'use strict';/** * Determines whether the specified URL is absolute * * @param {string} url The URL to test * @returns {boolean} True if the specified URL is absolute, otherwise false */module.exports=functionisAbsoluteURL(url){// A URL is considered absolute if it begins with "<scheme>://" or "//" (protocol-relative URL).// RFC 3986 defines scheme name as a sequence of characters beginning with a letter and followed// by any combination of letters, digits, plus, period, or hyphen.return/^([a-z][a-z\d\+\-\.]*:)?\/\//i.test(url);};