# .has()

### has(filter)

| **Parameter** | **Description**                                                                                                                                                                                                                                              |
| ------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| filter        | <p><a href="https://developer.mozilla.org/en-US/docs/Glossary/Callback_function">Callback</a></p><p>Function to test each element of the array. Return a value that coerces to <code>true</code> to keep the element, or to <code>false</code> otherwise</p> |

| **Returns**                                                                                         | **Description**                                                |
| --------------------------------------------------------------------------------------------------- | -------------------------------------------------------------- |
| [Boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean) | Whether or not there is any entry matching the provided filter |

```javascript
// Note: Users is a collection.

Users.get(); // [{ id: 1, name: '5antos' }]

Users.has(u => u.name === '5antos'); // true
Users.has(u => u.id === 2); // false
```


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