index.js

'use strict';
const ipRegex = require('ip-regex');

const isIp = string => ipRegex({exact: true}).test(string);
isIp.v4 = string => ipRegex.v4({exact: true}).test(string);
isIp.v6 = string => ipRegex.v6({exact: true}).test(string);
isIp.version = string => isIp(string) ? (isIp.v4(string) ? 4 : 6) : undefined;

module.exports = isIp;