Data.List.join

[Henning Thielemann]

On Sat, 21 Oct 2006, Josef Svenningsson wrote:

> I'd like to propose to include the following function in Data.List:
> join :: [a] -> [[a]] -> [a]
> join x xs = concat (intersperse x xs)

analogously to
  concatMap = concat . map
we might prefer
  concatIntersperse = concat . intersperse