data.finsupp.indicator | 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

842328d9

(last sync)

feat(data/finsupp/indicator, algebra/big_operators/finsupp): add some lemmas about finsupp.indicator (#17413)

mathlib4 PR: https://github.com/leanprover-community/mathlib4/pull/2258

Diff

@@ -66,4 +66,8 @@ begin
   exact hi (indicator_of_not_mem h _),
 end
 
+lemma single_eq_indicator (i : ι) (b : α) :
+  single i b = indicator {i} (λ _ _, b) :=
+by { classical, ext, simp [single_apply, indicator_apply, @eq_comm _ a] }
+
 end finsupp

f7fc89d5

(first ported)

Changes in mathlib3port

mathlib3

mathlib3port

842328d9

bump to nightly-2024-03-17-08

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

22f01ce4

Diff

@@ -85,7 +85,7 @@ theorem indicator_injective : Injective fun f : ∀ i ∈ s, α => indicator s f
 theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
   by
   intro i hi
-  rw [mem_coe, mem_support_iff] at hi 
+  rw [mem_coe, mem_support_iff] at hi
   by_contra
   exact hi (indicator_of_not_mem h _)
 #align finsupp.support_indicator_subset Finsupp.support_indicator_subset

842328d9

bump to nightly-2024-02-01-06

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

5433bded

Diff

@@ -94,6 +94,8 @@ theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
 #print Finsupp.single_eq_indicator /-
 theorem single_eq_indicator (i : ι) (b : α) : single i b = indicator {i} fun _ _ => b := by
   classical
+  ext
+  simp [single_apply, indicator_apply, @eq_comm _ a]
 #align finsupp.single_eq_indicator Finsupp.single_eq_indicator
 -/

842328d9

bump to nightly-2024-01-31-06

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

61100fe9

Diff

@@ -94,8 +94,6 @@ theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
 #print Finsupp.single_eq_indicator /-
 theorem single_eq_indicator (i : ι) (b : α) : single i b = indicator {i} fun _ _ => b := by
   classical
-  ext
-  simp [single_apply, indicator_apply, @eq_comm _ a]
 #align finsupp.single_eq_indicator Finsupp.single_eq_indicator
 -/

842328d9

bump to nightly-2023-09-24-06

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

5655435f

Diff

@@ -3,7 +3,7 @@ Copyright (c) 2022 Yaël Dillies. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Yaël Dillies
 -/
-import Mathbin.Data.Finsupp.Defs
+import Data.Finsupp.Defs
 
 #align_import data.finsupp.indicator from "leanprover-community/mathlib"@"842328d9df7e96fd90fc424e115679c15fb23a71"

842328d9

bump to nightly-2023-07-20-09

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

9c56d0dd

Diff

@@ -2,14 +2,11 @@
 Copyright (c) 2022 Yaël Dillies. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Yaël Dillies
-
-! This file was ported from Lean 3 source module data.finsupp.indicator
-! leanprover-community/mathlib commit 842328d9df7e96fd90fc424e115679c15fb23a71
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathbin.Data.Finsupp.Defs
 
+#align_import data.finsupp.indicator from "leanprover-community/mathlib"@"842328d9df7e96fd90fc424e115679c15fb23a71"
+
 /-!
 # Building finitely supported functions off finsets

842328d9

bump to nightly-2023-06-20-01

mathlib commit https://github.com/leanprover-community/mathlib/commit/2a0ce625dbb0ffbc7d1316597de0b25c1ec75303

9b351f8c

Diff

@@ -78,7 +78,7 @@ theorem indicator_apply [DecidableEq ι] : indicator s f i = if hi : i ∈ s the
 theorem indicator_injective : Injective fun f : ∀ i ∈ s, α => indicator s f :=
   by
   intro a b h
-  ext (i hi)
+  ext i hi
   rw [← indicator_of_mem hi a, ← indicator_of_mem hi b]
   exact congr_fun h i
 #align finsupp.indicator_injective Finsupp.indicator_injective

842328d9

bump to nightly-2023-06-13-21

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

829520ac

Diff

@@ -53,21 +53,28 @@ def indicator (s : Finset ι) (f : ∀ i ∈ s, α) : ι →₀ α
 #align finsupp.indicator Finsupp.indicator
 -/
 
