algebra.group_ring_action.basic | Mathlib porting status

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

207cfac9

(last sync)

Changes in mathlib3port

mathlib3

mathlib3port

c3291da4

bump to nightly-2023-09-24-06

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

5655435f

Diff

@@ -3,9 +3,9 @@ Copyright (c) 2020 Kenny Lau. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Kenny Lau
 -/
-import Mathbin.Algebra.Ring.Equiv
-import Mathbin.Algebra.Field.Defs
-import Mathbin.GroupTheory.GroupAction.Group
+import Algebra.Ring.Equiv
+import Algebra.Field.Defs
+import GroupTheory.GroupAction.Group
 
 #align_import algebra.group_ring_action.basic from "leanprover-community/mathlib"@"c3291da49cfa65f0d43b094750541c0731edc932"

c3291da4

bump to nightly-2023-08-17-09

mathlib commit https://github.com/leanprover-community/mathlib/commit/32a7e535287f9c73f2e4d2aef306a39190f0b504

60285dcc

Diff

@@ -41,7 +41,7 @@ This combines `distrib_mul_action` with `mul_distrib_mul_action`. -/
 class MulSemiringAction (M : Type u) (R : Type v) [Monoid M] [Semiring R] extends
     DistribMulAction M R where
   smul_one : ∀ g : M, (g • 1 : R) = 1
-  smul_mul : ∀ (g : M) (x y : R), g • (x * y) = g • x * g • y
+  smul_hMul : ∀ (g : M) (x y : R), g • (x * y) = g • x * g • y
 #align mul_semiring_action MulSemiringAction
 -/

c3291da4

bump to nightly-2023-07-20-09

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

9c56d0dd

Diff

@@ -2,16 +2,13 @@
 Copyright (c) 2020 Kenny Lau. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Kenny Lau
-
-! This file was ported from Lean 3 source module algebra.group_ring_action.basic
-! leanprover-community/mathlib commit c3291da49cfa65f0d43b094750541c0731edc932
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathbin.Algebra.Ring.Equiv
 import Mathbin.Algebra.Field.Defs
 import Mathbin.GroupTheory.GroupAction.Group
 
+#align_import algebra.group_ring_action.basic from "leanprover-community/mathlib"@"c3291da49cfa65f0d43b094750541c0731edc932"
+
 /-!
 # Group action on rings

c3291da4

bump to nightly-2023-06-13-21

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

829520ac

Diff

@@ -70,16 +70,20 @@ def MulSemiringAction.toRingHom [MulSemiringAction M R] (x : M) : R →+* R :=
 #align mul_semiring_action.to_ring_hom MulSemiringAction.toRingHom
 -/
 
+#print toRingHom_injective /-
 theorem toRingHom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
     Function.Injective (MulSemiringAction.toRingHom M R) := fun m₁ m₂ h =>
   eq_of_smul_eq_smul fun r => RingHom.ext_iff.1 h r
 #align to_ring_hom_injective toRingHom_injective
+-/
 
+#print MulSemiringAction.toRingEquiv /-
 /-- Each element of the group defines a semiring isomorphism. -/
 @[simps]
 def MulSemiringAction.toRingEquiv [MulSemiringAction G R] (x : G) : R ≃+* R :=
   { DistribMulAction.toAddEquiv R x, MulSemiringAction.toRingHom G R x with }
 #align mul_semiring_action.to_ring_equiv MulSemiringAction.toRingEquiv
+-/
 
 section
 
@@ -102,12 +106,14 @@ variable {M G A R F}
 
 attribute [simp] smul_one smul_mul' smul_zero smul_add
 
+#print smul_inv'' /-
 /-- Note that `smul_inv'` refers to the group case, and `smul_inv` has an additional inverse
 on `x`. -/
 @[simp]
 theorem smul_inv'' [MulSemiringAction M F] (x : M) (m : F) : x • m⁻¹ = (x • m)⁻¹ :=
   map_inv₀ (MulSemiringAction.toRingHom M F x) _
 #align smul_inv'' smul_inv''
+-/
 
 end SimpLemmas

c3291da4

bump to nightly-2023-06-01-16

mathlib commit https://github.com/leanprover-community/mathlib/commit/cca40788df1b8755d5baf17ab2f27dacc2e17acb

