if (!String.prototype.padStart) { String.prototype.padStart = function padStart(targetLength, padString) { targetLength = targetLength >> 0; padString = String(typeof padString !== 'undefined' ? padString : ' '); if (this.length > targetLength) { return String(this); } else { targetLength = targetLength - this.length; if (targetLength > padString.length) { padString += padString.repeat(targetLength / padString.length); //append to original to ensure we are longer than needed } return padString.slice(0, targetLength) + String(this); } }; }