category_theory.limits.shapes.reflexive

Changes since the initial port

The following section lists changes to this file in mathlib3 and mathlib4 that occured after the initial port. Most recent changes are shown first. Hovering over a commit will show all commits associated with the same mathlib3 commit.

Changes in mathlib3

d6814c58

(last sync)

Changes in mathlib3port

mathlib3

mathlib3port

97eab485

bump to nightly-2024-02-05-08

mathlib commit https://github.com/leanprover-community/mathlib/commit/65a1391a0106c9204fe45bc73a039f056558cb83

516c6ec2

Diff

@@ -43,7 +43,7 @@ variable {D : Type u₂} [Category.{v₂} D]
 variable {A B : C} {f g : A ⟶ B}
 
 #print CategoryTheory.IsReflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:404:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:400:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
 /-- The pair `f g : A ⟶ B` is reflexive if there is a morphism `B ⟶ A` which is a section for both.
 -/
 class IsReflexivePair (f g : A ⟶ B) : Prop where
@@ -52,7 +52,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
 -/
 
 #print CategoryTheory.IsCoreflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:404:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:400:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
 /--
 The pair `f g : A ⟶ B` is coreflexive if there is a morphism `B ⟶ A` which is a retraction for both.
 -/

97eab485

bump to nightly-2023-12-23-06

mathlib commit https://github.com/leanprover-community/mathlib/commit/65a1391a0106c9204fe45bc73a039f056558cb83

b8c74971

Diff

@@ -43,7 +43,7 @@ variable {D : Type u₂} [Category.{v₂} D]
 variable {A B : C} {f g : A ⟶ B}
 
 #print CategoryTheory.IsReflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:394:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:404:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
 /-- The pair `f g : A ⟶ B` is reflexive if there is a morphism `B ⟶ A` which is a section for both.
 -/
 class IsReflexivePair (f g : A ⟶ B) : Prop where
@@ -52,7 +52,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
 -/
 
 #print CategoryTheory.IsCoreflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:394:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:404:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
 /--
 The pair `f g : A ⟶ B` is coreflexive if there is a morphism `B ⟶ A` which is a retraction for both.
 -/

97eab485

bump to nightly-2023-09-24-06

mathlib commit https://github.com/leanprover-community/mathlib/commit/ce64cd319bb6b3e82f31c2d38e79080d377be451

5655435f

Diff

@@ -3,8 +3,8 @@ Copyright (c) 2020 Bhavik Mehta. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Bhavik Mehta
 -/
-import Mathbin.CategoryTheory.Limits.Shapes.Equalizers
-import Mathbin.CategoryTheory.Limits.Shapes.KernelPair
+import CategoryTheory.Limits.Shapes.Equalizers
+import CategoryTheory.Limits.Shapes.KernelPair
 
 #align_import category_theory.limits.shapes.reflexive from "leanprover-community/mathlib"@"97eab48559068f3d6313da387714ef25768fb730"
 
@@ -43,7 +43,7 @@ variable {D : Type u₂} [Category.{v₂} D]
 variable {A B : C} {f g : A ⟶ B}
 
 #print CategoryTheory.IsReflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:393:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:394:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
 /-- The pair `f g : A ⟶ B` is reflexive if there is a morphism `B ⟶ A` which is a section for both.
 -/
 class IsReflexivePair (f g : A ⟶ B) : Prop where
@@ -52,7 +52,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
 -/
 
 #print CategoryTheory.IsCoreflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:393:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:394:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
 /--
 The pair `f g : A ⟶ B` is coreflexive if there is a morphism `B ⟶ A` which is a retraction for both.
 -/

97eab485

bump to nightly-2023-07-20-09

mathlib commit https://github.com/leanprover-community/mathlib/commit/8ea5598db6caeddde6cb734aa179cc2408dbd345

9c56d0dd

Diff

@@ -2,15 +2,12 @@
 Copyright (c) 2020 Bhavik Mehta. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Bhavik Mehta
-
-! This file was ported from Lean 3 source module category_theory.limits.shapes.reflexive
-! leanprover-community/mathlib commit 97eab48559068f3d6313da387714ef25768fb730
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathbin.CategoryTheory.Limits.Shapes.Equalizers
 import Mathbin.CategoryTheory.Limits.Shapes.KernelPair
 