b9c87c70

Diff

@@ -42,7 +42,7 @@ universe u v
 
 This combines `distrib_mul_action` with `mul_distrib_mul_action`. -/
 class MulSemiringAction (M : Type u) (R : Type v) [Monoid M] [Semiring R] extends
-  DistribMulAction M R where
+    DistribMulAction M R where
   smul_one : ∀ g : M, (g • 1 : R) = 1
   smul_mul : ∀ (g : M) (x y : R), g • (x * y) = g • x * g • y
 #align mul_semiring_action MulSemiringAction

c3291da4

bump to nightly-2023-05-28-06

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

ba5d8b97

Diff

@@ -70,23 +70,11 @@ def MulSemiringAction.toRingHom [MulSemiringAction M R] (x : M) : R →+* R :=
 #align mul_semiring_action.to_ring_hom MulSemiringAction.toRingHom
 -/
 
-/- warning: to_ring_hom_injective -> toRingHom_injective is a dubious translation:
-lean 3 declaration is
-  forall (M : Type.{u2}) [_inst_1 : Monoid.{u2} M] (R : Type.{u1}) [_inst_5 : Semiring.{u1} R] [_inst_8 : MulSemiringAction.{u2, u1} M R _inst_1 _inst_5] [_inst_9 : FaithfulSMul.{u2, u1} M R (SMulZeroClass.toHasSmul.{u2, u1} M R (AddZeroClass.toHasZero.{u1} R (AddMonoid.toAddZeroClass.{u1} R (AddMonoidWithOne.toAddMonoid.{u1} R (AddCommMonoidWithOne.toAddMonoidWithOne.{u1} R (NonAssocSemiring.toAddCommMonoidWithOne.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5)))))) (DistribSMul.toSmulZeroClass.{u2, u1} M R (AddMonoid.toAddZeroClass.{u1} R (AddMonoidWithOne.toAddMonoid.{u1} R (AddCommMonoidWithOne.toAddMonoidWithOne.{u1} R (NonAssocSemiring.toAddCommMonoidWithOne.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5))))) (DistribMulAction.toDistribSMul.{u2, u1} M R _inst_1 (AddMonoidWithOne.toAddMonoid.{u1} R (AddCommMonoidWithOne.toAddMonoidWithOne.{u1} R (NonAssocSemiring.toAddCommMonoidWithOne.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5)))) (MulSemiringAction.toDistribMulAction.{u2, u1} M R _inst_1 _inst_5 _inst_8))))], Function.Injective.{succ u2, succ u1} M (RingHom.{u1, u1} R R (Semiring.toNonAssocSemiring.{u1} R _inst_5) (Semiring.toNonAssocSemiring.{u1} R _inst_5)) (MulSemiringAction.toRingHom.{u1, u2} M _inst_1 R _inst_5 _inst_8)
-but is expected to have type
-  forall (M : Type.{u1}) [_inst_1 : Monoid.{u1} M] (R : Type.{u2}) [_inst_5 : Semiring.{u2} R] [_inst_8 : MulSemiringAction.{u1, u2} M R _inst_1 _inst_5] [_inst_9 : FaithfulSMul.{u1, u2} M R (SMulZeroClass.toSMul.{u1, u2} M R (MonoidWithZero.toZero.{u2} R (Semiring.toMonoidWithZero.{u2} R _inst_5)) (DistribSMul.toSMulZeroClass.{u1, u2} M R (AddMonoid.toAddZeroClass.{u2} R (AddMonoidWithOne.toAddMonoid.{u2} R (AddCommMonoidWithOne.toAddMonoidWithOne.{u2} R (NonAssocSemiring.toAddCommMonoidWithOne.{u2} R (Semiring.toNonAssocSemiring.{u2} R _inst_5))))) (DistribMulAction.toDistribSMul.{u1, u2} M R _inst_1 (AddMonoidWithOne.toAddMonoid.{u2} R (AddCommMonoidWithOne.toAddMonoidWithOne.{u2} R (NonAssocSemiring.toAddCommMonoidWithOne.{u2} R (Semiring.toNonAssocSemiring.{u2} R _inst_5)))) (MulSemiringAction.toDistribMulAction.{u1, u2} M R _inst_1 _inst_5 _inst_8))))], Function.Injective.{succ u1, succ u2} M (RingHom.{u2, u2} R R (Semiring.toNonAssocSemiring.{u2} R _inst_5) (Semiring.toNonAssocSemiring.{u2} R _inst_5)) (MulSemiringAction.toRingHom.{u2, u1} M _inst_1 R _inst_5 _inst_8)
-Case conversion may be inaccurate. Consider using '#align to_ring_hom_injective toRingHom_injectiveₓ'. -/
 theorem toRingHom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
     Function.Injective (MulSemiringAction.toRingHom M R) := fun m₁ m₂ h =>
   eq_of_smul_eq_smul fun r => RingHom.ext_iff.1 h r
 #align to_ring_hom_injective toRingHom_injective
 
