Indian Numbering System Currency Formatter

function formatCurrency(number) {
    var numberStr = number.toString();
    var thousandsMatcher = /(\d+)(\d{3})$/;
    var thousandsAndRest = thousandsMatcher.exec(numberStr);
    if (!thousandsAndRest) return numberStr;
    return thousandsAndRest[1].replace(/\B(?=(\d{2})+(?!\d))/g, ",") + "," + thousandsAndRest[2];
}