unwords package:Cabal-syntax

unwords :: [String] -> String
Cabal-syntax Distribution.Compat.Prelude
unwords joins words with separating spaces (U+0020 SPACE). 
>>> unwords ["Lorem", "ipsum", "dolor"]
"Lorem ipsum dolor"
unwords is neither left nor right inverse of words: 
>>> words (unwords [" "])
[]

>>> unwords (words "foo\nbar")
"foo bar"