[1 of 1] Compiling Data.Sign        ( src/Data/Sign.hs, dist/build/Data/Sign.o )

src/Data/Sign.hs:128:10:
    Overlapping instances for L.MeetSemiLattice (Set Sign)
      arising from the superclasses of an instance declaration
    Matching instances:
      instance Ord a => L.MeetSemiLattice (Set a)
        -- Defined in ‘Algebra.Lattice’
      instance L.MeetSemiLattice (Set Sign)
        -- Defined at src/Data/Sign.hs:123:10
    In the instance declaration for
      ‘L.BoundedMeetSemiLattice (Set Sign)’

src/Data/Sign.hs:131:10:
    Overlapping instances for L.Lattice (Set Sign)
      arising from the superclasses of an instance declaration
    Matching instances:
      instance Ord a => L.Lattice (Set a) -- Defined in ‘Algebra.Lattice’
      instance L.Lattice (Set Sign) -- Defined at src/Data/Sign.hs:126:10
    In the instance declaration for ‘L.BoundedLattice (Set Sign)’