content: on run
  
    concat([["alpha", "beta", "gamma"], ¬
      ["delta", "epsilon", "zeta"], ¬
      ["eta", "theta", "iota"]])
  
  end run
  
  
  -- concat :: [[a]] -> [a]
  on concat(xxs)
    set lst to {}
    repeat with xs in xxs
      set lst to lst & xs
    end repeat
    return lst
  end concat
  