2185ee7e95
The new let tactic is semantically equivalent to let terms, while `note` preserves its old opaque behavior.
21 lines
350 B
Text
21 lines
350 B
Text
import data.nat
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open algebra
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example (a b : Prop) : a → b → a ∧ b :=
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begin
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intro Ha, intro Hb,
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let Ha' := Ha,
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let Hb' := Hb,
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let aux := and.intro Ha Hb,
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exact aux
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end
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open nat
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example (a b : nat) : a > 0 → b > 0 → a + b + 0 > 0 :=
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begin
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intro agt0, intro bgt0,
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let H := add_pos agt0 bgt0,
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change a + b > 0,
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exact H
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end
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