.. _program_listing_file_include_rcpputils_time.hpp:

Program Listing for File time.hpp
=================================

|exhale_lsh| :ref:`Return to documentation for file <file_include_rcpputils_time.hpp>` (``include/rcpputils/time.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // Copyright 2021 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.
   
   #ifndef RCPPUTILS__TIME_HPP_
   #define RCPPUTILS__TIME_HPP_
   
   #include <chrono>
   
   namespace rcpputils
   {
   
   
   template<typename DurationRepT, typename DurationT>
   std::chrono::nanoseconds convert_to_nanoseconds(
     const std::chrono::duration<DurationRepT, DurationT> & time)
   {
     constexpr auto ns_max_as_double =
       std::chrono::duration_cast<std::chrono::duration<double, std::chrono::nanoseconds::period>>(
       std::chrono::nanoseconds::max());
     if (time > ns_max_as_double) {
       throw std::invalid_argument{
               "time must be less than std::chrono::nanoseconds::max()"};
     }
   
     constexpr auto ns_min_as_double =
       std::chrono::duration_cast<std::chrono::duration<double, std::chrono::nanoseconds::period>>(
       std::chrono::nanoseconds::min());
     if (time < ns_min_as_double) {
       throw std::invalid_argument{
               "time must be bigger than std::chrono::nanoseconds::min()"};
     }
   
     return std::chrono::duration_cast<std::chrono::nanoseconds>(time);
   }
   
   }  // namespace rcpputils
   
   #endif  // RCPPUTILS__TIME_HPP_