+#align_import category_theory.limits.shapes.reflexive from "leanprover-community/mathlib"@"97eab48559068f3d6313da387714ef25768fb730"
+
 /-!
 # Reflexive coequalizers

97eab485

bump to nightly-2023-06-13-21

mathlib commit https://github.com/leanprover-community/mathlib/commit/9fb8964792b4237dac6200193a0d533f1b3f7423

829520ac

Diff

@@ -46,7 +46,7 @@ variable {D : Type u₂} [Category.{v₂} D]
 variable {A B : C} {f g : A ⟶ B}
 
 #print CategoryTheory.IsReflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:394:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:393:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
 /-- The pair `f g : A ⟶ B` is reflexive if there is a morphism `B ⟶ A` which is a section for both.
 -/
 class IsReflexivePair (f g : A ⟶ B) : Prop where
@@ -55,7 +55,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
 -/
 
 #print CategoryTheory.IsCoreflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:394:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:393:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
 /--
 The pair `f g : A ⟶ B` is coreflexive if there is a morphism `B ⟶ A` which is a retraction for both.
 -/

97eab485

bump to nightly-2023-06-04-18

mathlib commit https://github.com/leanprover-community/mathlib/commit/5f25c089cb34db4db112556f23c50d12da81b297

3fb4268b

Diff

@@ -46,7 +46,7 @@ variable {D : Type u₂} [Category.{v₂} D]
 variable {A B : C} {f g : A ⟶ B}
 
 #print CategoryTheory.IsReflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:393:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:394:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
 /-- The pair `f g : A ⟶ B` is reflexive if there is a morphism `B ⟶ A` which is a section for both.
 -/
 class IsReflexivePair (f g : A ⟶ B) : Prop where
@@ -55,7 +55,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
 -/
 
 #print CategoryTheory.IsCoreflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:393:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:394:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
 /--
 The pair `f g : A ⟶ B` is coreflexive if there is a morphism `B ⟶ A` which is a retraction for both.
 -/

97eab485

bump to nightly-2023-05-28-04

mathlib commit https://github.com/leanprover-community/mathlib/commit/917c3c072e487b3cccdbfeff17e75b40e45f66cb

6797a637

Diff

@@ -152,9 +152,7 @@ variable {F : C ⥤ D} {G : D ⥤ C} (adj : F ⊣ G)
 instance (B : D) :
     IsReflexivePair (F.map (G.map (adj.counit.app B))) (adj.counit.app (F.obj (G.obj B))) :=
   IsReflexivePair.mk' (F.map (adj.Unit.app (G.obj B)))
-    (by
-      rw [← F.map_comp, adj.right_triangle_components]
-      apply F.map_id)
+    (by rw [← F.map_comp, adj.right_triangle_components]; apply F.map_id)
     adj.left_triangle_components
 
 namespace Limits

97eab485

bump to nightly-2023-05-23-03

mathlib commit https://github.com/leanprover-community/mathlib/commit/75e7fca56381d056096ce5d05e938f63a6567828

ed98987c

Diff

@@ -86,14 +86,14 @@ noncomputable def commonSection (f g : A ⟶ B) [IsReflexivePair f g] : B ⟶ A
 -/
 
 #print CategoryTheory.section_comp_left /-
-@[simp, reassoc.1]
+@[simp, reassoc]
 theorem section_comp_left (f g : A ⟶ B) [IsReflexivePair f g] : commonSection f g ≫ f = 𝟙 B :=
   (IsReflexivePair.common_section f g).choose_spec.1
 #align category_theory.section_comp_left CategoryTheory.section_comp_left
 -/
 
 #print CategoryTheory.section_comp_right /-
-@[simp, reassoc.1]
+@[simp, reassoc]
 theorem section_comp_right (f g : A ⟶ B) [IsReflexivePair f g] : commonSection f g ≫ g = 𝟙 B :=
   (IsReflexivePair.common_section f g).choose_spec.2
 #align category_theory.section_comp_right CategoryTheory.section_comp_right
@@ -107,7 +107,7 @@ noncomputable def commonRetraction (f g : A ⟶ B) [IsCoreflexivePair f g] : B 
 -/
 
 #print CategoryTheory.left_comp_retraction /-
-@[simp, reassoc.1]
+@[simp, reassoc]
 theorem left_comp_retraction (f g : A ⟶ B) [IsCoreflexivePair f g] :
     f ≫ commonRetraction f g = 𝟙 A :=
   (IsCoreflexivePair.common_retraction f g).choose_spec.1
@@ -115,7 +115,7 @@ theorem left_comp_retraction (f g : A ⟶ B) [IsCoreflexivePair f g] :
 -/
 
