diff --git a/src/proto/list.pro b/src/proto/list.pro
index 5a2feea..2699050 100644
--- a/src/proto/list.pro
+++ b/src/proto/list.pro
@@ -48,6 +48,7 @@
 void f_uniq(typval_T *argvars, typval_T *rettv);
 void f_filter(typval_T *argvars, typval_T *rettv);
 void f_map(typval_T *argvars, typval_T *rettv);
+void f_mapnew(typval_T *argvars, typval_T *rettv);
 void f_add(typval_T *argvars, typval_T *rettv);
 void f_count(typval_T *argvars, typval_T *rettv);
 void f_extend(typval_T *argvars, typval_T *rettv);