@@ -13,14 +13,18 @@
  * Public License, either version 2 or 3, which can be found in the file
  * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
  * file.
  */
 
-#import "OFString.h"
+#ifndef OBJFW_OF_MUTABLE_STRING_H
+#define OBJFW_OF_MUTABLE_STRING_H
+
+#include "OFString.h"
 
 OF_ASSUME_NONNULL_BEGIN
 
+#ifdef __OBJC__
 /*!
  * @class OFMutableString OFString.h ObjFW/OFString.h
  *
  * @brief A class for storing and modifying strings.
  */
@@ -210,7 +214,10 @@
 /*!
  * @brief Converts the mutable string to an immutable string.
  */
 - (void)makeImmutable;
 @end
+#endif
 
 OF_ASSUME_NONNULL_END
+
+#endif