That’s true. However it could add a lot of overhead to loading large projects (it can take a second or two for a large project to be loaded at the moment).
I personally use IntelliJ IDEA with the Lua plugin.
The plugin is still relatively young so it doesn’t support all the lovely things that IDEA can do, like refactoring, but it is the best Lua IDE I have used to date — and one of the few that works on OSX.
Additionally it works with the community edition of IDEA, so the price is right.
Alternatively you might want to take a look at Decoda