diff --git a/src/eval.c b/src/eval.c
index 6d666e6..3b789da 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -1272,6 +1272,7 @@
 	switch (tv1->v_type)
 	{
 	    case VAR_UNKNOWN:
+	    case VAR_ANY:
 	    case VAR_VOID:
 	    case VAR_DICT:
 	    case VAR_FUNC:
@@ -2967,6 +2968,7 @@
 		emsg(_("E909: Cannot index a special variable"));
 	    return FAIL;
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    if (evaluate)
 		return FAIL;
@@ -3073,6 +3075,7 @@
 	switch (rettv->v_type)
 	{
 	    case VAR_UNKNOWN:
+	    case VAR_ANY:
 	    case VAR_VOID:
 	    case VAR_FUNC:
 	    case VAR_PARTIAL:
@@ -3668,7 +3671,7 @@
 }
 
 /*
- * Return the function name of the partial.
+ * Return the function name of partial "pt".
  */
     char_u *
 partial_name(partial_T *pt)
@@ -3856,6 +3859,7 @@
 	    return tv1->vval.v_string == tv2->vval.v_string;
 
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    break;
     }
@@ -4570,6 +4574,7 @@
 
 	case VAR_NUMBER:
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    *tofree = NULL;
 	    r = tv_get_string_buf(tv, numbuf);
@@ -5422,6 +5427,7 @@
 #endif
 	    case VAR_NUMBER:
 	    case VAR_FLOAT:
+	    case VAR_ANY:
 	    case VAR_UNKNOWN:
 	    case VAR_VOID:
 	    case VAR_BOOL:
@@ -5486,6 +5492,7 @@
 		varp->vval.v_channel = NULL;
 #endif
 	    case VAR_UNKNOWN:
+	    case VAR_ANY:
 	    case VAR_VOID:
 		break;
 	}
@@ -5565,6 +5572,7 @@
 	    emsg(_("E974: Using a Blob as a Number"));
 	    break;
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    internal_error_no_abort("tv_get_number(UNKNOWN)");
 	    break;
@@ -5619,6 +5627,7 @@
 	    emsg(_("E975: Using a Blob as a Float"));
 	    break;
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    internal_error_no_abort("tv_get_float(UNKNOWN)");
 	    break;
@@ -5742,6 +5751,7 @@
 #endif
 	    break;
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    emsg(_(e_inval_string));
 	    break;
@@ -5891,6 +5901,7 @@
 	    }
 	    break;
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    internal_error_no_abort("copy_tv(UNKNOWN)");
 	    break;
@@ -5970,6 +5981,7 @@
 		ret = FAIL;
 	    break;
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    internal_error_no_abort("item_copy(UNKNOWN)");
 	    ret = FAIL;
diff --git a/src/evalfunc.c b/src/evalfunc.c
index 5a5daaa..3b8b319 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -2042,6 +2042,7 @@
 	    break;
 #endif
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    internal_error_no_abort("f_empty(UNKNOWN)");
 	    n = TRUE;
@@ -5217,6 +5218,7 @@
 	    rettv->vval.v_number = dict_len(argvars[0].vval.v_dict);
 	    break;
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	case VAR_BOOL:
 	case VAR_SPECIAL:
@@ -8805,6 +8807,7 @@
 	case VAR_CHANNEL: n = VAR_TYPE_CHANNEL; break;
 	case VAR_BLOB:    n = VAR_TYPE_BLOB; break;
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	     internal_error_no_abort("f_type(UNKNOWN)");
 	     n = -1;
diff --git a/src/evalvars.c b/src/evalvars.c
index d434d58..6b9c270 100644
--- a/src/evalvars.c
+++ b/src/evalvars.c
@@ -1668,6 +1668,7 @@
     switch (tv->v_type)
     {
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	case VAR_NUMBER:
 	case VAR_BOOL:
diff --git a/src/globals.h b/src/globals.h
index 1a6a0d8..6f594e9 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -379,7 +379,8 @@
 
 
 // Commonly used types.
-EXTERN type_T t_any INIT6(VAR_UNKNOWN, 0, 0, 0, NULL, NULL);
+EXTERN type_T t_unknown INIT6(VAR_UNKNOWN, 0, 0, 0, NULL, NULL);
+EXTERN type_T t_any INIT6(VAR_ANY, 0, 0, 0, NULL, NULL);
 EXTERN type_T t_void INIT6(VAR_VOID, 0, 0, 0, NULL, NULL);
 EXTERN type_T t_bool INIT6(VAR_BOOL, 0, 0, 0, NULL, NULL);
 EXTERN type_T t_special INIT6(VAR_SPECIAL, 0, 0, 0, NULL, NULL);
@@ -390,6 +391,7 @@
 EXTERN type_T t_job INIT6(VAR_JOB, 0, 0, 0, NULL, NULL);
 EXTERN type_T t_channel INIT6(VAR_CHANNEL, 0, 0, 0, NULL, NULL);
 
