diff --git a/src/normalizer.cpp b/src/normalizer.cpp
index 04af6c5..985a96c 100644
--- a/src/normalizer.cpp
+++ b/src/normalizer.cpp
@@ -102,8 +102,9 @@ std::unique_ptr<IRegex> ReplaceNormalizer::create_regex_(
 }
 
 std::string ReplaceNormalizer::normalize(const std::string& input) const {
-  if (!regex_)
+  if (!regex_) {
     return input;
+  }
 
   std::string result = input;
   auto matches = regex_->find_all(result);
diff --git a/src/pre_tokenizer.cpp b/src/pre_tokenizer.cpp
index 279fc39..7383d80 100644
--- a/src/pre_tokenizer.cpp
+++ b/src/pre_tokenizer.cpp
@@ -151,8 +151,9 @@ std::unique_ptr<IRegex> RegexPreTokenizer::create_regex_(
 
 std::vector<std::string> RegexPreTokenizer::pre_tokenize(
     const std::string& input) const {
-  if (!regex_)
+  if (!regex_) {
     return {};
+  }
 
   std::vector<std::string> results;
   auto matches = regex_->find_all(input);