Boris wrote:

When I send options_description to cout I would like to put an empty line between the caption and the options - something like:

Allowed options:

--help produce help message --compression arg set compression level

As : is automatically appended to the caption it's not possible to add \n. Is this what I'm trying to do supported?

Another question: Can the argument arg behind the --compression option above be changed to <arg>? I read at http://article.gmane.org/gmane.comp.lib.boost.user/38506 that it's not possible to replace arg with level but maybe putting <> around arg works somehow?

It is not possible. - Volodya