diff --git a/libguile/inline.h b/libguile/inline.h
index 9cc23bada..1eae2e40f 100644
--- a/libguile/inline.h
+++ b/libguile/inline.h
@@ -95,6 +95,7 @@ SCM_API SCM scm_array_handle_ref (scm_t_array_handle *h, ssize_t pos);
 SCM_API void scm_array_handle_set (scm_t_array_handle *h, ssize_t pos, SCM val);
 
 SCM_API int scm_is_pair (SCM x);
+SCM_API int scm_is_string (SCM x);
 
 SCM_API int scm_get_byte_or_eof (SCM port);
 SCM_API void scm_putc (char c, SCM port);
diff --git a/libguile/strings.h b/libguile/strings.h
index d43925975..00bc22430 100644
--- a/libguile/strings.h
+++ b/libguile/strings.h
@@ -125,7 +125,6 @@ SCM_API SCM scm_c_substring_read_only (SCM str, size_t start, size_t end);
 SCM_API SCM scm_c_substring_shared (SCM str, size_t start, size_t end);
 SCM_API SCM scm_c_substring_copy (SCM str, size_t start, size_t end);
 
-SCM_API int scm_is_string (SCM x);
 SCM_API SCM scm_from_latin1_stringn (const char *str, size_t len);
 SCM_API SCM scm_from_locale_string (const char *str);
 SCM_API SCM scm_from_locale_stringn (const char *str, size_t len);