-- Returns the function used by the given SigDef, if any
usedHsFunc :: SigDef -> Maybe HsFunction
usedHsFunc (FApp hsfunc _ _) = Just hsfunc
-- Returns the function used by the given SigDef, if any
usedHsFunc :: SigDef -> Maybe HsFunction
usedHsFunc (FApp hsfunc _ _) = Just hsfunc