40 lines
691 B
Text
40 lines
691 B
Text
import Lean
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open Lean
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open Lean.Meta
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def tst (declName : Name) : MetaM Unit := do
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IO.println (← getUnfoldEqnFor? declName)
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mutual
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def g (i j : Nat) : Nat :=
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if i < 5 then 0 else
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match j with
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| Nat.zero => 1
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| Nat.succ j => h i j
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termination_by (i + j, 0)
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decreasing_by
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simp_wf
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· apply Prod.Lex.left
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apply Nat.lt_succ_self
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def h (i j : Nat) : Nat :=
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match j with
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| 0 => g i 0
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| Nat.succ j => g i j
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termination_by (i + j, 1)
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decreasing_by
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all_goals simp_wf
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· apply Prod.Lex.right
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decide
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· apply Prod.Lex.left
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apply Nat.lt_succ_self
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end
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#eval tst ``g
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#check g.eq_1
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#check g.eq_2
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#check g.def
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#eval tst ``h
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#check h.eq_1
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#check h.eq_2
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#check h.def
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