Slot Types

Is there a list or ducumentation available anywhere that lists all of the available slot types in the game? Or an easy way that I can extract the information with studio?

I'm working on a fence and have noticed there is an object flag for "requires fence slot" in most objects that I have never seen used which made me wonder if a fence slot actually exists at all. If it did, I was thinking of trying to find a way to add it to the posts so that decorative pieces could be snapped to the fence without needing to use cheats.

I have also thought about attempting to add regular deco slots but then I would like to avoid the possibilities of Sims randomly leaving their empty glasses and plates on empty fence posts.

I realise that neither of these options may actually be viable I but wanted to try and equip myself with the info before I went any further.