diff --git a/include/r3_str.h b/include/r3_str.h
index 967a1ef..f87f115 100644
--- a/include/r3_str.h
+++ b/include/r3_str.h
@@ -23,8 +23,6 @@ int r3_slug_count(const char * needle, int len, char **errstr);
 
 char * r3_inside_slug(const char * needle, int needle_len, char *offset, char **errstr);
 
-void print_indent(int level);
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/str.c b/src/str.c
index f21fa57..826d797 100644
--- a/src/str.c
+++ b/src/str.c
@@ -11,6 +11,7 @@
 #include <assert.h>
 #include "r3.h"
 #include "r3_str.h"
+#include "str.h"
 #include "slug.h"
 #include "zmalloc.h"
 
diff --git a/src/str.h b/src/str.h
new file mode 100644
index 0000000..e97e94e
--- /dev/null
+++ b/src/str.h
@@ -0,0 +1,14 @@
+#ifndef R3_STR_INTERN_H
+#define R3_STR_INTERN_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void print_indent(int level);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif