intercalate -text

intercalate :: [a] -> [[a]] -> [a]
base Data.List
intercalate xs xss is equivalent to (concat (intersperse xs xss)). It inserts the list xs in between the lists in xss and concatenates the result.
intercalate :: ByteString -> [ByteString] -> ByteString
bytestring Data.ByteString, bytestring Data.ByteString.Char8, bytestring Data.ByteString.Lazy, bytestring Data.ByteString.Lazy.Char8
O(n) The intercalate function takes a ByteString and a list of ByteStrings and concatenates the list after interspersing the first argument between each element of the list.