is that functions/functors passed to Thrust algorithms
      are actual compiled C++ functions whereas for Boost.Compute these form expression
      objects which are then translated into C99 code which is then compiled for
      OpenCL.
    </p>
<h4>
<a name="boost_compute.faq.h6"></a>
      <span class="phrase"><a name="boost_compute.faq.why_not_target_cuda_and_or_support_multiple_back_ends_"></a></span><a class="link" href="faq.html#boost_compute.faq.why_not_target_cuda_and_or_support_multiple_back_ends_