diff --git a/src/include/file_io.h b/src/include/file_io.h
index 8c228098e872d5941bb7b9b9f51ca3576ffa9b71..0a0aad2afb106f0de065f1c1dd9255bc81d5d362 100644
--- a/src/include/file_io.h
+++ b/src/include/file_io.h
@@ -82,8 +82,8 @@ class HDFFile {
    * \param fapl_id: `hid_t` File access property list identifier (default is `H5P_DEFAULT`).
    */
   HDFFile(
-	  std::string name, unsigned int flags = H5F_ACC_EXCL,
-	  hid_t fcpl_id = H5P_DEFAULT, hid_t fapl_id = H5P_DEFAULT
+	  std::string name, unsigned int flags=H5F_ACC_EXCL,
+	  hid_t fcpl_id=H5P_DEFAULT, hid_t fapl_id=H5P_DEFAULT
   );
 
   /*! \brief HDFFile instance destroyer.
@@ -104,8 +104,8 @@ class HDFFile {
    * \return hdf_file: `HDFFile *` Pointer to a new, open HDF5 file.
    */
   static HDFFile* from_schema(
-			      FileSchema &schema, std::string name, unsigned int flags = H5F_ACC_EXCL,
-			      hid_t fcpl_id = H5P_DEFAULT, hid_t fapl_id = H5P_DEFAULT
+			      FileSchema &schema, std::string name, unsigned int flags=H5F_ACC_EXCL,
+			      hid_t fcpl_id=H5P_DEFAULT, hid_t fapl_id=H5P_DEFAULT
   );
 
   /*! \brief Get current status.