diff --git a/lualib/sprotoparser.lua b/lualib/sprotoparser.lua
index 7b0b04e2..03524ac0 100644
--- a/lualib/sprotoparser.lua
+++ b/lualib/sprotoparser.lua
@@ -81,7 +81,7 @@ end
 
 local typedef = P {
 	"ALL",
-	FIELD = namedpat("field", (name * blanks * tag * blank0 * ":" * blank0 * (C"*")^0 * typename * mainkey^0)),
+	FIELD = namedpat("field", (name * blanks * tag * blank0 * ":" * blank0 * (C"*")^-1 * typename * mainkey^0)),
 	STRUCT = P"{" * multipat(V"FIELD" + V"TYPE") * P"}",
 	TYPE = namedpat("type", P"." * name * blank0 * V"STRUCT" ),
 	SUBPROTO = Ct((C"request" + C"response") * blanks * (typename + V"STRUCT")),