Hello, just before feature freeze, I've committed some changes to program_options: - the command line parser was refactored. For historic reasons, it has its own data structures for representing options, and now it uses the options_description class. The internals were also cleaned up. - the 'implicit' option flag was removed. I've asked for comments on this some time ago, and no objections was raised. - some methods of 'options_description' and 'option_description' classes were removed - In 1.32, the 'additional_parser' could return only a single option. There's a new method of command line parser -- 'add_style_parser', which can be used to specify a function that can return vector<option>. This might be convenient, for example, for parsing response files Except for 'implicit' removal, those changes should not affect users of the library. However, I'd appreciate if user test the new version and report any problems. - Volodya