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[Merged by Bors] - fix(category_theory/adjunction/limits): remove bad instance #9157

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[Merged by Bors] - fix(category_theory/adjunction/limits): remove bad instance #9157

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8 changes: 4 additions & 4 deletions src/category_theory/adjunction/limits.lean
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Original file line number Diff line number Diff line change
Expand Up @@ -103,7 +103,7 @@ example (E : C ⥤ D) [is_equivalence E]
(c : cocone K) (h : is_colimit c) : is_colimit (E.map_cocone c) :=
preserves_colimit.preserves h

instance has_colimit_comp_equivalence (E : C ⥤ D) [is_equivalence E] [has_colimit K] :
lemma has_colimit_comp_equivalence (E : C ⥤ D) [is_equivalence E] [has_colimit K] :
has_colimit (K ⋙ E) :=
has_colimit.mk
{ cocone := E.map_cocone (colimit.cocone K),
Expand All @@ -112,7 +112,7 @@ has_colimit.mk
lemma has_colimit_of_comp_equivalence (E : C ⥤ D) [is_equivalence E] [has_colimit (K ⋙ E)] :
has_colimit K :=
@has_colimit_of_iso _ _ _ _ (K ⋙ E ⋙ inv E) K
(@adjunction.has_colimit_comp_equivalence _ _ _ _ _ _ (K ⋙ E) (inv E) _ _)
(@has_colimit_comp_equivalence _ _ _ _ _ _ (K ⋙ E) (inv E) _ _)
((functor.right_unitor _).symm ≪≫ iso_whisker_left K (E.as_equivalence.unit_iso))

/-- Transport a `has_colimits_of_shape` instance across an equivalence. -/
Expand Down Expand Up @@ -210,7 +210,7 @@ example (E : D ⥤ C) [is_equivalence E]
(c : cone K) [h : is_limit c] : is_limit (E.map_cone c) :=
preserves_limit.preserves h

instance has_limit_comp_equivalence (E : D ⥤ C) [is_equivalence E] [has_limit K] :
lemma has_limit_comp_equivalence (E : D ⥤ C) [is_equivalence E] [has_limit K] :
has_limit (K ⋙ E) :=
has_limit.mk
{ cone := E.map_cone (limit.cone K),
Expand All @@ -219,7 +219,7 @@ has_limit.mk
lemma has_limit_of_comp_equivalence (E : D ⥤ C) [is_equivalence E] [has_limit (K ⋙ E)] :
has_limit K :=
@has_limit_of_iso _ _ _ _ (K ⋙ E ⋙ inv E) K
(@adjunction.has_limit_comp_equivalence _ _ _ _ _ _ (K ⋙ E) (inv E) _ _)
(@has_limit_comp_equivalence _ _ _ _ _ _ (K ⋙ E) (inv E) _ _)
((iso_whisker_left K E.as_equivalence.unit_iso.symm) ≪≫ (functor.right_unitor _))

/-- Transport a `has_limits_of_shape` instance across an equivalence. -/
Expand Down
6 changes: 4 additions & 2 deletions src/category_theory/limits/over.lean
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Expand Up @@ -34,7 +34,8 @@ variable {X : C}

namespace category_theory.over

instance (F : J ⥤ over X) [i : has_colimit (F ⋙ forget X)] : has_colimit F :=
instance has_colimit_of_has_colimit_comp_forget
(F : J ⥤ over X) [i : has_colimit (F ⋙ forget X)] : has_colimit F :=
@@costructured_arrow.has_colimit _ _ _ _ i _

instance [has_colimits_of_shape J C] : has_colimits_of_shape J (over X) := {}
Expand Down Expand Up @@ -107,7 +108,8 @@ end category_theory.over

namespace category_theory.under

instance (F : J ⥤ under X) [i : has_limit (F ⋙ forget X)] : has_limit F :=
instance has_limit_of_has_limit_comp_forget
(F : J ⥤ under X) [i : has_limit (F ⋙ forget X)] : has_limit F :=
@@structured_arrow.has_limit _ _ _ _ i _

instance [has_limits_of_shape J C] : has_limits_of_shape J (under X) := {}
Expand Down