Merge pull request #32 from NAThompson/develop

Add .cbegin() and .cend().

Author: glenfe

include/boost/circular_buffer/base.hpp

@@ -287,6 +287,7 @@ private empty_value<Alloc>
     */
     const_iterator begin() const BOOST_NOEXCEPT { return const_iterator(this, empty() ? 0 : m_first); }
 
+    const_iterator cbegin() const BOOST_NOEXCEPT { return begin(); }
     //! Get the const iterator pointing to the end of the <code>circular_buffer</code>.
     /*!
         \return A const random access iterator pointing to the element "one behind" the last element of the <code>
@@ -303,6 +304,7 @@ private empty_value<Alloc>
     */
     const_iterator end() const BOOST_NOEXCEPT { return const_iterator(this, 0); }
 
+    const_iterator cend() const BOOST_NOEXCEPT { return end(); }
     //! Get the iterator pointing to the beginning of the "reversed" <code>circular_buffer</code>.
     /*!
         \return A reverse random access iterator pointing to the last element of the <code>circular_buffer</code>.

test/base_test.cpp

@@ -17,19 +17,23 @@ void iterator_constructor_and_assign_test() {
 
     circular_buffer<MyInteger> cb(4, 3);
     circular_buffer<MyInteger>::iterator it = cb.begin();
+    circular_buffer<MyInteger>::const_iterator cit2 = cb.cbegin();
     circular_buffer<MyInteger>::iterator itCopy;
     itCopy = it;
     it = it;
     circular_buffer<MyInteger>::const_iterator cit;
     cit = it;
     circular_buffer<MyInteger>::const_iterator end1 = cb.end();
     circular_buffer<MyInteger>::const_iterator end2 = end1;
+    circular_buffer<MyInteger>::const_iterator end3 = cb.cend();
 
     BOOST_TEST(itCopy == it);
     BOOST_TEST(cit == it);
     BOOST_TEST(end1 == end2);
     BOOST_TEST(it != end1);
     BOOST_TEST(cit != end2);
+    BOOST_TEST(cit2 == it);
+    BOOST_TEST(end3 == end1);
 }
 
 void iterator_reference_test() {