11 lines
380 B
Text
11 lines
380 B
Text
import logic data.nat
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open nat
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inductive fin : ℕ → Type :=
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zero : Π {n : ℕ}, fin (succ n),
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succ : Π {n : ℕ}, fin n → fin (succ n)
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theorem foo (n m : ℕ) (a : fin n) (b : fin m) (H : n = m) : cast (congr_arg fin H) a = b :=
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have eq : fin n = fin m, from congr_arg fin H,
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have ceq : cast eq a = b, from sorry, -- sorry implicit argument must have access to eq
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sorry
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