mod-loop

JavaScript's modulo operator (%) doesn't handle negative numbers nicely - here's something general to work around the issue.

Benchmarks on jsperf can be found here. Thanks to shama and mikolalysenko for finding a faster method.

Installation

npm install mod-loop

Usage

require('mod-loop')(x, y)

Returns x % y, for both positive and negative and negative numbers.

var mod = require('mod-loop')
 
mod(+100, 10) // 0
mod(-100, 10) // 0
mod(-105, 10) // 5
mod(-102, 10) // 8