@pelevesque/find-duplicates

find-duplicates

Finds indices of duplicates in an array of elements.

find-duplicates uses lodash.isequal to make comparisons, so any type supported by lodash.isequal is supported by find-duplicates.

Node Repository

https://www.npmjs.com/package/@pelevesque/find-duplicates

Installation

npm install @pelevesque/find-duplicates

Tests

Standard Style & Unit Tests

npm test

Unit Tests & Coverage

npm run cover

Usage

Requiring the Module

const findDuplicates = require('@pelevesque/find-duplicates')

One Set of Duplicates

const elements = [
  'd131dd02c5e6eec4', // a
  '55ad340609f4b302',
  'd131dd02c5e6eec4', // a
  'd131dd02c5e6eec4', // a
  'd8823e3156348f5b'
]
const result = findDuplicates(elements)
// result === [[0, 2, 3]]

Many Sets of Duplicates

const elements = [
  'd131dd02c5e6eec4', // a
  '55ad340609f4b302',
  'd8823e3156348f5b', // b
  'd131dd02c5e6eec4', // a
  'd8823e3156348f5b', // b
  '551111111114b302', // c
  '551111111114b302'  // c
]
const result = findDuplicates(elements)
// result === [[0, 3], [2, 4], [5, 6]]

Using the stopAtFirstSet Flag

// When using the stopAtFirstSet flag, only the first set is returned.
// Note: In this case, an array is returned instead of an array of arrays.
const elements = [
  'd131dd02c5e6eec4', // a
  '55ad340609f4b302',
  'd8823e3156348f5b', // b
  'd131dd02c5e6eec4', // a
  'd8823e3156348f5b', // b
  '551111111114b302', // c
  '551111111114b302'  // c
]
const stopAtFirstSet = true
const result = findDuplicates(elements, stopAtFirstSet)
// result === [0, 3]