 #print CategoryTheory.right_comp_retraction /-
-@[simp, reassoc.1]
+@[simp, reassoc]
 theorem right_comp_retraction (f g : A ⟶ B) [IsCoreflexivePair f g] :
     g ≫ commonRetraction f g = 𝟙 A :=
   (IsCoreflexivePair.common_retraction f g).choose_spec.2

97eab485

bump to nightly-2023-04-24-06

mathlib commit https://github.com/leanprover-community/mathlib/commit/09079525fd01b3dda35e96adaa08d2f943e1648c

ff662d55

Diff

@@ -46,7 +46,7 @@ variable {D : Type u₂} [Category.{v₂} D]
 variable {A B : C} {f g : A ⟶ B}
 
 #print CategoryTheory.IsReflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:388:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:393:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
 /-- The pair `f g : A ⟶ B` is reflexive if there is a morphism `B ⟶ A` which is a section for both.
 -/
 class IsReflexivePair (f g : A ⟶ B) : Prop where
@@ -55,7 +55,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
 -/
 
 #print CategoryTheory.IsCoreflexivePair /-
-/- ./././Mathport/Syntax/Translate/Command.lean:388:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
+/- ./././Mathport/Syntax/Translate/Command.lean:393:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
 /--
 The pair `f g : A ⟶ B` is coreflexive if there is a morphism `B ⟶ A` which is a retraction for both.
 -/
@@ -175,9 +175,9 @@ class HasCoreflexiveEqualizers : Prop where
 #align category_theory.limits.has_coreflexive_equalizers CategoryTheory.Limits.HasCoreflexiveEqualizers
 -/
 
-attribute [instance] has_reflexive_coequalizers.has_coeq
+attribute [instance 1] has_reflexive_coequalizers.has_coeq
 
-attribute [instance] has_coreflexive_equalizers.has_eq
+attribute [instance 1] has_coreflexive_equalizers.has_eq
 
 #print CategoryTheory.Limits.hasCoequalizer_of_common_section /-
 theorem hasCoequalizer_of_common_section [HasReflexiveCoequalizers C] {A B : C} {f g : A ⟶ B}

97eab485

bump to nightly-2023-03-25-02

mathlib commit https://github.com/leanprover-community/mathlib/commit/d11893b411025250c8e61ff2f12ccbd7ee35ab15

9ce440f0

Diff

@@ -4,7 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Bhavik Mehta
 
 ! This file was ported from Lean 3 source module category_theory.limits.shapes.reflexive
-! leanprover-community/mathlib commit d6814c584384ddf2825ff038e868451a7c956f31
+! leanprover-community/mathlib commit 97eab48559068f3d6313da387714ef25768fb730
 ! Please do not edit these lines, except to modify the commit id
 ! if you have ported upstream changes.
 -/
@@ -14,6 +14,9 @@ import Mathbin.CategoryTheory.Limits.Shapes.KernelPair
 /-!
 # Reflexive coequalizers
 
+> THIS FILE IS SYNCHRONIZED WITH MATHLIB4.
+> Any changes to this file require a corresponding PR to mathlib4.
+
 We define reflexive pairs as a pair of morphisms which have a common section. We say a category has
 reflexive coequalizers if it has coequalizers of all reflexive pairs.
 Reflexive coequalizers often enjoy nicer properties than general coequalizers, and feature heavily

d6814c58

bump to nightly-2023-03-23-14

mathlib commit https://github.com/leanprover-community/mathlib/commit/57e09a1296bfb4330ddf6624f1028ba186117d82

15f1b32d

Diff

@@ -42,13 +42,16 @@ variable {D : Type u₂} [Category.{v₂} D]
 
 variable {A B : C} {f g : A ⟶ B}
 
+#print CategoryTheory.IsReflexivePair /-
 /- ./././Mathport/Syntax/Translate/Command.lean:388:30: infer kinds are unsupported in Lean 4: #[`common_section] [] -/
 /-- The pair `f g : A ⟶ B` is reflexive if there is a morphism `B ⟶ A` which is a section for both.
 -/
 class IsReflexivePair (f g : A ⟶ B) : Prop where
   common_section : ∃ s : B ⟶ A, s ≫ f = 𝟙 B ∧ s ≫ g = 𝟙 B
 #align category_theory.is_reflexive_pair CategoryTheory.IsReflexivePair
+-/
 
