1 files changed, 5 insertions, 1 deletions
diff --git a/src/nvim/eval/funcs.h b/src/nvim/eval/funcs.h
index 3ad0b8282a..c6a0cb959e 100644
--- a/src/nvim/eval/funcs.h
+++ b/src/nvim/eval/funcs.h
@@ -9,12 +9,16 @@ typedef void (*FunPtr)(void);
 /// Prototype of C function that implements VimL function
 typedef void (*VimLFunc)(typval_T *args, typval_T *rvar, FunPtr data);
 
+/// Special flags for base_arg @see VimLFuncDef
+#define BASE_NONE 0          ///< Not a method (no base argument).
+#define BASE_LAST UINT8_MAX  ///< Use the last argument as the method base.
+
 /// Structure holding VimL function definition
 typedef struct fst {
   char *name;        ///< Name of the function.
   uint8_t min_argc;  ///< Minimal number of arguments.
   uint8_t max_argc;  ///< Maximal number of arguments.
-  uint8_t base_arg;  ///< Method base arg # (1-indexed), or 0 if not a method.
+  uint8_t base_arg;  ///< Method base arg # (1-indexed), BASE_NONE or BASE_LAST.
   VimLFunc func;     ///< Function implementation.
   FunPtr data;       ///< Userdata for function implementation.
 } VimLFuncDef;