| 1 | module Main where |
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| 2 | |
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| 3 | data Foo = Foo Int deriving (Eq, Show) |
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| 4 | |
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| 5 | class Proposition a where |
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| 6 | |
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| 7 | instance Proposition Foo where |
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| 8 | |
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| 9 | data (Proposition a, Show a) => F a = P a | F :/\: F |
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| 10 | -- data (Proposition a, Show a) => F a = P a | (F a) :/\: (F a) |
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| 11 | |
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| 12 | f = (P (Foo 3)) :/\: (P (Foo 5)) |
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