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tel/gist:9070be588f9cb159ee14

Last active August 29, 2015 14:02
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gistfile1.txt
instance Monoid Bool where
mempty = True
x <> y = x == y
[ mempty <> x == x ]
True <> True == True
True <> False == False
[ x <> mempty == x ]
-- dispatched by symmetry of (==)
[ (x <> y) <> z == x <> (y <> z) ]
x y z x <> y y <> z (x <> y) <> z x <> (y <> z)
T T T T T T T
T T F T F F F
T F T F F F F
T F F F T T T
F T T F T F F
F T F F F T T
F F T T F T T
F F F T T F F
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