19 lines
506 B
Text
19 lines
506 B
Text
open tactic
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example (p q : Prop) [s₁ : decidable p] [s₂ : decidable q] : true :=
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begin
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unfreeze_local_instances,
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with_cases { cases s₁; cases s₂ },
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trace_state,
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all_goals { intros, trivial }
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end
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def split (p : Prop) {q : Prop} [decidable p] (pos : p → q) (neg : ¬ p → q) : q :=
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decidable.by_cases pos neg
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example (p q : Prop) [decidable p] [decidable q] : true :=
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begin
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with_cases { apply split p; apply split q; intros hq hp },
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trace_state,
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all_goals { intros, trivial }
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end
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