Text.PrettyPrint bug or doc bug

[Marcus D. Gabriel]

Hello,

The documentation for Text.PrettyPrint.HughesPJ states
that vcat is the "List version of $$", but it works as
the list version ($+$).  In the source code, this is
because

    vcat = reduceAB . foldr (above_' True) empty

instead of

    vcat = reduceAB . foldr (above_' False) empty

So either the documentation needs to be changed or
the code.  It would be nice to have both versions.

Cheers,
- Marcus