--- a/src/variables.h
+++ b/src/variables.h
@@ -109,6 +109,11 @@
 set_internal_variable (std::string& var, const octave_value_list& args,
                        int nargout, const char *nm, bool empty_ok = true);
 
+extern OCTINTERP_API octave_value
+set_internal_variable (int& var, const octave_value_list& args,
+                       int nargout, const char *nm, const char **choices,
+                       int nchoices);
+
 #define SET_INTERNAL_VARIABLE(NM) \
   set_internal_variable (V ## NM, args, nargout, #NM)
 
@@ -118,6 +123,11 @@
 #define SET_INTERNAL_VARIABLE_WITH_LIMITS(NM, MINVAL, MAXVAL) \
   set_internal_variable (V ## NM, args, nargout, #NM, MINVAL, MAXVAL)
 
+// in the following, CHOICES must be a static C string array.
+#define SET_INTERNAL_VARIABLE_CHOICES(NM, CHOICES) \
+  set_internal_variable (V ## NM, args, nargout, #NM, CHOICES, \
+                         sizeof (CHOICES) / sizeof (const char *))
+
 extern OCTINTERP_API std::string builtin_string_variable (const std::string&);
 extern OCTINTERP_API int builtin_real_scalar_variable (const std::string&, double&);
 extern OCTINTERP_API octave_value builtin_any_variable (const std::string&);