20 lines
467 B
Text
20 lines
467 B
Text
import logic
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open tactic
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inductive inh [class] (A : Type) : Type :=
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intro : A -> inh A
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theorem inh_bool [instance] : inh Prop
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:= inh.intro true
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set_option trace.class_instances true
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theorem inh_fun [instance] {A B : Type} [H : inh B] : inh (A → B)
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:= inh.rec (λ b, inh.intro (λ a : A, b)) H
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theorem tst {A B : Type} (H : inh B) : inh (A → B → B)
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theorem T1 {A : Type} (a : A) : inh A :=
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by repeat (apply @inh.intro | eassumption)
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theorem T2 : inh Prop
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