+#print CategoryTheory.IsCoreflexivePair /-
 /- ./././Mathport/Syntax/Translate/Command.lean:388:30: infer kinds are unsupported in Lean 4: #[`common_retraction] [] -/
 /--
 The pair `f g : A ⟶ B` is coreflexive if there is a morphism `B ⟶ A` which is a retraction for both.
@@ -56,66 +59,89 @@ The pair `f g : A ⟶ B` is coreflexive if there is a morphism `B ⟶ A` which i
 class IsCoreflexivePair (f g : A ⟶ B) : Prop where
   common_retraction : ∃ s : B ⟶ A, f ≫ s = 𝟙 A ∧ g ≫ s = 𝟙 A
 #align category_theory.is_coreflexive_pair CategoryTheory.IsCoreflexivePair
+-/
 
+#print CategoryTheory.IsReflexivePair.mk' /-
 theorem IsReflexivePair.mk' (s : B ⟶ A) (sf : s ≫ f = 𝟙 B) (sg : s ≫ g = 𝟙 B) :
     IsReflexivePair f g :=
   ⟨⟨s, sf, sg⟩⟩
 #align category_theory.is_reflexive_pair.mk' CategoryTheory.IsReflexivePair.mk'
+-/
 
+#print CategoryTheory.IsCoreflexivePair.mk' /-
 theorem IsCoreflexivePair.mk' (s : B ⟶ A) (fs : f ≫ s = 𝟙 A) (gs : g ≫ s = 𝟙 A) :
     IsCoreflexivePair f g :=
   ⟨⟨s, fs, gs⟩⟩
 #align category_theory.is_coreflexive_pair.mk' CategoryTheory.IsCoreflexivePair.mk'
+-/
 
+#print CategoryTheory.commonSection /-
 /-- Get the common section for a reflexive pair. -/
 noncomputable def commonSection (f g : A ⟶ B) [IsReflexivePair f g] : B ⟶ A :=
   (IsReflexivePair.common_section f g).some
 #align category_theory.common_section CategoryTheory.commonSection
+-/
 
+#print CategoryTheory.section_comp_left /-
 @[simp, reassoc.1]
 theorem section_comp_left (f g : A ⟶ B) [IsReflexivePair f g] : commonSection f g ≫ f = 𝟙 B :=
   (IsReflexivePair.common_section f g).choose_spec.1
 #align category_theory.section_comp_left CategoryTheory.section_comp_left
+-/
 
+#print CategoryTheory.section_comp_right /-
 @[simp, reassoc.1]
 theorem section_comp_right (f g : A ⟶ B) [IsReflexivePair f g] : commonSection f g ≫ g = 𝟙 B :=
   (IsReflexivePair.common_section f g).choose_spec.2
 #align category_theory.section_comp_right CategoryTheory.section_comp_right
+-/
 
+#print CategoryTheory.commonRetraction /-
 /-- Get the common retraction for a coreflexive pair. -/
 noncomputable def commonRetraction (f g : A ⟶ B) [IsCoreflexivePair f g] : B ⟶ A :=
   (IsCoreflexivePair.common_retraction f g).some
 #align category_theory.common_retraction CategoryTheory.commonRetraction
+-/
 
+#print CategoryTheory.left_comp_retraction /-
 @[simp, reassoc.1]
 theorem left_comp_retraction (f g : A ⟶ B) [IsCoreflexivePair f g] :
     f ≫ commonRetraction f g = 𝟙 A :=
   (IsCoreflexivePair.common_retraction f g).choose_spec.1
 #align category_theory.left_comp_retraction CategoryTheory.left_comp_retraction
+-/
 
+#print CategoryTheory.right_comp_retraction /-
 @[simp, reassoc.1]
 theorem right_comp_retraction (f g : A ⟶ B) [IsCoreflexivePair f g] :
     g ≫ commonRetraction f g = 𝟙 A :=
   (IsCoreflexivePair.common_retraction f g).choose_spec.2
 #align category_theory.right_comp_retraction CategoryTheory.right_comp_retraction
+-/
 