+#print Finsupp.indicator_of_mem /-
 theorem indicator_of_mem (hi : i ∈ s) (f : ∀ i ∈ s, α) : indicator s f i = f i hi :=
   @dif_pos _ (id _) hi _ _ _
 #align finsupp.indicator_of_mem Finsupp.indicator_of_mem
+-/
 
+#print Finsupp.indicator_of_not_mem /-
 theorem indicator_of_not_mem (hi : i ∉ s) (f : ∀ i ∈ s, α) : indicator s f i = 0 :=
   @dif_neg _ (id _) hi _ _ _
 #align finsupp.indicator_of_not_mem Finsupp.indicator_of_not_mem
+-/
 
 variable (s i)
 
+#print Finsupp.indicator_apply /-
 @[simp]
 theorem indicator_apply [DecidableEq ι] : indicator s f i = if hi : i ∈ s then f i hi else 0 := by
   convert rfl
 #align finsupp.indicator_apply Finsupp.indicator_apply
+-/
 
+#print Finsupp.indicator_injective /-
 theorem indicator_injective : Injective fun f : ∀ i ∈ s, α => indicator s f :=
   by
   intro a b h
@@ -75,7 +82,9 @@ theorem indicator_injective : Injective fun f : ∀ i ∈ s, α => indicator s f
   rw [← indicator_of_mem hi a, ← indicator_of_mem hi b]
   exact congr_fun h i
 #align finsupp.indicator_injective Finsupp.indicator_injective
+-/
 
+#print Finsupp.support_indicator_subset /-
 theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
   by
   intro i hi
@@ -83,12 +92,15 @@ theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
   by_contra
   exact hi (indicator_of_not_mem h _)
 #align finsupp.support_indicator_subset Finsupp.support_indicator_subset
+-/
 
+#print Finsupp.single_eq_indicator /-
 theorem single_eq_indicator (i : ι) (b : α) : single i b = indicator {i} fun _ _ => b := by
   classical
   ext
   simp [single_apply, indicator_apply, @eq_comm _ a]
 #align finsupp.single_eq_indicator Finsupp.single_eq_indicator
+-/
 
 end Finsupp

842328d9

bump to nightly-2023-06-04-18

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

3fb4268b

Diff

@@ -86,8 +86,8 @@ theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
 
 theorem single_eq_indicator (i : ι) (b : α) : single i b = indicator {i} fun _ _ => b := by
   classical
-    ext
-    simp [single_apply, indicator_apply, @eq_comm _ a]
+  ext
+  simp [single_apply, indicator_apply, @eq_comm _ a]
 #align finsupp.single_eq_indicator Finsupp.single_eq_indicator
 
 end Finsupp

842328d9

bump to nightly-2023-06-01-16

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

b9c87c70

Diff

@@ -79,7 +79,7 @@ theorem indicator_injective : Injective fun f : ∀ i ∈ s, α => indicator s f
 theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
   by
   intro i hi
-  rw [mem_coe, mem_support_iff] at hi
+  rw [mem_coe, mem_support_iff] at hi 
   by_contra
   exact hi (indicator_of_not_mem h _)
 #align finsupp.support_indicator_subset Finsupp.support_indicator_subset

842328d9

bump to nightly-2023-05-28-06

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

ba5d8b97

Diff

@@ -53,45 +53,21 @@ def indicator (s : Finset ι) (f : ∀ i ∈ s, α) : ι →₀ α
 #align finsupp.indicator Finsupp.indicator
 -/
 
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-Case conversion may be inaccurate. Consider using '#align finsupp.indicator_of_mem Finsupp.indicator_of_memₓ'. -/
 theorem indicator_of_mem (hi : i ∈ s) (f : ∀ i ∈ s, α) : indicator s f i = f i hi :=
   @dif_pos _ (id _) hi _ _ _
 #align finsupp.indicator_of_mem Finsupp.indicator_of_mem
 
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 theorem indicator_of_not_mem (hi : i ∉ s) (f : ∀ i ∈ s, α) : indicator s f i = 0 :=
   @dif_neg _ (id _) hi _ _ _
 #align finsupp.indicator_of_not_mem Finsupp.indicator_of_not_mem
 
 variable (s i)
 
