ceph/src/boost/libs/mpl/include/boost/mpl/index_if.hpp

   1
   2 #ifndef BOOST_MPL_INDEX_IF_HPP_INCLUDED
   3 #define BOOST_MPL_INDEX_IF_HPP_INCLUDED
   4
   5 // Copyright Eric Friedman 2003
   6 //
   7 // Distributed under the Boost Software License, Version 1.0.
   8 // (See accompanying file LICENSE_1_0.txt or copy at
   9 // http://www.boost.org/LICENSE_1_0.txt)
  10 //
  11 // See http://www.boost.org/libs/mpl for documentation.
  12
  13 // $Id$
  14 // $Date$
  15 // $Revision$
  16
  17 #include <boost/mpl/aux_/find_if_pred.hpp>
  18 #include <boost/mpl/begin_end.hpp>
  19 #include <boost/mpl/if.hpp>
  20 #include <boost/mpl/int.hpp>
  21 #include <boost/mpl/iter_fold_if.hpp>
  22 #include <boost/mpl/next.hpp>
  23 #include <boost/mpl/void.hpp>
  24 #include <boost/mpl/aux_/na_spec.hpp>
  25 #include <boost/mpl/aux_/lambda_support.hpp>
  26 #include <boost/type_traits/is_same.hpp>
  27
  28 namespace boost { namespace mpl {
  29
  30 template<
  31       typename BOOST_MPL_AUX_NA_PARAM(Sequence)
  32     , typename BOOST_MPL_AUX_NA_PARAM(Predicate)
  33     >
  34 struct index_if
  35 {
  36     typedef typename iter_fold_if<
  37           Sequence
  38         , int_<0>
  39         , next<>
  40         , aux::find_if_pred<Predicate>
  41         >::type result_;
  42
  43     typedef typename end<Sequence>::type not_found_;
  44     typedef typename first<result_>::type result_index_;
  45     typedef typename second<result_>::type result_iterator_;
  46
  47     typedef typename if_<
  48           is_same< result_iterator_,not_found_ >
  49         , void_
  50         , result_index_
  51         >::type type;
  52
  53     BOOST_MPL_AUX_LAMBDA_SUPPORT(2,index_if,(Sequence,Predicate))
  54 };
  55
  56 BOOST_MPL_AUX_NA_SPEC(2, index_if)
  57
  58 }}
  59
  60 #endif // BOOST_MPL_INDEX_IF_HPP_INCLUDED