+#print CategoryTheory.IsKernelPair.isReflexivePair /-
 /-- If `f,g` is a kernel pair for some morphism `q`, then it is reflexive. -/
 theorem IsKernelPair.isReflexivePair {R : C} {f g : R ⟶ A} {q : A ⟶ B} (h : IsKernelPair q f g) :
     IsReflexivePair f g :=
   IsReflexivePair.mk' _ (h.lift' _ _ rfl).2.1 (h.lift' _ _ _).2.2
 #align category_theory.is_kernel_pair.is_reflexive_pair CategoryTheory.IsKernelPair.isReflexivePair
+-/
 
+#print CategoryTheory.IsReflexivePair.swap /-
 -- This shouldn't be an instance as it would instantly loop.
 /-- If `f,g` is reflexive, then `g,f` is reflexive. -/
 theorem IsReflexivePair.swap [IsReflexivePair f g] : IsReflexivePair g f :=
   IsReflexivePair.mk' _ (section_comp_right f g) (section_comp_left f g)
 #align category_theory.is_reflexive_pair.swap CategoryTheory.IsReflexivePair.swap
+-/
 
+#print CategoryTheory.IsCoreflexivePair.swap /-
 -- This shouldn't be an instance as it would instantly loop.
 /-- If `f,g` is coreflexive, then `g,f` is coreflexive. -/
 theorem IsCoreflexivePair.swap [IsCoreflexivePair f g] : IsCoreflexivePair g f :=
   IsCoreflexivePair.mk' _ (right_comp_retraction f g) (left_comp_retraction f g)
 #align category_theory.is_coreflexive_pair.swap CategoryTheory.IsCoreflexivePair.swap
+-/
 
 variable {F : C ⥤ D} {G : D ⥤ C} (adj : F ⊣ G)
 
@@ -132,43 +158,55 @@ namespace Limits
 
 variable (C)
 
+#print CategoryTheory.Limits.HasReflexiveCoequalizers /-
 /-- `C` has reflexive coequalizers if it has coequalizers for every reflexive pair. -/
 class HasReflexiveCoequalizers : Prop where
   has_coeq : ∀ ⦃A B : C⦄ (f g : A ⟶ B) [IsReflexivePair f g], HasCoequalizer f g
 #align category_theory.limits.has_reflexive_coequalizers CategoryTheory.Limits.HasReflexiveCoequalizers
+-/
 
+#print CategoryTheory.Limits.HasCoreflexiveEqualizers /-
 /-- `C` has coreflexive equalizers if it has equalizers for every coreflexive pair. -/
 class HasCoreflexiveEqualizers : Prop where
   has_eq : ∀ ⦃A B : C⦄ (f g : A ⟶ B) [IsCoreflexivePair f g], HasEqualizer f g
 #align category_theory.limits.has_coreflexive_equalizers CategoryTheory.Limits.HasCoreflexiveEqualizers
+-/
 
 attribute [instance] has_reflexive_coequalizers.has_coeq
 
 attribute [instance] has_coreflexive_equalizers.has_eq
 
+#print CategoryTheory.Limits.hasCoequalizer_of_common_section /-
 theorem hasCoequalizer_of_common_section [HasReflexiveCoequalizers C] {A B : C} {f g : A ⟶ B}
     (r : B ⟶ A) (rf : r ≫ f = 𝟙 _) (rg : r ≫ g = 𝟙 _) : HasCoequalizer f g :=
   by
   letI := is_reflexive_pair.mk' r rf rg
   infer_instance
 #align category_theory.limits.has_coequalizer_of_common_section CategoryTheory.Limits.hasCoequalizer_of_common_section
+-/
 
+#print CategoryTheory.Limits.hasEqualizer_of_common_retraction /-
 theorem hasEqualizer_of_common_retraction [HasCoreflexiveEqualizers C] {A B : C} {f g : A ⟶ B}
     (r : B ⟶ A) (fr : f ≫ r = 𝟙 _) (gr : g ≫ r = 𝟙 _) : HasEqualizer f g :=
   by
   letI := is_coreflexive_pair.mk' r fr gr
   infer_instance
 #align category_theory.limits.has_equalizer_of_common_retraction CategoryTheory.Limits.hasEqualizer_of_common_retraction
+-/
 
