Make NoExt uninhabited
Currently HsExtension.NoExt
is a unit type:
data NoExt = NoExt
However, it is always(?) used to fill extension constructors which generally aren't meaningful. This is awkward as you then have cases like !1265 (comment 209231) where GHC implementation is forced to deal with a constructor that should never actually occur.
It seems like NoExt
should rather be unhabited:
data NoExt
Why isn't this the case?