-/- warning: mul_semiring_action.to_ring_equiv -> MulSemiringAction.toRingEquiv is a dubious translation:
-lean 3 declaration is
-  forall (G : Type.{u2}) [_inst_3 : Group.{u2} G] (R : Type.{u1}) [_inst_5 : Semiring.{u1} R] [_inst_8 : MulSemiringAction.{u2, u1} G R (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_3)) _inst_5], G -> (RingEquiv.{u1, u1} R R (Distrib.toHasMul.{u1} R (NonUnitalNonAssocSemiring.toDistrib.{u1} R (NonAssocSemiring.toNonUnitalNonAssocSemiring.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5)))) (Distrib.toHasAdd.{u1} R (NonUnitalNonAssocSemiring.toDistrib.{u1} R (NonAssocSemiring.toNonUnitalNonAssocSemiring.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5)))) (Distrib.toHasMul.{u1} R (NonUnitalNonAssocSemiring.toDistrib.{u1} R (NonAssocSemiring.toNonUnitalNonAssocSemiring.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5)))) (Distrib.toHasAdd.{u1} R (NonUnitalNonAssocSemiring.toDistrib.{u1} R (NonAssocSemiring.toNonUnitalNonAssocSemiring.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5)))))
-but is expected to have type
-  forall (G : Type.{u2}) [_inst_3 : Group.{u2} G] (R : Type.{u1}) [_inst_5 : Semiring.{u1} R] [_inst_8 : MulSemiringAction.{u2, u1} G R (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_3)) _inst_5], G -> (RingEquiv.{u1, u1} R R (NonUnitalNonAssocSemiring.toMul.{u1} R (NonAssocSemiring.toNonUnitalNonAssocSemiring.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5))) (NonUnitalNonAssocSemiring.toMul.{u1} R (NonAssocSemiring.toNonUnitalNonAssocSemiring.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5))) (Distrib.toAdd.{u1} R (NonUnitalNonAssocSemiring.toDistrib.{u1} R (NonAssocSemiring.toNonUnitalNonAssocSemiring.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5)))) (Distrib.toAdd.{u1} R (NonUnitalNonAssocSemiring.toDistrib.{u1} R (NonAssocSemiring.toNonUnitalNonAssocSemiring.{u1} R (Semiring.toNonAssocSemiring.{u1} R _inst_5)))))
-Case conversion may be inaccurate. Consider using '#align mul_semiring_action.to_ring_equiv MulSemiringAction.toRingEquivₓ'. -/
 /-- Each element of the group defines a semiring isomorphism. -/
 @[simps]
 def MulSemiringAction.toRingEquiv [MulSemiringAction G R] (x : G) : R ≃+* R :=
@@ -114,12 +102,6 @@ variable {M G A R F}
 
