20 lines
489 B
Text
20 lines
489 B
Text
-- HoTT
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import homotopy.circle
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open circle eq int pi
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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 arrow_pathover_left, intro b, apply concato_eq, apply pathover_eq_r,
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xrewrite [power_con, transport_code_loop]},
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end
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