public static Integer Parse(string value, bool positive = true, bool hex = false)
{
if (!hex && !Regex.IsMatch(value, @"^-?[0-9]+$") ||
hex && !Regex.IsMatch(value, @"^-?[0-9a-fA-F]+$"))
{
throw new ArgumentException($"String was not in correct format: {value}.");
}
return(value.StartsWith("-") ? new Integer(Natural.Parse(value.Substring(1)), false) : new Integer(Natural.Parse(value), positive));
}