def addArguments(string, args, joiner='_'):
    """
        args is an array of ArgumentToAdd.
    """
    for arg in args:
        string = string + ('' if arg.val is None or arg.val is False or 
            hasattr(arg.val, '__len__') and len(arg.val) == 0 else joiner +
            arg.transform())
    return string
