Add mp_find_index.

test/mp_find_index.cpp

@@ -0,0 +1,63 @@
+
+//  Copyright 2015 Peter Dimov.
+//
+// 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/mp11/algorithm.hpp>
+#include <boost/mp11/list.hpp>
+#include <boost/mp11/integral.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <type_traits>
+#include <tuple>
+#include <utility>
+
+struct X1 {};
+struct X2 {};
+struct X3 {};
+
+int main()
+{
+    using boost::mp_list;
+    using boost::mp_find_index;
+    using boost::mp_size_t;
+
+    {
+        using L1 = mp_list<>;
+
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L1, void>, mp_size_t<0>>));
+
+        using L2 = mp_list<X1, X2, X2, X3, X3, X3>;
+
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L2, void>, mp_size_t<6>>));
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L2, X1>, mp_size_t<0>>));
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L2, X2>, mp_size_t<1>>));
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L2, X3>, mp_size_t<3>>));
+    }
+
+    {
+        using L3 = std::tuple<>;
+
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L3, void>, mp_size_t<0>>));
+
+        using L4 = std::tuple<X1, X2, X2, X3, X3, X3>;
+
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L4, void>, mp_size_t<6>>));
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L4, X1>, mp_size_t<0>>));
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L4, X2>, mp_size_t<1>>));
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L4, X3>, mp_size_t<3>>));
+    }
+
+    {
+        using L5 = std::pair<X1, X2>;
+
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L5, void>, mp_size_t<2>>));
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L5, X1>, mp_size_t<0>>));
+        BOOST_TEST_TRAIT_TRUE((std::is_same<mp_find_index<L5, X2>, mp_size_t<1>>));
+    }
+
+    return boost::report_errors();
+}