52d4189805
Now, `dsimp` fails if the goal did not change.
We can use the config object to obtain the previous behavior:
```
dsimp {fail_if_unchaged := ff}
```
See comment https://github.com/leanprover/lean/issues/1694#issuecomment-310956315
at issue #1694
23 lines
737 B
Text
23 lines
737 B
Text
@[reducible]
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def nat_has_add2 : has_add nat :=
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⟨λ x y : nat, nat.add x y⟩
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set_option pp.all true
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open tactic
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local attribute [-simp] id.def
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example (a b : nat) (H : @has_add.add nat (id (id nat.has_add)) a b = @has_add.add nat nat_has_add2 a b) : true :=
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by do
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s ← simp_lemmas.mk_default,
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get_local `H >>= infer_type >>= s^.dsimplify >>= trace,
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constructor
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example (a b : nat) (H : (λ x : nat, @has_add.add nat (id (id nat.has_add)) a b) = (λ x : nat, @has_add.add nat nat_has_add2 a x)) : true :=
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by do
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s ← simp_lemmas.mk_default,
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get_local `H >>= infer_type >>= s^.dsimplify >>= trace,
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constructor
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attribute [reducible]
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definition nat_has_add3 : nat → has_add nat :=
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λ n, has_add.mk (λ x y : nat, x + y)
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