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 @[simp]
 theorem indicator_apply [DecidableEq ι] : indicator s f i = if hi : i ∈ s then f i hi else 0 := by
   convert rfl
 #align finsupp.indicator_apply Finsupp.indicator_apply
 
-/- warning: finsupp.indicator_injective -> Finsupp.indicator_injective is a dubious translation:
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 theorem indicator_injective : Injective fun f : ∀ i ∈ s, α => indicator s f :=
   by
   intro a b h
@@ -100,12 +76,6 @@ theorem indicator_injective : Injective fun f : ∀ i ∈ s, α => indicator s f
   exact congr_fun h i
 #align finsupp.indicator_injective Finsupp.indicator_injective
 
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-Case conversion may be inaccurate. Consider using '#align finsupp.support_indicator_subset Finsupp.support_indicator_subsetₓ'. -/
 theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
   by
   intro i hi
@@ -114,12 +84,6 @@ theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
   exact hi (indicator_of_not_mem h _)
 #align finsupp.support_indicator_subset Finsupp.support_indicator_subset
 
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-  forall {ι : Type.{u2}} {α : Type.{u1}} [_inst_1 : Zero.{u1} α] (i : ι) (b : α), Eq.{max (succ u2) (succ u1)} (Finsupp.{u2, u1} ι α _inst_1) (Finsupp.single.{u2, u1} ι α _inst_1 i b) (Finsupp.indicator.{u2, u1} ι α _inst_1 (Singleton.singleton.{u2, u2} ι (Finset.{u2} ι) (Finset.instSingletonFinset.{u2} ι) i) (fun (_x : ι) (_x : Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) _x (Singleton.singleton.{u2, u2} ι (Finset.{u2} ι) (Finset.instSingletonFinset.{u2} ι) i)) => b))
-Case conversion may be inaccurate. Consider using '#align finsupp.single_eq_indicator Finsupp.single_eq_indicatorₓ'. -/
 theorem single_eq_indicator (i : ι) (b : α) : single i b = indicator {i} fun _ _ => b := by
   classical
     ext

842328d9

bump to nightly-2023-03-21-00

mathlib commit https://github.com/leanprover-community/mathlib/commit/7ec294687917cbc5c73620b4414ae9b5dd9ae1b4

323f76e6

Diff

@@ -118,7 +118,7 @@ theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
 lean 3 declaration is
   forall {ι : Type.{u1}} {α : Type.{u2}} [_inst_1 : Zero.{u2} α] (i : ι) (b : α), Eq.{max (succ u1) (succ u2)} (Finsupp.{u1, u2} ι α _inst_1) (Finsupp.single.{u1, u2} ι α _inst_1 i b) (Finsupp.indicator.{u1, u2} ι α _inst_1 (Singleton.singleton.{u1, u1} ι (Finset.{u1} ι) (Finset.hasSingleton.{u1} ι) i) (fun (_x : ι) (_x : Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) _x (Singleton.singleton.{u1, u1} ι (Finset.{u1} ι) (Finset.hasSingleton.{u1} ι) i)) => b))
 but is expected to have type
-  forall {ι : Type.{u2}} {α : Type.{u1}} [_inst_1 : Zero.{u1} α] {i : ι} {b : α}, Eq.{max (succ u2) (succ u1)} (forall (a : ι), (fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) a) (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (Finsupp.{u2, u1} ι α _inst_1) ι (fun (a : ι) => (fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) a) (Finsupp.funLike.{u2, u1} ι α _inst_1) (Finsupp.single.{u2, u1} ι α _inst_1 i b)) (Set.indicator.{u2, u1} ι α _inst_1 (Singleton.singleton.{u2, u2} ι (Set.{u2} ι) (Set.instSingletonSet.{u2} ι) i) (fun (_x : ι) => b))
+  forall {ι : Type.{u2}} {α : Type.{u1}} [_inst_1 : Zero.{u1} α] (i : ι) (b : α), Eq.{max (succ u2) (succ u1)} (Finsupp.{u2, u1} ι α _inst_1) (Finsupp.single.{u2, u1} ι α _inst_1 i b) (Finsupp.indicator.{u2, u1} ι α _inst_1 (Singleton.singleton.{u2, u2} ι (Finset.{u2} ι) (Finset.instSingletonFinset.{u2} ι) i) (fun (_x : ι) (_x : Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) _x (Singleton.singleton.{u2, u2} ι (Finset.{u2} ι) (Finset.instSingletonFinset.{u2} ι) i)) => b))
 Case conversion may be inaccurate. Consider using '#align finsupp.single_eq_indicator Finsupp.single_eq_indicatorₓ'. -/
 theorem single_eq_indicator (i : ι) (b : α) : single i b = indicator {i} fun _ _ => b := by
   classical

