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chore(Algebra/Group/Units/Hom): Remove FunLike from IsLocalHom #39688

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chore(Algebra/Group/Units/Hom): Remove FunLike from IsLocalHom #39688

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4 changes: 2 additions & 2 deletions Mathlib/Algebra/Group/Units/Hom.lean
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Expand Up @@ -267,11 +267,11 @@ variable [Monoid R] [Monoid S] [Monoid T] [FunLike F R S]
whenever `f a` is a unit. See `IsLocalRing.local_hom_TFAE` for other equivalent
definitions in the local ring case - from where this concept originates, but it is useful in
other contexts, so we allow this generalisation in mathlib. -/
class IsLocalHom (f : F) : Prop where
class IsLocalHom (f : R → S) : Prop where
/-- A local homomorphism `f : R ⟶ S` will send nonunits of `R` to nonunits of `S`. -/
map_nonunit : ∀ a, IsUnit (f a) → IsUnit a

theorem IsUnit.of_map (f : F) [IsLocalHom f] (a : R) (h : IsUnit (f a)) : IsUnit a :=
theorem IsUnit.of_map (f : R → S) [IsLocalHom f] (a : R) (h : IsUnit (f a)) : IsUnit a :=
IsLocalHom.map_nonunit a h

-- TODO : remove alias, change the parenthesis of `f` and `a`
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