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intOrbitInterpret
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IndisputableMonolith.Foundation.UniversalForcing.OrderRealization on GitHub at line 33.
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30 simp [intCost, h, h']
31
32/-- Interpret `LogicNat` as nonnegative integers. -/
33def intOrbitInterpret (n : LogicNat) : ℤ :=
34 (LogicNat.toNat n : ℤ)
35
36/-- Ordered integer realization with unit step. -/
37def orderRealization : LogicRealization where
38 Carrier := ℤ
39 Cost := Nat
40 zeroCost := inferInstance
41 compare := intCost
42 zero := 0
43 step := fun z => z + 1
44 Orbit := LogicNat
45 orbitZero := LogicNat.zero
46 orbitStep := LogicNat.succ
47 interpret := intOrbitInterpret
48 interpret_zero := by simp [intOrbitInterpret]
49 interpret_step := by
50 intro n
51 show ((LogicNat.toNat (LogicNat.succ n) : ℤ) = (LogicNat.toNat n : ℤ) + 1)
52 rw [LogicNat.toNat_succ]
53 norm_num
54 orbit_no_confusion := by
55 intro n h
56 exact LogicNat.zero_ne_succ n h
57 orbit_step_injective := LogicNat.succ_injective
58 orbit_induction := by
59 intro P h0 hs n
60 exact LogicNat.induction (motive := P) h0 hs n
61 orbitEquivLogicNat := Equiv.refl LogicNat
62 orbitEquiv_zero := rfl
63 orbitEquiv_step := by intro n; rfl