array.prototype.insert v1.0.3
Array.prototype.insert
This module adds an 'insert' method to the Array object's prototype, which can be used to insert an element into an array at an index calculated by a sorting criteria.
The method uses a binary lookup algorithm to insert the element at the correct index to maintain the appropriate ordering.
The aim of this is to implement a method that is more performant than the native options for inserting and sorting an array. Performance comparisons can be found here: https://jsperf.com/array-prototype-insert/
The method will mutate the original array.
Installation
Install the package using your favourite package manager.
npm install --save array.prototype.insert
Import the package at the top of entry file of your app or the file you want to use it in.
require('array.prototype.insert');
Usage
Assumptions
It is assumed that the array being worked on is empty, or sorted by some criteria and the callback used for comparison is in keeping with this (otherwise unexpected results may occur).
Syntax
arr.insert(itemToInsert, compareFunction[currentValue, insertValue])
arr
- a sorted or empty array- parameters:
itemToInsert
- the item to be inserted into the arraycompareFunction
- the callback used to compare values and decide where to insert the new valuecurrentValue
- the current value being looked upinsertValue
- the value to be inserted
Note: the compareFunction
will by default check if the currentValue
is less than the insertValue
, which will result in ascending order
Examples
Insert into an array with ascending order
const sortedArray = [2, 4, 6, 8]; sortedArray.insert(1) .insert(2) .insert(3) .insert(9) .insert(7); console.log(sortedArray); // output: [1, 2, 2, 3, 4, 6, 7, 8, 9]
Insert into an array with descending order
const sortedArray = [15, 12, 10, 8]; const evaluator = (currentValue, insertValue) => currentValue > insertValue; sortedArray.insert(16, evaluator) .insert(11, evaluator) .insert(9, evaluator); console.log(sortedArray); // output: [16, 15, 12, 11, 10, 9, 8]