+#print CategoryTheory.Limits.hasReflexiveCoequalizers_of_hasCoequalizers /-
 /-- If `C` has coequalizers, then it has reflexive coequalizers. -/
 instance (priority := 100) hasReflexiveCoequalizers_of_hasCoequalizers [HasCoequalizers C] :
     HasReflexiveCoequalizers C where has_coeq A B f g i := by infer_instance
 #align category_theory.limits.has_reflexive_coequalizers_of_has_coequalizers CategoryTheory.Limits.hasReflexiveCoequalizers_of_hasCoequalizers
+-/
 
+#print CategoryTheory.Limits.hasCoreflexiveEqualizers_of_hasEqualizers /-
 /-- If `C` has equalizers, then it has coreflexive equalizers. -/
 instance (priority := 100) hasCoreflexiveEqualizers_of_hasEqualizers [HasEqualizers C] :
     HasCoreflexiveEqualizers C where has_eq A B f g i := by infer_instance
 #align category_theory.limits.has_coreflexive_equalizers_of_has_equalizers CategoryTheory.Limits.hasCoreflexiveEqualizers_of_hasEqualizers
+-/
 
 end Limits

d6814c58

bump to nightly-2023-02-21-16

mathlib commit https://github.com/leanprover-community/mathlib/commit/bd9851ca476957ea4549eb19b40e7b5ade9428cc

1107b979

Changes in mathlib4

mathlib3

mathlib4

d6814c58

chore(*): remove empty lines between variable statements (#11418)

Empty lines were removed by executing the following Python script twice

import os
import re


# Loop through each file in the repository
for dir_path, dirs, files in os.walk('.'):
  for filename in files:
    if filename.endswith('.lean'):
      file_path = os.path.join(dir_path, filename)

      # Open the file and read its contents
      with open(file_path, 'r') as file:
        content = file.read()

      # Use a regular expression to replace sequences of "variable" lines separated by empty lines
      # with sequences without empty lines
      modified_content = re.sub(r'(variable.*\n)\n(variable(?! .* in))', r'\1\2', content)

      # Write the modified content back to the file
      with open(file_path, 'w') as file:
        file.write(modified_content)

75c86f04

Diff

@@ -34,9 +34,7 @@ namespace CategoryTheory
 universe v v₂ u u₂
 
 variable {C : Type u} [Category.{v} C]
-
 variable {D : Type u₂} [Category.{v₂} D]
-
 variable {A B : C} {f g : A ⟶ B}
 
 /-- The pair `f g : A ⟶ B` is reflexive if there is a morphism `B ⟶ A` which is a section for both.

d6814c58

chore: classify new theorem / theorem porting notes (#11432)

Classifies by adding issue number #10756 to porting notes claiming anything equivalent to:

"added theorem"
"added theorems"
"new theorem"
"new theorems"
"added lemma"
"new lemma"
"new lemmas"

55fe4027

Diff

@@ -45,7 +45,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
   common_section' : ∃ s : B ⟶ A, s ≫ f = 𝟙 B ∧ s ≫ g = 𝟙 B
 #align category_theory.is_reflexive_pair CategoryTheory.IsReflexivePair
 
--- Porting note: added theorem, because of unsupported infer kinds
+-- Porting note (#10756): added theorem, because of unsupported infer kinds
 theorem IsReflexivePair.common_section (f g : A ⟶ B) [IsReflexivePair f g] :
     ∃ s : B ⟶ A, s ≫ f = 𝟙 B ∧ s ≫ g = 𝟙 B := IsReflexivePair.common_section'
 
@@ -56,7 +56,7 @@ class IsCoreflexivePair (f g : A ⟶ B) : Prop where
   common_retraction' : ∃ s : B ⟶ A, f ≫ s = 𝟙 A ∧ g ≫ s = 𝟙 A
 #align category_theory.is_coreflexive_pair CategoryTheory.IsCoreflexivePair
 
--- Porting note: added theorem, because of unsupported infer kinds
+-- Porting note (#10756): added theorem, because of unsupported infer kinds
 theorem IsCoreflexivePair.common_retraction (f g : A ⟶ B) [IsCoreflexivePair f g] :
     ∃ s : B ⟶ A, f ≫ s = 𝟙 A ∧ g ≫ s = 𝟙 A := IsCoreflexivePair.common_retraction'

d6814c58

style: homogenise porting notes (#11145)

Homogenises porting notes via capitalisation and addition of whitespace.

It makes the following changes:

converts "--porting note" into "-- Porting note";
converts "porting note" into "Porting note".

