1 files changed, 5 insertions, 0 deletions
diff --git a/Firestore/core/src/firebase/firestore/util/comparison.h b/Firestore/core/src/firebase/firestore/util/comparison.h
index d7f4dfd..a7d7944 100644
--- a/Firestore/core/src/firebase/firestore/util/comparison.h
+++ b/Firestore/core/src/firebase/firestore/util/comparison.h
@@ -86,6 +86,11 @@ struct Comparator<absl::string_view> {
                   const absl::string_view& right) const;
 };
 
+template <>
+struct Comparator<std::string> {
+  bool operator()(const std::string& left, const std::string& right) const;
+};
+
 /** Compares two bools: false < true. */
 template <>
 struct Comparator<bool> : public std::less<bool> {};