Closes #16

core/decode_database.cpp

@@ -89,12 +89,16 @@ namespace {
 DecodeDatabase::Storage::Storage(const std::vector<DecodeFrame> &definitions)
     : frames(definitions) {
     // Validate the complete snapshot before creating its lookup index.
-    for (const DecodeFrame &frame: frames)
+    std::unordered_set<FrameKey, FrameKeyHasher> keys;
+    keys.reserve(frames.size());
+    for (const DecodeFrame &frame: frames) {
         ValidateFrame(frame);
+        if (!keys.insert(frame.GetKey()).second)
+            throw std::invalid_argument("Duplicate runtime frame key");
+    }
     frameIndexByKey.reserve(frames.size());
     for (std::size_t index = 0U; index < frames.size(); ++index) {
-        if (!frameIndexByKey.emplace(frames[index].GetKey(), index).second)
-            throw std::invalid_argument("Duplicate runtime frame key");
+        frameIndexByKey.emplace(frames[index].GetKey(), index);
     }
 }