text: # Software License Agreement (BSD License)
  #
  # Copyright (c) 2013, Open Source Robotics Foundation, Inc.
  # All rights reserved.
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions
  # are met:
  #
  #  * Redistributions of source code must retain the above copyright
  #    notice, this list of conditions and the following disclaimer.
  #  * Redistributions in binary form must reproduce the above
  #    copyright notice, this list of conditions and the following
  #    disclaimer in the documentation and/or other materials provided
  #    with the distribution.
  #  * Neither the name of Open Source Robotics Foundation, Inc. nor
  #    the names of its contributors may be used to endorse or promote
  #    products derived from this software without specific prior
  #    written permission.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  # FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  # COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  # INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  # BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  # LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  # ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  # POSSIBILITY OF SUCH DAMAGE.
  
  from __future__ import print_function
  
  import os
  import re
  
  
  def get_metapackage_cmake_template_path():
      '''
      Returns the location of the metapackage CMakeLists.txt CMake template.
  
      :returns: ``str`` location of the metapackage CMakeLists.txt CMake template
      '''
      rel_path = os.path.join('templates', 'metapackage.cmake.in')
      return os.path.join(os.path.dirname(__file__), rel_path)
  
  
  def configure_file(template_file, environment):
      '''
      Evaluate a .in template file used in CMake with configure_file().
  
      :param template_file: path to the template, ``str``
      :param environment: dictionary of placeholders to substitute,
        ``dict``
      :returns: string with evaluates template
      :raises: KeyError for placeholders in the template which are not
        in the environment
      '''
      with open(template_file, 'r') as f:
          template = f.read()
          return configure_string(template, environment)
  
  
  def configure_string(template, environment):
      '''
      Substitute variables enclosed by @ characters.
  
      :param template: the template, ``str``
      :param environment: dictionary of placeholders to substitute,
        ``dict``
      :returns: string with evaluates template
      :raises: KeyError for placeholders in the template which are not
        in the environment
      '''
      def substitute(match):
          var = match.group(0)[1:-1]
          return environment[var]
      return re.sub('\@[a-zA-Z0-9_]+\@', substitute, template)
  