array-duplicates

Returns the duplicated items found in an array

Usage no npm install needed!

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README

Array duplicates

Returns the duplicated items in an array.

Install

npm install array-duplicates

Usage

Given an array with duplicates, obtain the duplicated items:

const duplicates = require('array-duplicates')

console.log(duplicates([1, 2, 3, 2, 3, 4])) // [2, 3]
console.log(duplicates([{ id: 1 }, { id: 2 }, { id: 2 }], i => i.id)) // [{ id: 2 }]

API

duplicates(array[, identity])

  • array is an array containing numbers, string and/or objects.
  • identity is an optional function that will recieve each item in the array and shall return a value that represents that item. Is needed when comparing objects, otherwhise, the objects will be compared by reference instead of content.

License

WTFPL