8be0b69c

Diff

@@ -45,7 +45,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
   common_section' : ∃ s : B ⟶ A, s ≫ f = 𝟙 B ∧ s ≫ g = 𝟙 B
 #align category_theory.is_reflexive_pair CategoryTheory.IsReflexivePair
 
--- porting note: added theorem, because of unsupported infer kinds
+-- Porting note: added theorem, because of unsupported infer kinds
 theorem IsReflexivePair.common_section (f g : A ⟶ B) [IsReflexivePair f g] :
     ∃ s : B ⟶ A, s ≫ f = 𝟙 B ∧ s ≫ g = 𝟙 B := IsReflexivePair.common_section'
 
@@ -56,7 +56,7 @@ class IsCoreflexivePair (f g : A ⟶ B) : Prop where
   common_retraction' : ∃ s : B ⟶ A, f ≫ s = 𝟙 A ∧ g ≫ s = 𝟙 A
 #align category_theory.is_coreflexive_pair CategoryTheory.IsCoreflexivePair
 
--- porting note: added theorem, because of unsupported infer kinds
+-- Porting note: added theorem, because of unsupported infer kinds
 theorem IsCoreflexivePair.common_retraction (f g : A ⟶ B) [IsCoreflexivePair f g] :
     ∃ s : B ⟶ A, f ≫ s = 𝟙 A ∧ g ≫ s = 𝟙 A := IsCoreflexivePair.common_retraction'

d6814c58

feat(CategoryTheory): prerequisites for the existence of finite products in localized categories (#9702)

This PR contains various prerequisites in order to show that under suitable assumptions, a localized category of a category that has finite products also has finite products:

the equivalence of categories (J → C) ≌ (Discrete J ⥤ C)
more API for the existence of limits as a consequence of a right adjoint to the constant functor C ⥤ (J ⥤ C).
the typeclass MorphismProperty.IsStableUnderFiniteProducts

00c3cd40

Diff

@@ -129,7 +129,7 @@ instance (B : D) :
     (by
       rw [← F.map_comp, adj.right_triangle_components]
       apply F.map_id)
-    adj.left_triangle_components
+    (adj.left_triangle_components _)
 
 namespace Limits

d6814c58

chore: only four spaces for subsequent lines (#7286)

Co-authored-by: Moritz Firsching <firsching@google.com>

0c7d6fa5

Diff

@@ -47,7 +47,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
 
 -- porting note: added theorem, because of unsupported infer kinds
 theorem IsReflexivePair.common_section (f g : A ⟶ B) [IsReflexivePair f g] :
-  ∃ s : B ⟶ A, s ≫ f = 𝟙 B ∧ s ≫ g = 𝟙 B := IsReflexivePair.common_section'
+    ∃ s : B ⟶ A, s ≫ f = 𝟙 B ∧ s ≫ g = 𝟙 B := IsReflexivePair.common_section'
 
 /--
 The pair `f g : A ⟶ B` is coreflexive if there is a morphism `B ⟶ A` which is a retraction for both.
@@ -58,7 +58,7 @@ class IsCoreflexivePair (f g : A ⟶ B) : Prop where
 
 -- porting note: added theorem, because of unsupported infer kinds
 theorem IsCoreflexivePair.common_retraction (f g : A ⟶ B) [IsCoreflexivePair f g] :
-  ∃ s : B ⟶ A, f ≫ s = 𝟙 A ∧ g ≫ s = 𝟙 A := IsCoreflexivePair.common_retraction'
+    ∃ s : B ⟶ A, f ≫ s = 𝟙 A ∧ g ≫ s = 𝟙 A := IsCoreflexivePair.common_retraction'
 
 theorem IsReflexivePair.mk' (s : B ⟶ A) (sf : s ≫ f = 𝟙 B) (sg : s ≫ g = 𝟙 B) :
     IsReflexivePair f g :=

d6814c58

chore: script to replace headers with #align_import statements (#5979)

depends on: #5966

Co-authored-by: Eric Wieser <wieser.eric@gmail.com> Co-authored-by: Scott Morrison <scott.morrison@gmail.com>

89aa3a3b

Diff

@@ -2,15 +2,12 @@
 Copyright (c) 2020 Bhavik Mehta. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Bhavik Mehta
-
-! This file was ported from Lean 3 source module category_theory.limits.shapes.reflexive
-! leanprover-community/mathlib commit d6814c584384ddf2825ff038e868451a7c956f31
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathlib.CategoryTheory.Limits.Shapes.Equalizers
 import Mathlib.CategoryTheory.Limits.Shapes.KernelPair
 