 attribute [simp] smul_one smul_mul' smul_zero smul_add
 
-/- warning: smul_inv'' -> smul_inv'' is a dubious translation:
-lean 3 declaration is
-  forall {M : Type.{u2}} [_inst_1 : Monoid.{u2} M] {F : Type.{u1}} [_inst_7 : DivisionRing.{u1} F] [_inst_8 : MulSemiringAction.{u2, u1} M F _inst_1 (Ring.toSemiring.{u1} F (DivisionRing.toRing.{u1} F _inst_7))] (x : M) (m : F), Eq.{succ u1} F (SMul.smul.{u2, u1} M F (SMulZeroClass.toHasSmul.{u2, u1} M F (AddZeroClass.toHasZero.{u1} F (AddMonoid.toAddZeroClass.{u1} F (AddMonoidWithOne.toAddMonoid.{u1} F (AddCommMonoidWithOne.toAddMonoidWithOne.{u1} F (NonAssocSemiring.toAddCommMonoidWithOne.{u1} F (Semiring.toNonAssocSemiring.{u1} F (Ring.toSemiring.{u1} F (DivisionRing.toRing.{u1} F _inst_7)))))))) (DistribSMul.toSmulZeroClass.{u2, u1} M F (AddMonoid.toAddZeroClass.{u1} F (AddMonoidWithOne.toAddMonoid.{u1} F (AddCommMonoidWithOne.toAddMonoidWithOne.{u1} F (NonAssocSemiring.toAddCommMonoidWithOne.{u1} F (Semiring.toNonAssocSemiring.{u1} F (Ring.toSemiring.{u1} F (DivisionRing.toRing.{u1} F _inst_7))))))) (DistribMulAction.toDistribSMul.{u2, u1} M F _inst_1 (AddMonoidWithOne.toAddMonoid.{u1} F (AddCommMonoidWithOne.toAddMonoidWithOne.{u1} F (NonAssocSemiring.toAddCommMonoidWithOne.{u1} F (Semiring.toNonAssocSemiring.{u1} F (Ring.toSemiring.{u1} F (DivisionRing.toRing.{u1} F _inst_7)))))) (MulSemiringAction.toDistribMulAction.{u2, u1} M F _inst_1 (Ring.toSemiring.{u1} F (DivisionRing.toRing.{u1} F _inst_7)) _inst_8)))) x (Inv.inv.{u1} F (DivInvMonoid.toHasInv.{u1} F (DivisionRing.toDivInvMonoid.{u1} F _inst_7)) m)) (Inv.inv.{u1} F (DivInvMonoid.toHasInv.{u1} F (DivisionRing.toDivInvMonoid.{u1} F _inst_7)) (SMul.smul.{u2, u1} M F (SMulZeroClass.toHasSmul.{u2, u1} M F (AddZeroClass.toHasZero.{u1} F (AddMonoid.toAddZeroClass.{u1} F (AddMonoidWithOne.toAddMonoid.{u1} F (AddCommMonoidWithOne.toAddMonoidWithOne.{u1} F (NonAssocSemiring.toAddCommMonoidWithOne.{u1} F (Semiring.toNonAssocSemiring.{u1} F (Ring.toSemiring.{u1} F (DivisionRing.toRing.{u1} F _inst_7)))))))) (DistribSMul.toSmulZeroClass.{u2, u1} M F (AddMonoid.toAddZeroClass.{u1} F (AddMonoidWithOne.toAddMonoid.{u1} F (AddCommMonoidWithOne.toAddMonoidWithOne.{u1} F (NonAssocSemiring.toAddCommMonoidWithOne.{u1} F (Semiring.toNonAssocSemiring.{u1} F (Ring.toSemiring.{u1} F (DivisionRing.toRing.{u1} F _inst_7))))))) (DistribMulAction.toDistribSMul.{u2, u1} M F _inst_1 (AddMonoidWithOne.toAddMonoid.{u1} F (AddCommMonoidWithOne.toAddMonoidWithOne.{u1} F (NonAssocSemiring.toAddCommMonoidWithOne.{u1} F (Semiring.toNonAssocSemiring.{u1} F (Ring.toSemiring.{u1} F (DivisionRing.toRing.{u1} F _inst_7)))))) (MulSemiringAction.toDistribMulAction.{u2, u1} M F _inst_1 (Ring.toSemiring.{u1} F (DivisionRing.toRing.{u1} F _inst_7)) _inst_8)))) x m))
-but is expected to have type
-  forall {M : Type.{u1}} [_inst_1 : Monoid.{u1} M] {F : Type.{u2}} [_inst_7 : DivisionRing.{u2} F] [_inst_8 : MulSemiringAction.{u1, u2} M F _inst_1 (DivisionSemiring.toSemiring.{u2} F (DivisionRing.toDivisionSemiring.{u2} F _inst_7))] (x : M) (m : F), Eq.{succ u2} F (HSMul.hSMul.{u1, u2, u2} M F F (instHSMul.{u1, u2} M F (SMulZeroClass.toSMul.{u1, u2} M F (MonoidWithZero.toZero.{u2} F (Semiring.toMonoidWithZero.{u2} F (DivisionSemiring.toSemiring.{u2} F (DivisionRing.toDivisionSemiring.{u2} F _inst_7)))) (DistribSMul.toSMulZeroClass.{u1, u2} M F (AddMonoid.toAddZeroClass.{u2} F (AddMonoidWithOne.toAddMonoid.{u2} F (AddGroupWithOne.toAddMonoidWithOne.{u2} F (Ring.toAddGroupWithOne.{u2} F (DivisionRing.toRing.{u2} F _inst_7))))) (DistribMulAction.toDistribSMul.{u1, u2} M F _inst_1 (AddMonoidWithOne.toAddMonoid.{u2} F (AddGroupWithOne.toAddMonoidWithOne.{u2} F (Ring.toAddGroupWithOne.{u2} F (DivisionRing.toRing.{u2} F _inst_7)))) (MulSemiringAction.toDistribMulAction.{u1, u2} M F _inst_1 (Ring.toSemiring.{u2} F (DivisionRing.toRing.{u2} F _inst_7)) _inst_8))))) x (Inv.inv.{u2} F (DivisionRing.toInv.{u2} F _inst_7) m)) (Inv.inv.{u2} F (DivisionRing.toInv.{u2} F _inst_7) (HSMul.hSMul.{u1, u2, u2} M F F (instHSMul.{u1, u2} M F (SMulZeroClass.toSMul.{u1, u2} M F (MonoidWithZero.toZero.{u2} F (Semiring.toMonoidWithZero.{u2} F (DivisionSemiring.toSemiring.{u2} F (DivisionRing.toDivisionSemiring.{u2} F _inst_7)))) (DistribSMul.toSMulZeroClass.{u1, u2} M F (AddMonoid.toAddZeroClass.{u2} F (AddMonoidWithOne.toAddMonoid.{u2} F (AddGroupWithOne.toAddMonoidWithOne.{u2} F (Ring.toAddGroupWithOne.{u2} F (DivisionRing.toRing.{u2} F _inst_7))))) (DistribMulAction.toDistribSMul.{u1, u2} M F _inst_1 (AddMonoidWithOne.toAddMonoid.{u2} F (AddGroupWithOne.toAddMonoidWithOne.{u2} F (Ring.toAddGroupWithOne.{u2} F (DivisionRing.toRing.{u2} F _inst_7)))) (MulSemiringAction.toDistribMulAction.{u1, u2} M F _inst_1 (Ring.toSemiring.{u2} F (DivisionRing.toRing.{u2} F _inst_7)) _inst_8))))) x m))
-Case conversion may be inaccurate. Consider using '#align smul_inv'' smul_inv''ₓ'. -/
 /-- Note that `smul_inv'` refers to the group case, and `smul_inv` has an additional inverse
 on `x`. -/
 @[simp]