842328d9

bump to nightly-2023-03-04-12

mathlib commit https://github.com/leanprover-community/mathlib/commit/62e8311c791f02c47451bf14aa2501048e7c2f33

726b2da6

Diff

@@ -55,7 +55,7 @@ def indicator (s : Finset ι) (f : ∀ i ∈ s, α) : ι →₀ α
 
 /- warning: finsupp.indicator_of_mem -> Finsupp.indicator_of_mem is a dubious translation:
 lean 3 declaration is
-  forall {ι : Type.{u1}} {α : Type.{u2}} [_inst_1 : Zero.{u2} α] {s : Finset.{u1} ι} {i : ι} (hi : Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) (f : forall (i : ι), (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) -> α), Eq.{succ u2} α (coeFn.{max (succ u1) (succ u2), max (succ u1) (succ u2)} (Finsupp.{u1, u2} ι α _inst_1) (fun (_x : Finsupp.{u1, u2} ι α _inst_1) => ι -> α) (Finsupp.hasCoeToFun.{u1, u2} ι α _inst_1) (Finsupp.indicator.{u1, u2} ι α _inst_1 s f) i) (f i hi)
+  forall {ι : Type.{u1}} {α : Type.{u2}} [_inst_1 : Zero.{u2} α] {s : Finset.{u1} ι} {i : ι} (hi : Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) (f : forall (i : ι), (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) -> α), Eq.{succ u2} α (coeFn.{max (succ u1) (succ u2), max (succ u1) (succ u2)} (Finsupp.{u1, u2} ι α _inst_1) (fun (_x : Finsupp.{u1, u2} ι α _inst_1) => ι -> α) (Finsupp.coeFun.{u1, u2} ι α _inst_1) (Finsupp.indicator.{u1, u2} ι α _inst_1 s f) i) (f i hi)
 but is expected to have type
   forall {ι : Type.{u2}} {α : Type.{u1}} [_inst_1 : Zero.{u1} α] {s : Finset.{u2} ι} {i : ι} (hi : Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) i s) (f : forall (i : ι), (Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) i s) -> α), Eq.{succ u1} ((fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) i) (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (Finsupp.{u2, u1} ι α _inst_1) ι (fun (_x : ι) => (fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) _x) (Finsupp.funLike.{u2, u1} ι α _inst_1) (Finsupp.indicator.{u2, u1} ι α _inst_1 s f) i) (f i hi)
 Case conversion may be inaccurate. Consider using '#align finsupp.indicator_of_mem Finsupp.indicator_of_memₓ'. -/
@@ -65,7 +65,7 @@ theorem indicator_of_mem (hi : i ∈ s) (f : ∀ i ∈ s, α) : indicator s f i
 
