<br clear="all">Hello,<br><br>I&#39;m wondering if there is a possibility to make program_options library to notify me automatically when option with no value is passed?<br>As far as I understand this feature exists only for options with defined value_semantic. But this means I must permit passing a value for such options. Say, I make an option with zero_tokens() semantics so it can be passed without value and throw an error if some value was provided. <br>

Unfortunately, this doesn&#39;t solve the problem if you have positional options. In that case a positional option  following a no-value option will be parsed as this option&#39;s value.<br>I can&#39;t set notifier for options with no value? This is something not understandable. I even think of some patch to be added to the lib.<br>

<br>Regards,<br>Dmitriy.<br>