What top-level names are “allocated”?

Hi! When uploading a new version of grapefruit-frp yesterday, I got the following warning from cabal-install:

 Exposed modules use unallocated top-level names: FRP

This made me wonder which top-level names are actually “allocated”. I tried to find this out from the Cabal sources, but the GitHub search functionality revealed no occurrences of the word “unallocated”. Regarding my concrete case, I think it would be good to change “FRP” to “Reactive”, which is what Reactive Banana is using, for example. However, is “Reactive” an “allocated” top-level name? All the best, Wolfgang