 /- warning: finsupp.indicator_of_not_mem -> Finsupp.indicator_of_not_mem is a dubious translation:
 lean 3 declaration is
-  forall {ι : Type.{u1}} {α : Type.{u2}} [_inst_1 : Zero.{u2} α] {s : Finset.{u1} ι} {i : ι}, (Not (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s)) -> (forall (f : forall (i : ι), (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) -> α), Eq.{succ u2} α (coeFn.{max (succ u1) (succ u2), max (succ u1) (succ u2)} (Finsupp.{u1, u2} ι α _inst_1) (fun (_x : Finsupp.{u1, u2} ι α _inst_1) => ι -> α) (Finsupp.hasCoeToFun.{u1, u2} ι α _inst_1) (Finsupp.indicator.{u1, u2} ι α _inst_1 s f) i) (OfNat.ofNat.{u2} α 0 (OfNat.mk.{u2} α 0 (Zero.zero.{u2} α _inst_1))))
+  forall {ι : Type.{u1}} {α : Type.{u2}} [_inst_1 : Zero.{u2} α] {s : Finset.{u1} ι} {i : ι}, (Not (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s)) -> (forall (f : forall (i : ι), (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) -> α), Eq.{succ u2} α (coeFn.{max (succ u1) (succ u2), max (succ u1) (succ u2)} (Finsupp.{u1, u2} ι α _inst_1) (fun (_x : Finsupp.{u1, u2} ι α _inst_1) => ι -> α) (Finsupp.coeFun.{u1, u2} ι α _inst_1) (Finsupp.indicator.{u1, u2} ι α _inst_1 s f) i) (OfNat.ofNat.{u2} α 0 (OfNat.mk.{u2} α 0 (Zero.zero.{u2} α _inst_1))))
 but is expected to have type
   forall {ι : Type.{u2}} {α : Type.{u1}} [_inst_1 : Zero.{u1} α] {s : Finset.{u2} ι} {i : ι}, (Not (Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) i s)) -> (forall (f : forall (i : ι), (Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) i s) -> α), Eq.{succ u1} ((fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) i) (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (Finsupp.{u2, u1} ι α _inst_1) ι (fun (_x : ι) => (fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) _x) (Finsupp.funLike.{u2, u1} ι α _inst_1) (Finsupp.indicator.{u2, u1} ι α _inst_1 s f) i) (OfNat.ofNat.{u1} ((fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) i) 0 (Zero.toOfNat0.{u1} ((fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) i) _inst_1)))
 Case conversion may be inaccurate. Consider using '#align finsupp.indicator_of_not_mem Finsupp.indicator_of_not_memₓ'. -/
@@ -77,7 +77,7 @@ variable (s i)
 
 /- warning: finsupp.indicator_apply -> Finsupp.indicator_apply is a dubious translation:
 lean 3 declaration is
-  forall {ι : Type.{u1}} {α : Type.{u2}} [_inst_1 : Zero.{u2} α] (s : Finset.{u1} ι) (f : forall (i : ι), (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) -> α) (i : ι) [_inst_2 : DecidableEq.{succ u1} ι], Eq.{succ u2} α (coeFn.{max (succ u1) (succ u2), max (succ u1) (succ u2)} (Finsupp.{u1, u2} ι α _inst_1) (fun (_x : Finsupp.{u1, u2} ι α _inst_1) => ι -> α) (Finsupp.hasCoeToFun.{u1, u2} ι α _inst_1) (Finsupp.indicator.{u1, u2} ι α _inst_1 s f) i) (dite.{succ u2} α (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) (Finset.decidableMem.{u1} ι (fun (a : ι) (b : ι) => _inst_2 a b) i s) (fun (hi : Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) => f i hi) (fun (hi : Not (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s)) => OfNat.ofNat.{u2} α 0 (OfNat.mk.{u2} α 0 (Zero.zero.{u2} α _inst_1))))
+  forall {ι : Type.{u1}} {α : Type.{u2}} [_inst_1 : Zero.{u2} α] (s : Finset.{u1} ι) (f : forall (i : ι), (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) -> α) (i : ι) [_inst_2 : DecidableEq.{succ u1} ι], Eq.{succ u2} α (coeFn.{max (succ u1) (succ u2), max (succ u1) (succ u2)} (Finsupp.{u1, u2} ι α _inst_1) (fun (_x : Finsupp.{u1, u2} ι α _inst_1) => ι -> α) (Finsupp.coeFun.{u1, u2} ι α _inst_1) (Finsupp.indicator.{u1, u2} ι α _inst_1 s f) i) (dite.{succ u2} α (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) (Finset.decidableMem.{u1} ι (fun (a : ι) (b : ι) => _inst_2 a b) i s) (fun (hi : Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s) => f i hi) (fun (hi : Not (Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) i s)) => OfNat.ofNat.{u2} α 0 (OfNat.mk.{u2} α 0 (Zero.zero.{u2} α _inst_1))))
 but is expected to have type
   forall {ι : Type.{u2}} {α : Type.{u1}} [_inst_1 : Zero.{u1} α] (s : Finset.{u2} ι) (f : forall (i : ι), (Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) i s) -> α) (i : ι) [_inst_2 : DecidableEq.{succ u2} ι], Eq.{succ u1} ((fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) i) (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (Finsupp.{u2, u1} ι α _inst_1) ι (fun (_x : ι) => (fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) _x) (Finsupp.funLike.{u2, u1} ι α _inst_1) (Finsupp.indicator.{u2, u1} ι α _inst_1 s f) i) (dite.{succ u1} α (Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) i s) (Finset.decidableMem.{u2} ι (fun (a : ι) (b : ι) => _inst_2 a b) i s) (fun (hi : Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) i s) => f i hi) (fun (hi : Not (Membership.mem.{u2, u2} ι (Finset.{u2} ι) (Finset.instMembershipFinset.{u2} ι) i s)) => OfNat.ofNat.{u1} α 0 (Zero.toOfNat0.{u1} α _inst_1)))
 Case conversion may be inaccurate. Consider using '#align finsupp.indicator_apply Finsupp.indicator_applyₓ'. -/

