[Merged by Bors] - refactor: induction₂_symm: Be more explicit in the case variables #11023
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and in `setToL1_mono_left`, instantiate the induction theorem explicitly. In leanprover/lean4#3505 I am fixing a big where `induction` will assume the wrong number of parameters for a case when there are let-bindings in the type involved. As part of this I am no longer reducing definitions when looking for `forall`s; this is arguably more predictable and more likely what the user wants. There are two breakages in mathlib due to this, and the fix can already be applied now.
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…rs (#3505) Else the `case` will now allow introducing all necessary variables. Induction principles with `let` in the types of the cases will be more common with #3432. This implementation no longer reduces the type as it goes, but really only counts manifest foralls and lets. I find this more sensible and predictable: If you have ``` theorem induction₂_symm {P : EReal → EReal → Prop} (symm : Symmetric P) … ``` then previously, writing ``` case symm => ``` would actually bring a fresh `x` and `y` and variable `h : P x y` into scope and produce a goal of `P y x`, because `Symmetric P` happens to be ``` def Symmetric := ∀ ⦃x y⦄, x ≺ y → y ≺ x ``` After this change, after `case symm =>` will leave `Symmetric P` as the goal. This gives more control to the author of the induction hypothesis about the actual goal of the cases. This shows up in mathlib in two places; fixes in leanprover-community/mathlib4#11023. I consider these improvements.
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and in `setToL1_mono_left`, instantiate the induction theorem explicitly. In leanprover/lean4#3505 I am fixing a big where `induction` will assume the wrong number of parameters for a case when there are let-bindings in the type involved. As part of this I am no longer reducing definitions when looking for `forall`s; this is arguably more predictable and more likely what the user wants. There are two breakages in mathlib due to this, and the fix can already be applied now. (cherry picked from commit #11023, needed for nightly 2024-02-29)
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…1023) and in `setToL1_mono_left`, instantiate the induction theorem explicitly. In leanprover/lean4#3505 I am fixing a big where `induction` will assume the wrong number of parameters for a case when there are let-bindings in the type involved. As part of this I am no longer reducing definitions when looking for `forall`s; this is arguably more predictable and more likely what the user wants. There are two breakages in mathlib due to this, and the fix can already be applied now.
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…1023) and in `setToL1_mono_left`, instantiate the induction theorem explicitly. In leanprover/lean4#3505 I am fixing a big where `induction` will assume the wrong number of parameters for a case when there are let-bindings in the type involved. As part of this I am no longer reducing definitions when looking for `forall`s; this is arguably more predictable and more likely what the user wants. There are two breakages in mathlib due to this, and the fix can already be applied now.
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…1023) and in `setToL1_mono_left`, instantiate the induction theorem explicitly. In leanprover/lean4#3505 I am fixing a big where `induction` will assume the wrong number of parameters for a case when there are let-bindings in the type involved. As part of this I am no longer reducing definitions when looking for `forall`s; this is arguably more predictable and more likely what the user wants. There are two breakages in mathlib due to this, and the fix can already be applied now.
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…1023) and in `setToL1_mono_left`, instantiate the induction theorem explicitly. In leanprover/lean4#3505 I am fixing a big where `induction` will assume the wrong number of parameters for a case when there are let-bindings in the type involved. As part of this I am no longer reducing definitions when looking for `forall`s; this is arguably more predictable and more likely what the user wants. There are two breakages in mathlib due to this, and the fix can already be applied now.
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…1023) and in `setToL1_mono_left`, instantiate the induction theorem explicitly. In leanprover/lean4#3505 I am fixing a big where `induction` will assume the wrong number of parameters for a case when there are let-bindings in the type involved. As part of this I am no longer reducing definitions when looking for `forall`s; this is arguably more predictable and more likely what the user wants. There are two breakages in mathlib due to this, and the fix can already be applied now.
Louddy
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…1023) and in `setToL1_mono_left`, instantiate the induction theorem explicitly. In leanprover/lean4#3505 I am fixing a big where `induction` will assume the wrong number of parameters for a case when there are let-bindings in the type involved. As part of this I am no longer reducing definitions when looking for `forall`s; this is arguably more predictable and more likely what the user wants. There are two breakages in mathlib due to this, and the fix can already be applied now.
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and in
setToL1_mono_left, instantiate the induction theoremexplicitly.
In leanprover/lean4#3505 I am fixing a big where
inductionwill assume the wrong number of parameters for a case whenthere are let-bindings in the type involved. As part of this I am no
longer reducing definitions when looking for
foralls; this is arguablymore predictable and more likely what the user wants.
There are two breakages in mathlib due to this, and the fix can already
be applied now.