ring: add pre cpp17 take() fn

1 files changed, 9 insertions, 2 deletions

diff --git a/ring.h b/ring.h
index 3658ec4..43c3fca 100644
--- a/ring.h
+++ b/ring.h
@@ -99,12 +99,19 @@ class ring {
 #if __cplusplus >= 201703L
   constexpr std::optional<T> take() {
     if (!is_empty()) {
-      const std::optional<T> kRet = std::move(vals[m_rc & kMASK]);
+      std::optional<T> ret = std::move(vals[m_rc & kMASK]);
       pop();
-      return kRet;
+      return ret;
     }
     return std::nullopt;
   }
+#else
+  constexpr T take() {
+    assert(!is_empty());
+    T ret = std::move(vals[m_rc & kMASK]);
+    pop();
+    return ret;
+  }
 #endif
 
   // -- INTERNAL ---------------------------------------------------------------