outward-search

Search an array of items outwards from a starting index


Keywords
search, array, find, binary search, algorithm, binary-search
License
MIT
Install
npm install outward-search@1.0.3

Documentation

outward-search

Search an array of items outwards from a starting index

Install

yarn add outward-search

Usage

import outwardSearch from 'outward-search';

let arr = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h'];

let match = searchOutwards(arr, 3, (item, index) => {
  console.log('called: ' + item);
  return item === 'e';
});

// called: d
// called: e
// called: c
// called: f
console.log(match); // 'f'

If you need to find an item in an array that you know should be near another item, you can use outward-search to do so efficiently.

export default function outwardSearch<T>(
  items: Array<T>,
  start: number,
  callback: (item: T, index: number) => boolean,
): T | null;

The callback is called on the start index then it works its way outwards to either end of the array.

So with the starting index of 2 and an array with 8 items:

2 // start
3 // up
1 // down
4 // up
0 // down (hit min)
5 // up
6 // up
7 // up (hit max)