Add value list support to mp_min_element, mp_max_element. Fixes #87.

test/mp_max_element_q_2.cpp

@@ -0,0 +1,61 @@
+// Copyright 2017, 2023 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/mp11/algorithm.hpp>
+#include <boost/mp11/list.hpp>
+#include <boost/mp11/integral.hpp>
+
+#if !defined(BOOST_MP11_HAS_TEMPLATE_AUTO)
+
+#pragma message("Test skipped because BOOST_MP11_HAS_TEMPLATE_AUTO is not defined")
+int main() {}
+
+#else
+
+#include <boost/core/lightweight_test_trait.hpp>
+
+template<auto... A> struct V1 {};
+template<int... I> struct V2 {};
+
+int main()
+{
+    using boost::mp11::mp_max_element_q;
+    using boost::mp11::mp_less;
+    using boost::mp11::mp_int;
+    using boost::mp11::mp_quote;
+
+    using Q = mp_quote<mp_less>;
+
+    {
+        using L1 = V1<1>;
+        BOOST_TEST_TRAIT_SAME(mp_max_element_q<L1, Q>, mp_int<1>);
+
+        using L2 = V1<2, 4, 3, 1>;
+        BOOST_TEST_TRAIT_SAME(mp_max_element_q<L2, Q>, mp_int<4>);
+
+        using L3 = V1<2, 1, 2, 3>;
+        BOOST_TEST_TRAIT_SAME(mp_max_element_q<L3, Q>, mp_int<3>);
+
+        using L4 = V1<-1, 1u, -2, 2u>;
+        BOOST_TEST_TRAIT_SAME(mp_max_element_q<L4, Q>, std::integral_constant<unsigned, 2>);
+    }
+
+    {
+        using L1 = V2<1>;
+        BOOST_TEST_TRAIT_SAME(mp_max_element_q<L1, Q>, mp_int<1>);
+
+        using L2 = V2<2, 4, 3, 1>;
+        BOOST_TEST_TRAIT_SAME(mp_max_element_q<L2, Q>, mp_int<4>);
+
+        using L3 = V2<2, 1, 2, 3>;
+        BOOST_TEST_TRAIT_SAME(mp_max_element_q<L3, Q>, mp_int<3>);
+
+        using L4 = V2<-1, 1, -2, 2>;
+        BOOST_TEST_TRAIT_SAME(mp_max_element_q<L4, Q>, mp_int<2>);
+    }
+
+    return boost::report_errors();
+}
+
+#endif