-std::ostream& operator<<(std::ostream& os, const StringPiece piece);
-std::ostream& operator<<(std::ostream& os, const MutableStringPiece piece);
+inline std::ostream& operator<<(std::ostream& os,
+ const StringPiece piece) {
+ os.write(piece.start(), piece.size());
+ return os;
+}
+
+inline std::ostream& operator<<(std::ostream& os,
+ const MutableStringPiece piece) {
+ os.write(piece.start(), piece.size());
+ return os;
+}