14 lines
390 B
Text
14 lines
390 B
Text
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import standard
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using tactic
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definition basic_tac : tactic
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:= repeat (apply @and_intro | apply @not_intro | assumption)
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reset_proof_qed basic_tac -- basic_tac is automatically applied to each element of a proof-qed block
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theorem tst (a b : Bool) (H : ¬ a ∨ ¬ b) (Hb : b) : ¬ a ∧ b :=
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proof
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assume Ha, or_elim H
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(assume Hna, absurd Ha Hna)
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(assume Hnb, absurd Hb Hnb)
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qed
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