diff --git a/include/circ_elem_array.h b/include/circ_elem_array.h
index 607a7d9..9ab4f59 100644
--- a/include/circ_elem_array.h
+++ b/include/circ_elem_array.h
@@ -33,6 +33,10 @@ struct alignas(std::max_align_t) elem_array_head {
         return cc_.load(std::memory_order_acquire);
     }
 
+    u2_t cursor(void) const {
+        return wt_.load(std::memory_order_acquire);
+    }
+
     auto acquire(void) {
         while (lc_.exchange(1, std::memory_order_acquire)) {
             std::this_thread::yield();
@@ -62,6 +66,9 @@ public:
     using base_t = elem_array_head<BaseIntSize>;
     using head_t = elem_head;
 
+    using typename base_t::u1_t;
+    using typename base_t::u2_t;
+
     enum : std::size_t {
         head_size  = elem_array_head_size<BaseIntSize>,
         data_size  = DataSize,
@@ -95,6 +102,7 @@ public:
     using base_t::connect;
     using base_t::disconnect;
     using base_t::conn_count;
+    using base_t::cursor;
 
     void* acquire(void) {
         elem_t* el = elem(base_t::acquire());
@@ -116,12 +124,8 @@ public:
         base_t::commit();
     }
 
-    u2_t cursor(void) const {
-        return wt_.load(std::memory_order_acquire);
-    }
-
     void* take(u2_t cursor) {
-        return elem(index_of(cursor))->data_;
+        return elem(base_t::index_of(cursor))->data_;
     }
 
     void put(void* ptr) {
diff --git a/include/circ_queue.h b/include/circ_queue.h
index b294189..8c02ca5 100644
--- a/include/circ_queue.h
+++ b/include/circ_queue.h
@@ -19,7 +19,7 @@ public:
 
 private:
     array_t* elems_ = nullptr;
-    typename std::result_of<decltype(&array_t::cursor)(array_t)>::type cursor_ = 0;
+    typename array_t::u2_t cursor_ = 0;
     bool connected_ = false;
 
 public:
diff --git a/test/test_circ.cpp b/test/test_circ.cpp
index cff6abb..23860b3 100644
--- a/test/test_circ.cpp
+++ b/test/test_circ.cpp
@@ -144,7 +144,7 @@ struct test_cq;
 template <std::size_t D>
 struct test_cq<ipc::circ::elem_array<D>> {
     using ca_t = ipc::circ::elem_array<D>;
-    using cn_t = typename std::result_of<decltype(&ca_t::cursor)(ca_t)>::type;
+    using cn_t = typename ca_t::u2_t;
 
     ca_t* ca_;