text: ##############################################################################
  # Copyright (c) 2013-2018, Lawrence Livermore National Security, LLC.
  # Produced at the Lawrence Livermore National Laboratory.
  #
  # This file is part of Spack.
  # Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
  # LLNL-CODE-647188
  #
  # For details, see https://github.com/spack/spack
  # Please also see the NOTICE and LICENSE files for our notice and the LGPL.
  #
  # This program is free software; you can redistribute it and/or modify
  # it under the terms of the GNU Lesser General Public License (as
  # published by the Free Software Foundation) version 2.1, February 1999.
  #
  # This program is distributed in the hope that it will be useful, but
  # WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
  # conditions of the GNU Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this program; if not, write to the Free Software
  # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  ##############################################################################
  from spack import *
  import sys
  
  
  class ModernWheel(CMakePackage):
      """C++ utility collection. Provides various facilities of common use in
      modern codebases like dynamic linking helpers, loadable plugins facilities
      and misc patterns."""
  
      homepage = "https://github.com/alalazo/modern_wheel"
      url      = "https://github.com/alalazo/modern_wheel/archive/1.2.tar.gz"
  
      version('1.2', 'dc440099c52b6af3b8ddff6fd7730aff')
      version('1.1', '289455239ad19497b7db55aacb299ca8')
      version('1.0', '503dc3e7da2b422c4295e4afcba09dfb')
  
      variant('shared', default=True,
              description='Enables the build of shared libraries')
      # Test implementation files cause some issues on darwin,
      # needs to be investigated.
      variant('test',   default=sys.platform != 'darwin',
              description='Enables the build of unit tests')
  
      # FindBoost shipped with CMake up to version 3.10.2 (latest one
      # up to now) is known to be unable to detect Boost >= 1.66.0.
      # This issue will be probably fixed in CMake >= 3.11.0:
      # https://gitlab.kitware.com/cmake/cmake/issues/17575
      # Until then, just assume that we cannot correctly configure
      # ModernWheel with Boost >= 1.66.0.
      depends_on('boost           +system +filesystem', when='@:1.1.999')
      depends_on('boost@:1.65.999 +system +filesystem', when='@1.2:')
  
      def cmake_args(self):
          spec = self.spec
          return [
              '-DBUILD_UNIT_TEST:BOOL={0}'.format(
                  'ON' if '+test' in spec else 'OFF'),
              '-DBUILD_SHARED_LIBS:BOOL={0}'.format(
                  'ON' if '+shared' in spec else 'OFF'),
          ]
  