c3291da4

bump to nightly-2023-02-21-16

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

1107b979

Changes in mathlib4

mathlib3

mathlib4

207cfac9

chore: don't import Field in Algebra.Ring.Equiv (#11881)

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

d5a796bf

Diff

@@ -6,6 +6,7 @@ Authors: Kenny Lau
 import Mathlib.Algebra.GroupWithZero.Units.Lemmas
 import Mathlib.Algebra.Ring.Equiv
 import Mathlib.GroupTheory.GroupAction.Group
+import Mathlib.Algebra.Field.Defs
 
 #align_import algebra.group_ring_action.basic from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432"
 
@@ -45,7 +46,7 @@ class MulSemiringAction (M : Type u) (R : Type v) [Monoid M] [Semiring R] extend
 section Semiring
 
 variable (M N G : Type*) [Monoid M] [Monoid N] [Group G]
-variable (A R S F : Type v) [AddMonoid A] [Semiring R] [CommSemiring S] [DivisionRing F]
+variable (A R S F : Type v) [AddMonoid A] [Semiring R] [CommSemiring S]
 
 -- note we could not use `extends` since these typeclasses are made with `old_structure_cmd`
 instance (priority := 100) MulSemiringAction.toMulDistribMulAction [h : MulSemiringAction M R] :
@@ -115,6 +116,8 @@ variable {M G A R F}
 
 attribute [simp] smul_one smul_mul' smul_zero smul_add
 
+variable [DivisionRing F]
+
 /-- Note that `smul_inv'` refers to the group case, and `smul_inv` has an additional inverse
 on `x`. -/
 @[simp]

207cfac9

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

@@ -45,7 +45,6 @@ class MulSemiringAction (M : Type u) (R : Type v) [Monoid M] [Semiring R] extend
 section Semiring
 
 variable (M N G : Type*) [Monoid M] [Monoid N] [Group G]
-
 variable (A R S F : Type v) [AddMonoid A] [Semiring R] [CommSemiring S] [DivisionRing F]
 
 -- note we could not use `extends` since these typeclasses are made with `old_structure_cmd`

207cfac9

chore: remove duplicate instances (#10316)

These are a few places where duplicates of instances are in scope, eg variable {K : Type*} [Field K] ... theorem foo [Field K] .....

eb994467

Diff

@@ -69,7 +69,7 @@ theorem toRingHom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
 /-- The tautological action by `R →+* R` on `R`.
 
