Lua uses self, not this

There is no 'this' in lua. There is however 'self' a predefined parameter when using colon syntax for calling a function.

http://www.lua.org/pil/16.html

lib/ace/mode/lua_highlight_rules.js

@@ -83,7 +83,7 @@ var LuaHighlightRules = function() {
         "constant.library": stdLibaries,
         "constant.language": builtinConstants,
         "invalid.illegal": futureReserved,
-        "variable.language": "this"
+        "variable.language": "self"
     }, "identifier");
 
     var decimalInteger = "(?:(?:[1-9]\\d*)|(?:0))";