ceph/src/boost/libs/hana/test/detail/index_if.cpp

   1 // Copyright Louis Dionne 2013-2016
   2 // Distributed under the Boost Software License, Version 1.0.
   3 // (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
   4
   5 #include <boost/hana/detail/index_if.hpp>
   6
   7 #include <boost/hana/bool.hpp>
   8 namespace hana = boost::hana;
   9
  10
  11 template <int i>
  12 struct x { };
  13
  14 template <int n>
  15 struct Find {
  16     template <int i>
  17     constexpr auto operator()(x<i> const&) const
  18     { return hana::bool_c<n == i>; }
  19 };
  20
  21 struct NotFound {
  22     template <typename T>
  23     constexpr auto operator()(T const&) const
  24     { return hana::false_c; }
  25 };
  26
  27 struct Undefined;
  28
  29 int main() {
  30     {
  31         using Pack = hana::detail::pack<>;
  32         static_assert(hana::detail::index_if<Undefined, Pack>::value == 0, "");
  33     }
  34
  35     {
  36         using Pack = hana::detail::pack<x<0>>;
  37         static_assert(hana::detail::index_if<Find<0>, Pack>::value == 0, "");
  38         static_assert(hana::detail::index_if<NotFound, Pack>::value == 1, "");
  39     }
  40
  41     {
  42         using Pack = hana::detail::pack<x<0>, x<1>>;
  43         static_assert(hana::detail::index_if<Find<0>, Pack>::value == 0, "");
  44         static_assert(hana::detail::index_if<Find<1>, Pack>::value == 1, "");
  45         static_assert(hana::detail::index_if<NotFound, Pack>::value == 2, "");
  46     }
  47
  48     {
  49         using Pack = hana::detail::pack<x<0>, x<1>, x<2>>;
  50         static_assert(hana::detail::index_if<Find<0>, Pack>::value == 0, "");
  51         static_assert(hana::detail::index_if<Find<1>, Pack>::value == 1, "");
  52         static_assert(hana::detail::index_if<Find<2>, Pack>::value == 2, "");
  53         static_assert(hana::detail::index_if<NotFound, Pack>::value == 3, "");
  54     }
  55
  56     {
  57         using Pack = hana::detail::pack<x<0>, x<1>, x<2>, x<3>>;
  58         static_assert(hana::detail::index_if<Find<0>, Pack>::value == 0, "");
  59         static_assert(hana::detail::index_if<Find<1>, Pack>::value == 1, "");
  60         static_assert(hana::detail::index_if<Find<2>, Pack>::value == 2, "");
  61         static_assert(hana::detail::index_if<Find<3>, Pack>::value == 3, "");
  62         static_assert(hana::detail::index_if<NotFound, Pack>::value == 4, "");
  63     }
  64
  65     {
  66         using Pack = hana::detail::pack<x<0>, x<1>, x<2>, x<3>, x<4>>;
  67         static_assert(hana::detail::index_if<Find<0>, Pack>::value == 0, "");
  68         static_assert(hana::detail::index_if<Find<1>, Pack>::value == 1, "");
  69         static_assert(hana::detail::index_if<Find<2>, Pack>::value == 2, "");
  70         static_assert(hana::detail::index_if<Find<3>, Pack>::value == 3, "");
  71         static_assert(hana::detail::index_if<Find<4>, Pack>::value == 4, "");
  72         static_assert(hana::detail::index_if<NotFound, Pack>::value == 5, "");
  73     }
  74 }