+EXTERN type_T t_func_unknown INIT6(VAR_FUNC, -1, 0, 0, &t_unknown, NULL);
 EXTERN type_T t_func_void INIT6(VAR_FUNC, -1, 0, 0, &t_void, NULL);
 EXTERN type_T t_func_any INIT6(VAR_FUNC, -1, 0, 0, &t_any, NULL);
 EXTERN type_T t_func_number INIT6(VAR_FUNC, -1, 0, 0, &t_number, NULL);
@@ -401,8 +403,8 @@
 
 EXTERN type_T t_list_any INIT6(VAR_LIST, 0, 0, 0, &t_any, NULL);
 EXTERN type_T t_dict_any INIT6(VAR_DICT, 0, 0, 0, &t_any, NULL);
-EXTERN type_T t_list_empty INIT6(VAR_LIST, 0, 0, 0, &t_void, NULL);
-EXTERN type_T t_dict_empty INIT6(VAR_DICT, 0, 0, 0, &t_void, NULL);
+EXTERN type_T t_list_empty INIT6(VAR_LIST, 0, 0, 0, &t_unknown, NULL);
+EXTERN type_T t_dict_empty INIT6(VAR_DICT, 0, 0, 0, &t_unknown, NULL);
 
 EXTERN type_T t_list_bool INIT6(VAR_LIST, 0, 0, 0, &t_bool, NULL);
 EXTERN type_T t_list_number INIT6(VAR_LIST, 0, 0, 0, &t_number, NULL);
diff --git a/src/if_py_both.h b/src/if_py_both.h
index 0d70de2..77ec4a9 100644
--- a/src/if_py_both.h
+++ b/src/if_py_both.h
@@ -6390,6 +6390,7 @@
 		(char*) tv->vval.v_blob->bv_ga.ga_data,
 		(Py_ssize_t) tv->vval.v_blob->bv_ga.ga_len);
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	case VAR_CHANNEL:
 	case VAR_JOB:
diff --git a/src/json.c b/src/json.c
index f4a03e6..c1c6e85 100644
--- a/src/json.c
+++ b/src/json.c
@@ -351,6 +351,7 @@
 	    break;
 #endif
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    internal_error_no_abort("json_encode_item()");
 	    return FAIL;
diff --git a/src/structs.h b/src/structs.h
index 4a51281..46e2701 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -1321,8 +1321,9 @@
 
 typedef enum
 {
-    VAR_UNKNOWN = 0,	// not set, also used for "any" type
-    VAR_VOID,		// no value
+    VAR_UNKNOWN = 0,	// not set, any type or "void" allowed
+    VAR_ANY,		// used for "any" type
+    VAR_VOID,		// no value (function not returning anything)
     VAR_BOOL,		// "v_number" is used: VVAL_TRUE or VVAL_FALSE
     VAR_SPECIAL,	// "v_number" is used: VVAL_NULL or VVAL_NONE
     VAR_NUMBER,		// "v_number" is used
diff --git a/src/testdir/test_vim9_func.vim b/src/testdir/test_vim9_func.vim
index 6f61254..c122168 100644
--- a/src/testdir/test_vim9_func.vim
+++ b/src/testdir/test_vim9_func.vim
@@ -386,6 +386,27 @@
   Ref1 = FuncNoArgNoRet
   Ref1()
   assert_equal(11, funcResult)
+
+  let Ref2: func
+  funcResult = 0
+  Ref2 = FuncNoArgNoRet
+  Ref2()
+  assert_equal(11, funcResult)
+
+  funcResult = 0
+  Ref2 = FuncOneArgNoRet
+  Ref2(12)
+  assert_equal(12, funcResult)
+
+  funcResult = 0
+  Ref2 = FuncNoArgRetNumber
+  assert_equal(1234, Ref2())
+  assert_equal(22, funcResult)
+
+  funcResult = 0
+  Ref2 = FuncOneArgRetNumber
+  assert_equal(13, Ref2(13))
+  assert_equal(13, funcResult)
 enddef
 
 def Test_func_type_fails()
diff --git a/src/testing.c b/src/testing.c
index 81e1762..35c2683 100644
--- a/src/testing.c
+++ b/src/testing.c
@@ -764,6 +764,7 @@
     switch (argvars[0].v_type)
     {
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	case VAR_NUMBER:
 	case VAR_BOOL:
diff --git a/src/version.c b/src/version.c
index fb73614..4c07cd2 100644
--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    517,
+/**/
     516,
 /**/
     515,
diff --git a/src/vim9compile.c b/src/vim9compile.c
index 526f25b..98936dd 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -249,9 +249,10 @@
     type_T *type;
 
