patch 8.1.2020: it is not easy to change the window layout
Problem: It is not easy to change the window layout.
Solution: Add win_splitmove(). (Andy Massimino, closes #4561)
diff --git a/src/proto/evalwindow.pro b/src/proto/evalwindow.pro
index c201a2e..e3faa96 100644
--- a/src/proto/evalwindow.pro
+++ b/src/proto/evalwindow.pro
@@ -19,6 +19,7 @@
void f_win_id2tabwin(typval_T *argvars, typval_T *rettv);
void f_win_id2win(typval_T *argvars, typval_T *rettv);
void f_win_screenpos(typval_T *argvars, typval_T *rettv);
+void f_win_splitmove(typval_T *argvars, typval_T *rettv);
void f_winbufnr(typval_T *argvars, typval_T *rettv);
void f_wincol(typval_T *argvars, typval_T *rettv);
void f_winheight(typval_T *argvars, typval_T *rettv);