 This generalizes `Function.End.applyMulAction`. -/
-instance RingHom.applyMulSemiringAction [Semiring R] : MulSemiringAction (R →+* R) R where
+instance RingHom.applyMulSemiringAction : MulSemiringAction (R →+* R) R where
   smul := (· <| ·)
   smul_one := map_one
   smul_mul := map_mul
@@ -80,12 +80,12 @@ instance RingHom.applyMulSemiringAction [Semiring R] : MulSemiringAction (R →+
 #align ring_hom.apply_distrib_mul_action RingHom.applyMulSemiringActionₓ
 
 @[simp]
-protected theorem RingHom.smul_def [Semiring R] (f : R →+* R) (a : R) : f • a = f a :=
+protected theorem RingHom.smul_def (f : R →+* R) (a : R) : f • a = f a :=
   rfl
 #align ring_hom.smul_def RingHom.smul_def
 
 /-- `RingHom.applyMulSemiringAction` is faithful. -/
-instance RingHom.applyFaithfulSMul [Semiring R] : FaithfulSMul (R →+* R) R :=
+instance RingHom.applyFaithfulSMul : FaithfulSMul (R →+* R) R :=
   ⟨fun {_ _} h => RingHom.ext h⟩
 #align ring_hom.apply_has_faithful_smul RingHom.applyFaithfulSMul

207cfac9

chore: Move zpow lemmas (#9720)

These lemmas can be proved much earlier with little to no change to their proofs.

Part of #9411

1564a327

Diff

@@ -3,8 +3,8 @@ Copyright (c) 2020 Kenny Lau. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Kenny Lau
 -/
+import Mathlib.Algebra.GroupWithZero.Units.Lemmas
 import Mathlib.Algebra.Ring.Equiv
-import Mathlib.Algebra.Field.Defs
 import Mathlib.GroupTheory.GroupAction.Group
 
 #align_import algebra.group_ring_action.basic from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432"

207cfac9

feat(Algebra/GroupRingAction/Basic): RingHom application forms a MulDistribMulAction (#8396)

This replaces a previous weaker result that it formed a DistribMulAction.

The docstring seemed to assume this already existed, but forgot to mention the RingAut version in another file.

29bc69ac

Diff

@@ -66,6 +66,29 @@ theorem toRingHom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
   eq_of_smul_eq_smul fun r => RingHom.ext_iff.1 h r
 #align to_ring_hom_injective toRingHom_injective
 
+/-- The tautological action by `R →+* R` on `R`.
+
+This generalizes `Function.End.applyMulAction`. -/
+instance RingHom.applyMulSemiringAction [Semiring R] : MulSemiringAction (R →+* R) R where
+  smul := (· <| ·)
+  smul_one := map_one
+  smul_mul := map_mul
+  smul_zero := RingHom.map_zero
+  smul_add := RingHom.map_add
+  one_smul _ := rfl
+  mul_smul _ _ _ := rfl
+#align ring_hom.apply_distrib_mul_action RingHom.applyMulSemiringActionₓ
+
+@[simp]
+protected theorem RingHom.smul_def [Semiring R] (f : R →+* R) (a : R) : f • a = f a :=
+  rfl
+#align ring_hom.smul_def RingHom.smul_def
+
+/-- `RingHom.applyMulSemiringAction` is faithful. -/
+instance RingHom.applyFaithfulSMul [Semiring R] : FaithfulSMul (R →+* R) R :=
+  ⟨fun {_ _} h => RingHom.ext h⟩
+#align ring_hom.apply_has_faithful_smul RingHom.applyFaithfulSMul
+
 /-- Each element of the group defines a semiring isomorphism. -/
 @[simps!]
 def MulSemiringAction.toRingEquiv [MulSemiringAction G R] (x : G) : R ≃+* R :=

207cfac9

perf: remove overspecified fields (#6965)

This removes redundant field values of the form add := add for smaller terms and less unfolding during unification.

A list of all files containing a structure instance of the form { a1, ... with x1 := val, ... } where some xi is a field of some aj was generated by modifying the structure instance elaboration algorithm to print such overlaps to stdout in a custom toolchain.

