ptext SLIT("which is mentioned in the environment")
| otherwise = ptext SLIT("It is mentioned in the environment")
+ vcat_first :: Int -> [SDoc] -> SDoc
vcat_first n [] = empty
vcat_first 0 (x:xs) = text "...others omitted..."
vcat_first n (x:xs) = x $$ vcat_first (n-1) xs