14 lines
392 B
Text
14 lines
392 B
Text
import logic
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using tactic
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definition basic_tac : tactic
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:= repeat [apply @and_intro | assumption]
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set_begin_end_tactic basic_tac -- basic_tac is automatically applied to each element of a proof-qed block
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theorem tst (a b : Prop) (H : ¬ a ∨ ¬ b) (Hb : b) : ¬ a ∧ b :=
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begin
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assume Ha, or_elim H
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(assume Hna, @absurd _ false Ha Hna)
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(assume Hnb, @absurd _ false Hb Hnb)
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end
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