1 files changed, 174 insertions, 0 deletions
diff --git a/src/boost/libs/yap/test/deref.cpp b/src/boost/libs/yap/test/deref.cpp
new file mode 100644
index 00000000..137b51e8
--- /dev/null
+++ b/src/boost/libs/yap/test/deref.cpp
@@ -0,0 +1,174 @@
+// Copyright (C) 2016-2018 T. Zachary Laine
+//
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+#include <boost/yap/expression.hpp>
+
+#include <boost/mpl/assert.hpp>
+
+#include <boost/test/minimal.hpp>
+
+
+template<typename T>
+using term = boost::yap::terminal<boost::yap::expression, T>;
+
+template<typename T>
+using ref = boost::yap::expression_ref<boost::yap::expression, T>;
+
+namespace yap = boost::yap;
+namespace bh = boost::hana;
+
+
+template<boost::yap::expr_kind Kind, typename Tuple>
+struct user_expr
+{
+    static boost::yap::expr_kind const kind = Kind;
+
+    Tuple elements;
+};
+
+BOOST_YAP_USER_BINARY_OPERATOR(plus, user_expr, user_expr)
+
+template<typename T>
+using user_term = boost::yap::terminal<user_expr, T>;
+
+template<typename T>
+using user_ref = boost::yap::expression_ref<user_expr, T>;
+
+
+int test_main(int, char * [])
+{
+    {
+        term<double> unity = {{1.0}};
+        using plus_expr_type = yap::expression<
+            yap::expr_kind::plus,
+            bh::tuple<ref<term<double> &>, term<int>>>;
+
+        plus_expr_type plus_expr = unity + term<int>{{1}};
+
+        {
+            ref<term<double> &> ref = bh::front(plus_expr.elements);
+            BOOST_MPL_ASSERT((std::is_same<
+                              decltype(yap::deref(std::move(ref))),
+                              term<double> &>));
+            BOOST_CHECK(yap::value(ref) == 1.0);
+        }
+
+        {
+            ref<term<double> &> ref = bh::front(plus_expr.elements);
+            BOOST_MPL_ASSERT(
+                (std::is_same<decltype(yap::deref(ref)), term<double> &>));
+            BOOST_CHECK(yap::value(ref) == 1.0);
+        }
+
+        {
+            ref<term<double> &> const ref = bh::front(plus_expr.elements);
+            BOOST_MPL_ASSERT(
+                (std::is_same<decltype(yap::deref(ref)), term<double> &>));
+            BOOST_CHECK(yap::value(ref) == 1.0);
+        }
+
+        {
+            term<double> const unity = {{1.0}};
+            yap::expression<
+                yap::expr_kind::plus,
+                bh::tuple<ref<term<double> const &>, term<int>>>
+                plus_expr = unity + term<int>{{1}};
+
+            {
+                ref<term<double> const &> ref = bh::front(plus_expr.elements);
+                BOOST_MPL_ASSERT((std::is_same<
+                                  decltype(yap::deref(std::move(ref))),
+                                  term<double> const &>));
+                BOOST_CHECK(yap::value(ref) == 1.0);
+            }
+
+            {
+                ref<term<double> const &> ref = bh::front(plus_expr.elements);
+                BOOST_MPL_ASSERT((std::is_same<
+                                  decltype(yap::deref(ref)),
+                                  term<double> const &>));
+                BOOST_CHECK(yap::value(ref) == 1.0);
+            }
+
+            {
+                ref<term<double> const &> const ref =
+                    bh::front(plus_expr.elements);
+                BOOST_MPL_ASSERT((std::is_same<
+                                  decltype(yap::deref(ref)),
+                                  term<double> const &>));
+                BOOST_CHECK(yap::value(ref) == 1.0);
+            }
+        }
+    }
+
+    {
+        user_term<double> unity = {{1.0}};
+        using plus_expr_type = user_expr<
+            yap::expr_kind::plus,
+            bh::tuple<user_ref<user_term<double> &>, user_term<int>>>;
+
+        plus_expr_type plus_expr = unity + user_term<int>{{1}};
+
+        {
+            user_ref<user_term<double> &> ref = bh::front(plus_expr.elements);
+            BOOST_MPL_ASSERT((std::is_same<
+                              decltype(yap::deref(std::move(ref))),
+                              user_term<double> &>));
+            BOOST_CHECK(yap::value(ref) == 1.0);
+        }
+
+        {
+            user_ref<user_term<double> &> ref = bh::front(plus_expr.elements);
+            BOOST_MPL_ASSERT(
+                (std::is_same<decltype(yap::deref(ref)), user_term<double> &>));
+            BOOST_CHECK(yap::value(ref) == 1.0);
+        }
+
+        {
+            user_ref<user_term<double> &> const ref =
+                bh::front(plus_expr.elements);
+            BOOST_MPL_ASSERT(
+                (std::is_same<decltype(yap::deref(ref)), user_term<double> &>));
+            BOOST_CHECK(yap::value(ref) == 1.0);
+        }
+
+        {
+            user_term<double> const unity = {{1.0}};
+            user_expr<
+                yap::expr_kind::plus,
+                bh::tuple<user_ref<user_term<double> const &>, user_term<int>>>
+                plus_expr = unity + user_term<int>{{1}};
+
+            {
+                user_ref<user_term<double> const &> ref =
+                    bh::front(plus_expr.elements);
+                BOOST_MPL_ASSERT((std::is_same<
+                                  decltype(yap::deref(std::move(ref))),
+                                  user_term<double> const &>));
+                BOOST_CHECK(yap::value(ref) == 1.0);
+            }
+
+            {
+                user_ref<user_term<double> const &> ref =
+                    bh::front(plus_expr.elements);
+                BOOST_MPL_ASSERT((std::is_same<
+                                  decltype(yap::deref(ref)),
+                                  user_term<double> const &>));
+                BOOST_CHECK(yap::value(ref) == 1.0);
+            }
+
+            {
+                user_ref<user_term<double> const &> const ref =
+                    bh::front(plus_expr.elements);
+                BOOST_MPL_ASSERT((std::is_same<
+                                  decltype(yap::deref(ref)),
+                                  user_term<double> const &>));
+                BOOST_CHECK(yap::value(ref) == 1.0);
+            }
+        }
+    }
+
+    return 0;
+}