https://github.com/xotic750/find-index-x

Return the index of the first element in the array that satisfies the provided testing function.
https://github.com/xotic750/find-index-x

array browser ecmascript findindex nodejs

Last synced: 2 months ago
JSON representation

Return the index of the first element in the array that satisfies the provided testing function.

• Host: GitHub
• URL: https://github.com/xotic750/find-index-x
• Owner: Xotic750
• License: mit
• Created: 2017-03-30T08:21:21.000Z (almost 8 years ago)
• Default Branch: master
• Last Pushed: 2023-01-04T21:54:50.000Z (about 2 years ago)
• Last Synced: 2024-11-11T20:48:03.345Z (2 months ago)
• Topics: array, browser, ecmascript, findindex, nodejs
• Language: JavaScript
• Homepage:
• Size: 3.44 MB
• Stars: 0
• Watchers: 2
• Forks: 0
• Open Issues: 21
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

        












































## find-index-x

This method returns the index of the first element in the array that satisfies the provided testing function.



### `module.exports` ⇒ number ⏏

Like `findIndex`, this method returns an index in the array, if an element

in the array satisfies the provided testing function. Otherwise -1 is returned.

**Kind**: Exported member  

**Returns**: number - Returns index of positively tested element, otherwise -1.  

**Throws**:

- TypeError If array is `null` or `undefined`-

- TypeError If `callback` is not a function.

| Param     | Type                  | Description                                                                                             |

| --------- | --------------------- | ------------------------------------------------------------------------------------------------------- |

| array     | Array    | The array to search.                                                                                    |

| callback  | function | Function to execute on each value in the array, taking three arguments: `element`, `index` and `array`. |

| [thisArg] | \*       | Object to use as `this` when executing `callback`.                                                      |

**Example**

```js

import findIndex from 'find-index-x';

function isPrime(element, index, array) {

  let start = 2;

  while (start <= Math.sqrt(element)) {

    if (element % start < 1) {

      return false;

    }

    start += 1;

  }

  return element > 1;

}

console.log(findIndex([4, 6, 8, 12, 14], isPrime)); // -1, not found

console.log(findIndex([4, 6, 7, 12, 13], isPrime)); // 2

```