     // recognize commonly used types
-    if (member_type->tt_type == VAR_UNKNOWN)
+    if (member_type->tt_type == VAR_ANY)
 	return &t_list_any;
-    if (member_type->tt_type == VAR_VOID)
+    if (member_type->tt_type == VAR_VOID
+	    || member_type->tt_type == VAR_UNKNOWN)
 	return &t_list_empty;
     if (member_type->tt_type == VAR_BOOL)
 	return &t_list_bool;
@@ -277,9 +278,10 @@
     type_T *type;
 
     // recognize commonly used types
-    if (member_type->tt_type == VAR_UNKNOWN)
+    if (member_type->tt_type == VAR_ANY)
 	return &t_dict_any;
-    if (member_type->tt_type == VAR_VOID)
+    if (member_type->tt_type == VAR_VOID
+	    || member_type->tt_type == VAR_UNKNOWN)
 	return &t_dict_empty;
     if (member_type->tt_type == VAR_BOOL)
 	return &t_dict_bool;
@@ -482,9 +484,9 @@
     static int
 check_number_or_float(vartype_T type1, vartype_T type2, char_u *op)
 {
-    if (!((type1 == VAR_NUMBER || type1 == VAR_FLOAT || type1 == VAR_UNKNOWN)
+    if (!((type1 == VAR_NUMBER || type1 == VAR_FLOAT || type1 == VAR_ANY)
 	    && (type2 == VAR_NUMBER || type2 == VAR_FLOAT
-						     || type2 == VAR_UNKNOWN)))
+							 || type2 == VAR_ANY)))
     {
 	if (*op == '+')
 	    emsg(_("E1035: wrong argument type for +"));
@@ -515,7 +517,7 @@
     // checking.
     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2];
     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1];
-    vartype = VAR_UNKNOWN;
+    vartype = VAR_ANY;
     if (type1->tt_type == type2->tt_type
 	    && (type1->tt_type == VAR_NUMBER
 		|| type1->tt_type == VAR_LIST
@@ -528,8 +530,8 @@
     switch (*op)
     {
 	case '+': if (vartype != VAR_LIST && vartype != VAR_BLOB
-			  && type1->tt_type != VAR_UNKNOWN
-			  && type2->tt_type != VAR_UNKNOWN
+			  && type1->tt_type != VAR_ANY
+			  && type2->tt_type != VAR_ANY
 			  && check_number_or_float(
 				   type1->tt_type, type2->tt_type, op) == FAIL)
 		      return FAIL;
@@ -563,9 +565,9 @@
 				 ? EXPR_MULT : *op == '/'? EXPR_DIV : EXPR_SUB;
 		  break;
 
-	case '%': if ((type1->tt_type != VAR_UNKNOWN
+	case '%': if ((type1->tt_type != VAR_ANY
 					       && type1->tt_type != VAR_NUMBER)
-			  || (type2->tt_type != VAR_UNKNOWN
+			  || (type2->tt_type != VAR_ANY
 					      && type2->tt_type != VAR_NUMBER))
 		  {
 		      emsg(_("E1035: % requires number arguments"));
@@ -579,7 +581,7 @@
     }
 
     // correct type of result
-    if (vartype == VAR_UNKNOWN)
+    if (vartype == VAR_ANY)
     {
 	type_T *type = &t_any;
 
@@ -614,6 +616,11 @@
     // checking.
     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2]->tt_type;
     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1]->tt_type;
+    if (type1 == VAR_UNKNOWN)
+	type1 = VAR_ANY;
+    if (type2 == VAR_UNKNOWN)
+	type2 = VAR_ANY;
+
     if (type1 == type2)
     {
 	switch (type1)
@@ -631,7 +638,7 @@
 	    default: isntype = ISN_COMPAREANY; break;
 	}
     }
-    else if (type1 == VAR_UNKNOWN || type2 == VAR_UNKNOWN
+    else if (type1 == VAR_ANY || type2 == VAR_ANY
 	    || ((type1 == VAR_NUMBER || type1 == VAR_FLOAT)
 	      && (type2 == VAR_NUMBER || type2 ==VAR_FLOAT)))
 	isntype = ISN_COMPAREANY;
@@ -1723,8 +1730,9 @@
 	return FALSE;
     switch (type1->tt_type)
     {
-	case VAR_VOID:
 	case VAR_UNKNOWN:
+	case VAR_ANY:
+	case VAR_VOID:
 	case VAR_SPECIAL:
 	case VAR_BOOL:
 	case VAR_NUMBER:
@@ -1785,6 +1793,7 @@
     switch (type)
     {
 	case VAR_UNKNOWN: break;
+	case VAR_ANY: return "any";
 	case VAR_VOID: return "void";
 	case VAR_SPECIAL: return "special";
 	case VAR_BOOL: return "bool";
@@ -1799,7 +1808,7 @@
 	case VAR_FUNC: return "func";
 	case VAR_PARTIAL: return "partial";
     }
-    return "any";
+    return "unknown";
 }
 
