lean2/tests/lean/run/tactic13.lean
Leonardo de Moura 5527955ba8 feat(frontends/lean): add 'proof-qed' notation
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
2014-07-02 19:30:48 -07:00

12 lines
No EOL
248 B
Text
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

import standard
using tactic
theorem tst (a b : Bool) (H : ¬ a ¬ b) (Hb : b) : ¬ a ∧ b :=
proof
apply and_intro,
apply not_intro,
assume Ha, or_elim H
(assume Hna, absurd Ha Hna)
(assume Hnb, absurd Hb Hnb),
assumption
qed