Using that toolchain, I went through each file on the list and attempted to remove algebraic fields that overlapped and were redundant, eg add := add and not toFun (though some other ones did creep in). If things broke (which was the case in a couple of cases), I did not push further and reverted.

It is possible that pushing harder and trying to remove all redundant overlaps will yield further improvements.

12150475

Diff

@@ -82,7 +82,7 @@ variable {M N}
 See note [reducible non-instances]. -/
 @[reducible]
 def MulSemiringAction.compHom (f : N →* M) [MulSemiringAction M R] : MulSemiringAction N R :=
-  { DistribMulAction.compHom R f, MulDistribMulAction.compHom R f with smul := SMul.comp.smul f }
+  { DistribMulAction.compHom R f, MulDistribMulAction.compHom R f with }
 #align mul_semiring_action.comp_hom MulSemiringAction.compHom
 
 end

207cfac9

chore: banish Type _ and Sort _ (#6499)

We remove all possible occurences of Type _ and Sort _ in favor of Type* and Sort*.

This has nice performance benefits.

32de3f67

Diff

@@ -44,7 +44,7 @@ class MulSemiringAction (M : Type u) (R : Type v) [Monoid M] [Semiring R] extend
 
 section Semiring
 
-variable (M N G : Type _) [Monoid M] [Monoid N] [Group G]
+variable (M N G : Type*) [Monoid M] [Monoid N] [Group G]
 
 variable (A R S F : Type v) [AddMonoid A] [Semiring R] [CommSemiring S] [DivisionRing F]

207cfac9

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

@@ -2,16 +2,13 @@
 Copyright (c) 2020 Kenny Lau. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Kenny Lau
-
-! This file was ported from Lean 3 source module algebra.group_ring_action.basic
-! leanprover-community/mathlib commit 207cfac9fcd06138865b5d04f7091e46d9320432
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathlib.Algebra.Ring.Equiv
 import Mathlib.Algebra.Field.Defs
 import Mathlib.GroupTheory.GroupAction.Group
 
+#align_import algebra.group_ring_action.basic from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432"
+
 /-!
 # Group action on rings

207cfac9

chore: fix many typos (#4967)

These are all doc fixes

6f9e51c3

Diff

@@ -41,7 +41,7 @@ class MulSemiringAction (M : Type u) (R : Type v) [Monoid M] [Semiring R] extend
   DistribMulAction M R where
   /-- Multipliying `1` by a scalar gives `1` -/
   smul_one : ∀ g : M, (g • (1 : R) : R) = 1
-  /-- Scalara multiplication distributes across multiplication -/
+  /-- Scalar multiplication distributes across multiplication -/
   smul_mul : ∀ (g : M) (x y : R), g • (x * y) = g • x * g • y
 #align mul_semiring_action MulSemiringAction

207cfac9

fix: replace symmApply by symm_apply (#2560)

9aade17b

Diff

@@ -74,7 +74,7 @@ theorem toRingHom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
 def MulSemiringAction.toRingEquiv [MulSemiringAction G R] (x : G) : R ≃+* R :=
   { DistribMulAction.toAddEquiv R x, MulSemiringAction.toRingHom G R x with }
 #align mul_semiring_action.to_ring_equiv MulSemiringAction.toRingEquiv
-#align mul_semiring_action.to_ring_equiv_symm_apply MulSemiringAction.toRingEquiv_symmApply
+#align mul_semiring_action.to_ring_equiv_symm_apply MulSemiringAction.toRingEquiv_symm_apply
 #align mul_semiring_action.to_ring_equiv_apply MulSemiringAction.toRingEquiv_apply
 
 section

207cfac9

feat: require @[simps!] if simps runs in expensive mode (#1885)

This does not change the behavior of simps, just raises a linter error if you run simps in a more expensive mode without writing !.
Fixed some incorrect occurrences of to_additive, simps. Will do that systematically in future PR.
Fix port of OmegaCompletePartialOrder.ContinuousHom.ofMono a bit

Co-authored-by: Yury G. Kudryashov <urkud@urkud.name>

52c04a34

Diff

@@ -58,7 +58,7 @@ instance (priority := 100) MulSemiringAction.toMulDistribMulAction [h : MulSemir
 #align mul_semiring_action.to_mul_distrib_mul_action MulSemiringAction.toMulDistribMulAction
 
