function isEmpty(s) {
    return (s == null) || (s.length == 0);
}
function isValidEmailAddress(s) {
    var emailRegex = /^[a-zA-Z0-9._%-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/;
    return emailRegex.test(s);
}
function isFloat(s) {
    var seenDecimalPoint = false;
    var k;
    if ((s == null) || (s.length == 0)) {
        return false;
    }
    else if (s == ".") {
        return false;
    }
    for (k = 0; k < s.length; ++k) {
        var c = s.charAt(k);
        if ((c == ".") && !seenDecimalPoint) {
            seenDecimalPoint = true;
        }
        else if ((c < "0") || (c > "9")) {
            return false;
        }
    }
    return true;
}
function isInteger(s) {
    var k;
    if ((s == null) || (s.length == 0)) {
        return false;
    }
    for (k = 0; k < s.length; ++k) {
        var c = s.charAt(k);
        if ((c < "0") || (c > "9")) {
            return false;
        }
    }
    return true;
}