Comment by CJefferson

Ooo, let's try something functional:

    > map reverse

    No instance for (GHC.Show.Show ([[a0]] -> [[a0]]))
    arising from a use of `M1690418375.show_M1690418375'
    Possible fix:
    add an instance declaration for (GHC.Show.Show ([[a0]] -> [[a0]]))

Hmm....