is-array-of-length

Returns true if a value is an array containing the specified number of elements.

Installation

Requires Node.js 6.0.0 or above.

npm i is-array-of-length

API

The module exports a single function.

Parameters

1. arr (any): What may or may not be an array
2. lengths (integer or array): One or more integers, each of which represents an acceptable number of items in the array.
3. Optional: Object argument:
   • arrays (class, string, or array): One or more classes or names of classes that should be treated as equivalent to Array.

Return Values

• true if arr is an array with a length given in lengths
• false otherwise

Example

const isArrayOfLength = require('is-array-of-length')

isArrayOfLength(['a', 'b'], 2) // true
isArrayOfLength(['a', 'b'], 3) // false
isArrayOfLength(['a', 'b'], [2, 3]) // true
isArrayOfLength('7 chars', 7) // false

// Supports the bind operator
['a', 'b']::isArrayOfLength(2) // true