e4f2c39ab2
These tests came out of #2981 and #2982; let’s have them in master even if the changes there will not happen right away.
59 lines
1.8 KiB
Text
59 lines
1.8 KiB
Text
/-!
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If the recursive call is passed to the `case` tactic, it
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gets duplicate fairly often, and into different contexts
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(see below)
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So let us construct proofs that depend on that context,
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to check that the proofs are not confused.
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A work-around is
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```
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let r := foo n
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cases r
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```
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-/
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-- set_option trace.Elab.definition.wf true
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def foo : (n : Nat) → ∃ m, m > n
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| 0 => ⟨1, Nat.zero_lt_one⟩
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| n+1 => by
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cases foo n
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· case _ m hm => exact ⟨m+1, Nat.succ_lt_succ hm⟩
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decreasing_by
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-- trace_state
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solve
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| have this_is_in_the_context : ∃ m, m > n := by assumption
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cases this_is_in_the_context
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exact Nat.lt_succ_self _
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| exact Nat.lt_succ_self _
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/-
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[Elab.definition.wf] replaceRecApps:
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match n with
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| 0 => Exists.intro 1 Nat.zero_lt_one
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| Nat.succ n =>
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Exists.casesOn (motive := fun t => foo n = t → ∃ m, m > n + 1) (foo n)
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(fun w h h_1 => Exists.intro (w + 1) (Nat.succ_lt_succ h)) (Eq.refl (foo n))
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-/
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/-
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Contexts
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n: Nat
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x✝: ∀ (y : Nat), (invImage (fun a => sizeOf a) instWellFoundedRelation).1 y (Nat.succ n) → ∃ m, m > y
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t✝: ∃ m, m > n
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⊢ (invImage (fun a => sizeOf a) instWellFoundedRelation).1 n (Nat.succ n)
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n: Nat
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x✝: ∀ (y : Nat), (invImage (fun a => sizeOf a) instWellFoundedRelation).1 y (Nat.succ n) → ∃ m, m > y
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⊢ (invImage (fun a => sizeOf a) instWellFoundedRelation).1 n (Nat.succ n)
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n: Nat
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x✝: ∀ (y : Nat), (invImage (fun a => sizeOf a) instWellFoundedRelation).1 y (Nat.succ n) → ∃ m, m > y
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w✝: Nat
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h✝: w✝ > n
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⊢ (invImage (fun a => sizeOf a) instWellFoundedRelation).1 n (Nat.succ n)
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n: Nat
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x✝: ∀ (y : Nat), (invImage (fun a => sizeOf a) instWellFoundedRelation).1 y (Nat.succ n) → ∃ m, m > y
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⊢ (invImage (fun a => sizeOf a) instWellFoundedRelation).1 n (Nat.succ n)
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-/
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