function returns a truthy value, the function **immediately** returns `true`.

```javascript
function isPositive( value ) {
    if ( value < 0 ) {
        throw new Error( 'should never reach this line' );
    }
    return ( value > 0 );
}

var obj = {
    'a': 1,
    'b': 2,
    'c': 3,
    'd': -24,
    'e': 12
};

var bool = anyOwnBy( obj, isPositive );
// returns true
```

The invoked `function` is provided three arguments:

-   **value**: property value.
-   **key**: property key.
-   **obj**: input object.

To set the function execution context, provide a `thisArg`.

```javascript
function verify( value ) {
    this.sum += value;
    this.count += 1;
    return ( value > 0 );
}

var obj = {
    'a': -1,
    'b': -2,
    'c': 3,
    'd': -14
};

var context = {
    'sum': 0,
    'count': 0
};

var bool = anyOwnBy( obj, verify, context );
// returns true

var mean = context.sum / context.count;
// returns 0
```

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## Notes

-   If provided an empty object, the function returns `false`.

    ```javascript
    function verify() {
        return true;
    }
    var bool = anyOwnBy( {}, verify );
    // returns false
    ```

</section>

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## Examples

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

```javascript
var randu = require( '@stdlib/random/base/randu' );
var anyOwnBy = require( '@stdlib/utils/any-own-by' );

function threshold( value ) {
    return ( value > 0.94 );
}

var bool;
var obj = {};
var keys = [ 'a', 'b', 'c', 'd', 'e' ];
var i;
for ( i = 0; i < keys.length; i++ ) {
    obj[ keys[ i ] ] = randu();
}

bool = anyOwnBy( obj, threshold );
// returns <boolean>
```

</section>

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* * *

## See Also

-   <span class="package-name">[`@stdlib/utils/any-by`][@stdlib/utils/any-by]</span><span class="delimiter">: </span><span class="description">test whether at least one element in a collection passes a test implemented by a predicate function.</span>
-   <span class="package-name">[`@stdlib/utils/any-in-by`][@stdlib/utils/any-in-by]</span><span class="delimiter">: </span><span class="description">test whether at least one property in an object passes a test implemented by a predicate function.</span>
-   <span class="package-name">[`@stdlib/utils/every-own-by`][@stdlib/utils/every-own-by]</span><span class="delimiter">: </span><span class="description">test whether all own properties of an object pass a test implemented by a predicate function.</span>
-   <span class="package-name">[`@stdlib/utils/some-own-by`][@stdlib/utils/some-own-by]</span><span class="delimiter">: </span><span class="description">test whether some `own` properties of a provided object satisfy a predicate function for at least `n` properties.</span>

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[mdn-object]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object

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

[@stdlib/utils/any-in-by]: https://github.com/stdlib-js/utils/tree/main/any-in-by

[@stdlib/utils/every-own-by]: https://github.com/stdlib-js/utils/tree/main/every-own-by

[@stdlib/utils/some-own-by]: https://github.com/stdlib-js/utils/tree/main/some-own-by

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</section>

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