+#align_import category_theory.limits.shapes.reflexive from "leanprover-community/mathlib"@"d6814c584384ddf2825ff038e868451a7c956f31"
+
 /-!
 # Reflexive coequalizers

d6814c58

chore: formatting issues (#4947)

Co-authored-by: Scott Morrison <scott.morrison@anu.edu.au> Co-authored-by: Parcly Taxel <reddeloostw@gmail.com>

5068808d

Diff

@@ -49,7 +49,7 @@ class IsReflexivePair (f g : A ⟶ B) : Prop where
 #align category_theory.is_reflexive_pair CategoryTheory.IsReflexivePair
 
 -- porting note: added theorem, because of unsupported infer kinds
-theorem IsReflexivePair.common_section (f g : A ⟶ B) [IsReflexivePair f g]:
+theorem IsReflexivePair.common_section (f g : A ⟶ B) [IsReflexivePair f g] :
   ∃ s : B ⟶ A, s ≫ f = 𝟙 B ∧ s ≫ g = 𝟙 B := IsReflexivePair.common_section'
 
 /--
@@ -60,7 +60,7 @@ class IsCoreflexivePair (f g : A ⟶ B) : Prop where
 #align category_theory.is_coreflexive_pair CategoryTheory.IsCoreflexivePair
 
 -- porting note: added theorem, because of unsupported infer kinds
-theorem IsCoreflexivePair.common_retraction (f g : A ⟶ B) [IsCoreflexivePair f g]:
+theorem IsCoreflexivePair.common_retraction (f g : A ⟶ B) [IsCoreflexivePair f g] :
   ∃ s : B ⟶ A, f ≫ s = 𝟙 A ∧ g ≫ s = 𝟙 A := IsCoreflexivePair.common_retraction'
 
 theorem IsReflexivePair.mk' (s : B ⟶ A) (sf : s ≫ f = 𝟙 B) (sg : s ≫ g = 𝟙 B) :

d6814c58

chore: port missing instance priorities (#3613)

See discussion at https://leanprover.zulipchat.com/#narrow/stream/287929-mathlib4/topic/mathport.20drops.20priorities.20in.20.60attribute.20.5Binstance.5D.60. mathport has been dropping the priorities on instances when using the attribute command.

This PR adds back all the priorities, except for local attribute, and instances involving coercions, which I didn't want to mess with.

Co-authored-by: Scott Morrison <scott.morrison@gmail.com>

b0c1460c

Diff

@@ -148,9 +148,9 @@ class HasCoreflexiveEqualizers : Prop where
   has_eq : ∀ ⦃A B : C⦄ (f g : A ⟶ B) [IsCoreflexivePair f g], HasEqualizer f g
 #align category_theory.limits.has_coreflexive_equalizers CategoryTheory.Limits.HasCoreflexiveEqualizers
 
-attribute [instance] HasReflexiveCoequalizers.has_coeq
+attribute [instance 1] HasReflexiveCoequalizers.has_coeq
 
-attribute [instance] HasCoreflexiveEqualizers.has_eq
+attribute [instance 1] HasCoreflexiveEqualizers.has_eq
 
 theorem hasCoequalizer_of_common_section [HasReflexiveCoequalizers C] {A B : C} {f g : A ⟶ B}
     (r : B ⟶ A) (rf : r ≫ f = 𝟙 _) (rg : r ≫ g = 𝟙 _) : HasCoequalizer f g := by

d6814c58

feat: port CategoryTheory.Limits.Shapes.Reflexive (#3041)

Co-authored-by: Moritz Firsching <firsching@google.com>

ddbb81cc

`category_theory.limits.shapes.reflexive` ⟷ `Mathlib.CategoryTheory.Limits.Shapes.Reflexive`

Changes since the initial port

Changes in mathlib3

Changes in mathlib3port

Changes in mathlib4

Dependencies 2 + 253

category_theory.limits.shapes.reflexive ⟷ Mathlib.CategoryTheory.Limits.Shapes.Reflexive

Changes since the initial port

Changes in mathlib3

Changes in mathlib3port

Changes in mathlib4

Dependencies 2 + 253

`category_theory.limits.shapes.reflexive` ⟷ `Mathlib.CategoryTheory.Limits.Shapes.Reflexive`