table: make FIB and StrategyChoice iterators default-constructible
They were previously not default-constructible when compiled with gcc 4.8.4.
refs #3882
Change-Id: I2431c869fb61b7adbe83d5551705981bf8618280
diff --git a/core/asserts.hpp b/core/asserts.hpp
new file mode 100644
index 0000000..cef39b4
--- /dev/null
+++ b/core/asserts.hpp
@@ -0,0 +1,67 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2016, Regents of the University of California,
+ * Arizona Board of Regents,
+ * Colorado State University,
+ * University Pierre & Marie Curie, Sorbonne University,
+ * Washington University in St. Louis,
+ * Beijing Institute of Technology,
+ * The University of Memphis.
+ *
+ * This file is part of NFD (Named Data Networking Forwarding Daemon).
+ * See AUTHORS.md for complete list of NFD authors and contributors.
+ *
+ * NFD is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NFD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * NFD, e.g., in COPYING.md file. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef NFD_CORE_ASSERTS_HPP
+#define NFD_CORE_ASSERTS_HPP
+
+#include "common.hpp"
+#include <boost/concept/assert.hpp>
+#include <boost/concept_check.hpp>
+#include <type_traits>
+
+namespace nfd {
+namespace detail {
+
+// As of Boost 1.54.0, the internal implementation of BOOST_CONCEPT_ASSERT does not allow
+// multiple assertions on the same line, so we have to combine multiple concepts together.
+
+template<typename T>
+class StlForwardIteratorConcept : public boost::ForwardIterator<T>
+ , public boost::DefaultConstructible<T>
+{
+};
+
+} // namespace detail
+} // namespace nfd
+
+/** \brief assert T is default constructible
+ * \sa http://en.cppreference.com/w/cpp/concept/DefaultConstructible
+ */
+#define NFD_ASSERT_DEFAULT_CONSTRUCTIBLE(T) \
+ static_assert(std::is_default_constructible<T>::value, \
+ #T " must be default-constructible"); \
+ BOOST_CONCEPT_ASSERT((boost::DefaultConstructible<T>))
+
+/** \brief assert T is a forward iterator
+ * \sa http://en.cppreference.com/w/cpp/concept/ForwardIterator
+ * \note A forward iterator should be default constructible, but boost::ForwardIterator follows
+ * SGI standard which doesn't require DefaultConstructible, so a separate check is needed.
+ */
+#define NFD_ASSERT_FORWARD_ITERATOR(T) \
+ BOOST_CONCEPT_ASSERT((::nfd::detail::StlForwardIteratorConcept<T>)); \
+ static_assert(std::is_default_constructible<T>::value, \
+ #T " must be default-constructible")
+
+#endif // NFD_CORE_ASSERTS_HPP