2014-08-29 01:20:58 +00:00
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let bool := Prop,
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2016-06-01 02:14:42 +00:00
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and := λ p q, Π c, (p → q → c) → c,
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and_intro := λ p q H1 H2 c H, H H1 H2
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2014-08-29 01:20:58 +00:00
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in and_intro :
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2016-06-01 02:14:42 +00:00
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∀ p q,
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p → q → (∀ c, (p → q → c) → c)
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2014-08-22 18:26:00 +00:00
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let1.lean:19:19: error: type mismatch at term
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2016-06-01 02:14:42 +00:00
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λ p q H1 H2 c H,
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2014-08-29 01:20:58 +00:00
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H H1 H2
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has type
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2016-06-01 02:14:42 +00:00
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∀ p q,
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p → q → (∀ c, (p → q → c) → c)
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2014-08-22 18:26:00 +00:00
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but is expected to have type
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2016-06-01 02:14:42 +00:00
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∀ p q,
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p → q → (λ p q, ∀ c, (p → q → c) → c) q p
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