diff --git a/src/util/io-util.hpp b/src/util/io-util.hpp
index 8fef79e..8d7b2a9 100644
--- a/src/util/io-util.hpp
+++ b/src/util/io-util.hpp
@@ -57,7 +57,7 @@
   template<typename T>
   static std::vector<T>
   load_directory(const std::string& dirPath,
-                 ndn::io::IoEncoding encoding = ndn::io::IoEncoding::BASE_64);
+                 ndn::io::IoEncoding encoding = ndn::io::IoEncoding::BASE64);
 
   static std::vector<ndn::Data>
   packetize_file(const fs::path& filePath,