21 lines
497 B
Text
21 lines
497 B
Text
-- HoTT
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import hit.circle
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open circle eq int
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attribute circle.rec circle.elim [recursor 4]
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protected definition my_code (x : circle) : Type₀ :=
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begin
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induction x,
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{ exact ℤ},
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{ apply ua, apply equiv_succ}
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end
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protected definition my_decode {x : circle} : my_code x → base = x :=
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begin
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induction x,
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{ exact power loop},
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{ apply eq_of_homotopy, intro a,
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refine !arrow.arrow_transport ⬝ !transport_eq_r ⬝ _,
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rewrite [transport_code_loop_inv,power_con,succ_pred]}
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end
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