 /-- Each element of the monoid defines a semiring homomorphism. -/
-@[simps]
+@[simps!]
 def MulSemiringAction.toRingHom [MulSemiringAction M R] (x : M) : R →+* R :=
   { MulDistribMulAction.toMonoidHom R x, DistribMulAction.toAddMonoidHom R x with }
 #align mul_semiring_action.to_ring_hom MulSemiringAction.toRingHom
@@ -70,7 +70,7 @@ theorem toRingHom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
 #align to_ring_hom_injective toRingHom_injective
 
 /-- Each element of the group defines a semiring isomorphism. -/
-@[simps]
+@[simps!]
 def MulSemiringAction.toRingEquiv [MulSemiringAction G R] (x : G) : R ≃+* R :=
   { DistribMulAction.toAddEquiv R x, MulSemiringAction.toRingHom G R x with }
 #align mul_semiring_action.to_ring_equiv MulSemiringAction.toRingEquiv

207cfac9

chore: add missing #align statements (#1902)

This PR is the result of a slight variant on the following "algorithm"

take all mathlib 3 names, remove _ and make all uppercase letters into lowercase
take all mathlib 4 names, remove _ and make all uppercase letters into lowercase
look for matches, and create pairs (original_lean3_name, OriginalLean4Name)
for pairs that do not have an align statement:
- use Lean 4 to lookup the file + position of the Lean 4 name
- add an #align statement just before the next empty line
manually fix some tiny mistakes (e.g., empty lines in proofs might cause the #align statement to have been inserted too early)

b72bb858

Diff

@@ -62,6 +62,7 @@ instance (priority := 100) MulSemiringAction.toMulDistribMulAction [h : MulSemir
 def MulSemiringAction.toRingHom [MulSemiringAction M R] (x : M) : R →+* R :=
   { MulDistribMulAction.toMonoidHom R x, DistribMulAction.toAddMonoidHom R x with }
 #align mul_semiring_action.to_ring_hom MulSemiringAction.toRingHom
+#align mul_semiring_action.to_ring_hom_apply MulSemiringAction.toRingHom_apply
 
 theorem toRingHom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
     Function.Injective (MulSemiringAction.toRingHom M R) := fun _ _ h =>
@@ -73,6 +74,8 @@ theorem toRingHom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
 def MulSemiringAction.toRingEquiv [MulSemiringAction G R] (x : G) : R ≃+* R :=
   { DistribMulAction.toAddEquiv R x, MulSemiringAction.toRingHom G R x with }
 #align mul_semiring_action.to_ring_equiv MulSemiringAction.toRingEquiv
+#align mul_semiring_action.to_ring_equiv_symm_apply MulSemiringAction.toRingEquiv_symmApply
+#align mul_semiring_action.to_ring_equiv_apply MulSemiringAction.toRingEquiv_apply
 
 section

207cfac9

chore: tidy various files (#1247)

Co-authored-by: ChrisHughes24 <chrishughes24@gmail.com>

0690e5fb

Diff

@@ -63,10 +63,10 @@ def MulSemiringAction.toRingHom [MulSemiringAction M R] (x : M) : R →+* R :=
   { MulDistribMulAction.toMonoidHom R x, DistribMulAction.toAddMonoidHom R x with }
 #align mul_semiring_action.to_ring_hom MulSemiringAction.toRingHom
 
-theorem to_ring_hom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
+theorem toRingHom_injective [MulSemiringAction M R] [FaithfulSMul M R] :
     Function.Injective (MulSemiringAction.toRingHom M R) := fun _ _ h =>
   eq_of_smul_eq_smul fun r => RingHom.ext_iff.1 h r
-#align to_ring_hom_injective to_ring_hom_injective
+#align to_ring_hom_injective toRingHom_injective
 
 /-- Each element of the group defines a semiring isomorphism. -/
 @[simps]
@@ -78,7 +78,7 @@ section
 
 variable {M N}
 
-/-- Compose a `mul_semiring_action` with a `monoid_hom`, with action `f r' • m`.
+/-- Compose a `MulSemiringAction` with a `MonoidHom`, with action `f r' • m`.
 See note [reducible non-instances]. -/
 @[reducible]
 def MulSemiringAction.compHom (f : N →* M) [MulSemiringAction M R] : MulSemiringAction N R :=

207cfac9

feat port: Algebra.GroupRingAction.Basic (#1225)

Easy

b06cedfb

207cfac9

initial commit

741d8e52