 /*
@@ -2396,7 +2405,7 @@
 {
     int ret = OK;
 
-    if (expected->tt_type != VAR_UNKNOWN)
+    if (expected->tt_type != VAR_UNKNOWN && expected->tt_type != VAR_ANY)
     {
 	if (expected->tt_type != actual->tt_type)
 	{
@@ -2406,13 +2415,14 @@
 	}
 	if (expected->tt_type == VAR_DICT || expected->tt_type == VAR_LIST)
 	{
-	    // void is used for an empty list or dict
-	    if (actual->tt_member != &t_void)
+	    // "unknown" is used for an empty list or dict
+	    if (actual->tt_member != &t_unknown)
 		ret = check_type(expected->tt_member, actual->tt_member, FALSE);
 	}
 	else if (expected->tt_type == VAR_FUNC)
 	{
-	    if (expected->tt_member != &t_any)
+	    if (expected->tt_member != &t_any
+					  && expected->tt_member != &t_unknown)
 		ret = check_type(expected->tt_member, actual->tt_member, FALSE);
 	    if (ret == OK && expected->tt_argcount != -1
 		    && (actual->tt_argcount < expected->tt_min_argcount
@@ -2436,7 +2446,7 @@
 {
     if (check_type(expected, actual, FALSE))
 	return OK;
-    if (actual->tt_type != VAR_UNKNOWN)
+    if (actual->tt_type != VAR_ANY && actual->tt_type != VAR_UNKNOWN)
     {
 	type_mismatch(expected, actual);
 	return FAIL;
@@ -3642,7 +3652,8 @@
     {
 	// "set_return_type" cannot be TRUE, only used for a lambda which
 	// always has an argument.
-	if (cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_VOID)
+	if (cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_VOID
+		&& cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_UNKNOWN)
 	{
 	    emsg(_("E1003: Missing return value"));
 	    return NULL;
@@ -3936,7 +3947,7 @@
     }
 
     if (oplen == 3 && !heredoc && dest != dest_global
-	    && type->tt_type != VAR_STRING && type->tt_type != VAR_UNKNOWN)
+		    && type->tt_type != VAR_STRING && type->tt_type != VAR_ANY)
     {
 	emsg(_("E1019: Can only concatenate to string"));
 	goto theend;
@@ -4115,6 +4126,7 @@
 		break;
 	    case VAR_NUMBER:
 	    case VAR_UNKNOWN:
+	    case VAR_ANY:
 	    case VAR_VOID:
 	    case VAR_SPECIAL:  // cannot happen
 		generate_PUSHNR(cctx, 0);
@@ -4903,7 +4915,7 @@
 	drop_scope(cctx);
 	return NULL;
     }
-    if (vartype->tt_member->tt_type != VAR_UNKNOWN)
+    if (vartype->tt_member->tt_type != VAR_ANY)
     {
 	lvar_T *lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + var_idx;
 
diff --git a/src/vim9execute.c b/src/vim9execute.c
index 237b024..b7ec979 100644
--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -2239,6 +2239,7 @@
 	case VAR_BLOB:
 	    return tv->vval.v_blob != NULL && tv->vval.v_blob->bv_ga.ga_len > 0;
 	case VAR_UNKNOWN:
+	case VAR_ANY:
 	case VAR_VOID:
 	    break;
     }
diff --git a/src/viminfo.c b/src/viminfo.c
index c1339f0..b014d7f 100644
--- a/src/viminfo.c
+++ b/src/viminfo.c
@@ -1344,6 +1344,7 @@
 		    case VAR_SPECIAL: s = "XPL"; break;
 
 		    case VAR_UNKNOWN:
+		    case VAR_ANY:
 		    case VAR_VOID:
 		    case VAR_FUNC:
 		    case VAR_PARTIAL: