1695b940b1
This PR ensures `simp` does not "simplify" instances by default. The old behavior can be retrieved by using `simp +instances`. This PR is similar to #12195, but for `dsimp`. The backward compatibility flag for `dsimp` also deactivates this new feature. ``` set_option backward.dsimp.instances true ``` Applying `simp` (and `dsimp`) to instances creates non-standard instances, and this creates all sorts of problems in Mathlib. --------- Co-authored-by: Henrik Böving <hargonix@gmail.com> Co-authored-by: Sebastian Graf <sgraf1337@gmail.com> Co-authored-by: Kim Morrison <kim@tqft.net>
62 lines
1.2 KiB
Text
62 lines
1.2 KiB
Text
import Lean
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set_option warn.sorry false
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def f [Add α] (a : α) := a + a
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abbrev id' (a : α) := a
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abbrev addNat : Add Nat := ⟨Nat.add⟩
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set_option pp.explicit true
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/--
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trace: a b : Nat
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⊢ @Eq Nat (@f Nat (@id' (Add Nat) addNat) a) b
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---
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trace: a b : Nat
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⊢ @Eq Nat (@f Nat addNat a) b
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-/
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#guard_msgs in
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example : @f _ (id' addNat) a = id b := by
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dsimp [id']
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trace_state -- `id'` was not unfolded because it is part of an instance
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dsimp +instances [id']
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trace_state
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sorry
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/--
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trace: a b : Nat
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⊢ @Eq Nat (@f Nat addNat a) b
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-/
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#guard_msgs in
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set_option backward.dsimp.instances true in
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example : @f _ (id' addNat) a = id b := by
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dsimp [id']
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trace_state
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sorry
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set_option linter.unusedSimpArgs false
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/--
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trace: a b : Nat
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⊢ @Eq Nat (@f Nat (@id' (Add Nat) addNat) a) b
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---
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trace: a b : Nat
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⊢ @Eq Nat (@f Nat addNat a) b
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-/
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#guard_msgs in
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example : @f _ (id' addNat) a = id b := by
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simp [id']
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trace_state -- `id'` was not unfolded because it is part of an instance
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simp +instances [id']
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trace_state
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sorry
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/--
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trace: a b : Nat
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⊢ @Eq Nat (@f Nat addNat a) b
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-/
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#guard_msgs in
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set_option backward.dsimp.instances true in
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example : @f _ (id' addNat) a = id b := by
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simp [id']
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trace_state
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sorry
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