libs/hana/test/experimental/types/unpack.cpp

   1 // Copyright Louis Dionne 2013-2017
   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/assert.hpp>
   6 #include <boost/hana/equal.hpp>
   7 #include <boost/hana/experimental/types.hpp>
   8 #include <boost/hana/type.hpp>
   9 #include <boost/hana/unpack.hpp>
  10
  11 #include <laws/base.hpp>
  12 namespace hana = boost::hana;
  13
  14
  15 template <typename ...>
  16 struct mf { struct type; };
  17
  18 template <int> struct x;
  19
  20 int main() {
  21     // with a Metafunction
  22     {
  23         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  24             hana::unpack(hana::experimental::types<>{}, hana::metafunction<mf>),
  25             hana::type_c<mf<>::type>
  26         ));
  27
  28         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  29             hana::unpack(hana::experimental::types<x<0>>{}, hana::metafunction<mf>),
  30             hana::type_c<mf<x<0>>::type>
  31         ));
  32
  33         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  34             hana::unpack(hana::experimental::types<x<0>, x<1>>{}, hana::metafunction<mf>),
  35             hana::type_c<mf<x<0>, x<1>>::type>
  36         ));
  37
  38         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  39             hana::unpack(hana::experimental::types<x<0>, x<1>, x<2>>{}, hana::metafunction<mf>),
  40             hana::type_c<mf<x<0>, x<1>, x<2>>::type>
  41         ));
  42
  43         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  44             hana::unpack(hana::experimental::types<x<0>, x<1>, x<2>, x<3>>{}, hana::metafunction<mf>),
  45             hana::type_c<mf<x<0>, x<1>, x<2>, x<3>>::type>
  46         ));
  47
  48         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  49             hana::unpack(hana::experimental::types<x<0>, x<1>, x<2>, x<3>, x<4>>{}, hana::metafunction<mf>),
  50             hana::type_c<mf<x<0>, x<1>, x<2>, x<3>, x<4>>::type>
  51         ));
  52     }
  53
  54     // with a non-Metafunction
  55     {
  56         auto f = hana::test::_injection<0>{};
  57
  58         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  59             hana::unpack(hana::experimental::types<>{}, f),
  60             f()
  61         ));
  62
  63         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  64             hana::unpack(hana::experimental::types<x<0>>{}, f),
  65             f(hana::type_c<x<0>>)
  66         ));
  67
  68         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  69             hana::unpack(hana::experimental::types<x<0>, x<1>>{}, f),
  70             f(hana::type_c<x<0>>, hana::type_c<x<1>>)
  71         ));
  72
  73         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  74             hana::unpack(hana::experimental::types<x<0>, x<1>, x<2>>{}, f),
  75             f(hana::type_c<x<0>>, hana::type_c<x<1>>, hana::type_c<x<2>>)
  76         ));
  77
  78         BOOST_HANA_CONSTANT_CHECK(hana::equal(
  79             hana::unpack(hana::experimental::types<x<0>, x<1>, x<2>, x<3>>{}, f),
  80             f(hana::type_c<x<0>>, hana::type_c<x<1>>, hana::type_c<x<2>>, hana::type_c<x<3>>)
  81         ));
  82     }
  83 }