Merge branch 'next-prior' of https://github.com/ecatmur/mpl into feature/issue-69

Apply change since C++11

include/boost/mpl/aux_/integral_wrapper.hpp

@@ -56,7 +56,8 @@ struct AUX_WRAPPER_NAME
 // have to #ifdef here: some compilers don't like the 'N + 1' form (MSVC),
 // while some other don't like 'value + 1' (Borland), and some don't like
 // either
-#if BOOST_WORKAROUND(__EDG_VERSION__, <= 243)
+#if BOOST_WORKAROUND(__EDG_VERSION__, <= 243) \
+    || __cplusplus >= 201103L
  private:
     BOOST_STATIC_CONSTANT(AUX_WRAPPER_VALUE_TYPE, next_value = BOOST_MPL_AUX_STATIC_CAST(AUX_WRAPPER_VALUE_TYPE, (N + 1)));
     BOOST_STATIC_CONSTANT(AUX_WRAPPER_VALUE_TYPE, prior_value = BOOST_MPL_AUX_STATIC_CAST(AUX_WRAPPER_VALUE_TYPE, (N - 1)));

test/Jamfile.v2

@@ -110,3 +110,5 @@ compile vector.cpp ;
 compile vector_c.cpp ;
 compile zip_view.cpp ;
 run string.cpp ;
+
+run issue_69.cpp ;

test/issue_69.cpp

@@ -0,0 +1,13 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0. 
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/mpl/integral_c.hpp>
+
+enum test { zero, one };
+
+int main()
+{
+    boost::mpl::integral_c<test, zero> m;
+    return m.value;
+}