empty -bytestring +pretty

empty :: Doc
pretty Text.PrettyPrint.HughesPJ, pretty Text.PrettyPrint
The empty document, with no height and no width. empty is the identity for <>, <+>, $$ and $+$, and anywhere in the argument list for sep, hcat, hsep, vcat, fcat etc.
isEmpty :: Doc -> Bool
pretty Text.PrettyPrint.HughesPJ, pretty Text.PrettyPrint
Returns True if the document is empty