old_contents: # Copyright 2015-2017 Open Source Robotics Foundation, Inc.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  import argparse
  import os
  import sys
  
  from launch import LaunchDescriptor
  from launch.launcher import DefaultLauncher
  from launch.loader import load_launch_file
  
  
  def file_exists(filename):
      if not os.path.isfile(filename):
          raise argparse.ArgumentError("'%s' does not exist" % filename)
      return filename
  
  
  def main(argv=sys.argv[1:]):
      parser = argparse.ArgumentParser(
          description='Launch the processes specified in a launch file.')
      parser.add_argument(
          'launch_file',
          type=file_exists,
          nargs='+',
          help='The launch file.')
      parser.add_argument(
          '--args',
          metavar='arg',
          type=str,
          nargs='+',
          help='An argument to the launch file (e.g., arg_name:=value). All '
               'arguments will be passed to each launch file.')
      args = parser.parse_args(argv)
  
      launcher = DefaultLauncher()
      for launch_file in args.launch_file:
          launch_descriptor = LaunchDescriptor()
          load_launch_file(args.launch_file, launch_descriptor, args.args)
          launcher.add_launch_descriptor(launch_descriptor)
      rc = launcher.launch()
      return rc
  
  
  if __name__ == '__main__':
      sys.exit(main())
  
new_contents: # Copyright 2015-2017 Open Source Robotics Foundation, Inc.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  import argparse
  import os
  import sys
  
  from launch import LaunchDescriptor
  from launch.launcher import DefaultLauncher
  from launch.loader import load_launch_file
  
  
  def file_exists(filename):
      if not os.path.isfile(filename):
          raise argparse.ArgumentError("'%s' does not exist" % filename)
      return filename
  
  
  def main(argv=sys.argv[1:]):
      parser = argparse.ArgumentParser(
          description='Launch the processes specified in a launch file.')
      parser.add_argument(
          'launch_file',
          type=file_exists,
          nargs='+',
          help='The launch file.')
      parser.add_argument(
          '--args',
          metavar='arg',
          type=str,
          nargs='+',
          help='An argument to the launch file (e.g., arg_name:=value). All '
               'arguments will be passed to each launch file.')
      args = parser.parse_args(argv)
  
      launcher = DefaultLauncher()
      for launch_file in args.launch_file:
          launch_descriptor = LaunchDescriptor()
          load_launch_file(launch_file, launch_descriptor, args.args)
          launcher.add_launch_descriptor(launch_descriptor)
      rc = launcher.launch()
      return rc
  
  
  if __name__ == '__main__':
      sys.exit(main())
  
subject: Fix 62 (#63)