/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2021, Individual contributors, see AUTHORS file     |
   | See: https://www.mrpt.org/Authors - All rights reserved.               |
   | Released under BSD License. See: https://www.mrpt.org/License          |
   +------------------------------------------------------------------------+ */


/******************************************************************************
 *
 *  file:  OptionalUnlabeledTracker.h
 *
 *  Copyright (c) 2005, Michael E. Smoot .
 *  All rights reverved.
 *
 *  See the file COPYING in the top directory of this distribution for
 *  more information.
 *
 *  THE SOFTWARE IS PROVIDED _AS IS_, WITHOUT WARRANTY OF ANY KIND, EXPRESS
 *  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 *  THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 *  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 *  DEALINGS IN THE SOFTWARE.
 *
 *****************************************************************************/


#pragma once

#include <string>

namespace TCLAP {

template <class DUMMY = int>
class OptionalUnlabeledTracker
{

	public:

		static void check( bool req, const std::string& argName );

		static void gotOptional() { alreadyOptionalRef() = true; }

		static bool& alreadyOptional() { return alreadyOptionalRef(); }

	private:

		static bool& alreadyOptionalRef() { static bool ct = false; return ct; }
};


template <class DUMMY>
void OptionalUnlabeledTracker<DUMMY>::check( bool req, const std::string& argName )
{
    if ( OptionalUnlabeledTracker::alreadyOptional() )
        throw( SpecificationException(
	"You can't specify ANY Unlabeled Arg following an optional Unlabeled Arg",
	                argName ) );

    if ( !req )
        OptionalUnlabeledTracker::gotOptional();
}


} // namespace TCLAP

