4bacd70b3f
This was suggested by Scott Morrison to be able to help projects adjust to `Nat` having built-in custom eliminators.
48 lines
667 B
Text
48 lines
667 B
Text
/-!
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# Tests for the custom eliminators feature for `induction` and `cases`
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-/
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/-!
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Test the built-in custom `Nat` eliminator.
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-/
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/--
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error: unsolved goals
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case zero
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P : Nat → Prop
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⊢ P 0
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case succ
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P : Nat → Prop
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n✝ : Nat
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a✝ : P n✝
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⊢ P (n✝ + 1)
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-/
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#guard_msgs in
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example (P : Nat → Prop) : P n := by
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induction n
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done
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/-!
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Turn off the built-in custom `Nat` eliminator.
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-/
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section
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set_option tactic.customEliminators false
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/--
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error: unsolved goals
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case zero
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P : Nat → Prop
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⊢ P Nat.zero
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case succ
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P : Nat → Prop
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n✝ : Nat
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n_ih✝ : P n✝
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⊢ P n✝.succ
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-/
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#guard_msgs in
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example (P : Nat → Prop) : P n := by
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induction n
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done
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end
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