842328d9

bump to nightly-2023-03-03-22

mathlib commit https://github.com/leanprover-community/mathlib/commit/62e8311c791f02c47451bf14aa2501048e7c2f33

7fe4dd24

Diff

@@ -4,7 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Yaël Dillies
 
 ! This file was ported from Lean 3 source module data.finsupp.indicator
-! leanprover-community/mathlib commit 68d1483e8a718ec63219f0e227ca3f0140361086
+! leanprover-community/mathlib commit 842328d9df7e96fd90fc424e115679c15fb23a71
 ! Please do not edit these lines, except to modify the commit id
 ! if you have ported upstream changes.
 -/
@@ -114,5 +114,17 @@ theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s :=
   exact hi (indicator_of_not_mem h _)
 #align finsupp.support_indicator_subset Finsupp.support_indicator_subset
 
+/- warning: finsupp.single_eq_indicator -> Finsupp.single_eq_indicator is a dubious translation:
+lean 3 declaration is
+  forall {ι : Type.{u1}} {α : Type.{u2}} [_inst_1 : Zero.{u2} α] (i : ι) (b : α), Eq.{max (succ u1) (succ u2)} (Finsupp.{u1, u2} ι α _inst_1) (Finsupp.single.{u1, u2} ι α _inst_1 i b) (Finsupp.indicator.{u1, u2} ι α _inst_1 (Singleton.singleton.{u1, u1} ι (Finset.{u1} ι) (Finset.hasSingleton.{u1} ι) i) (fun (_x : ι) (_x : Membership.Mem.{u1, u1} ι (Finset.{u1} ι) (Finset.hasMem.{u1} ι) _x (Singleton.singleton.{u1, u1} ι (Finset.{u1} ι) (Finset.hasSingleton.{u1} ι) i)) => b))
+but is expected to have type
+  forall {ι : Type.{u2}} {α : Type.{u1}} [_inst_1 : Zero.{u1} α] {i : ι} {b : α}, Eq.{max (succ u2) (succ u1)} (forall (a : ι), (fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) a) (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (Finsupp.{u2, u1} ι α _inst_1) ι (fun (a : ι) => (fun (x._@.Mathlib.Data.Finsupp.Defs._hyg.779 : ι) => α) a) (Finsupp.funLike.{u2, u1} ι α _inst_1) (Finsupp.single.{u2, u1} ι α _inst_1 i b)) (Set.indicator.{u2, u1} ι α _inst_1 (Singleton.singleton.{u2, u2} ι (Set.{u2} ι) (Set.instSingletonSet.{u2} ι) i) (fun (_x : ι) => b))
+Case conversion may be inaccurate. Consider using '#align finsupp.single_eq_indicator Finsupp.single_eq_indicatorₓ'. -/
+theorem single_eq_indicator (i : ι) (b : α) : single i b = indicator {i} fun _ _ => b := by
+  classical
+    ext
+    simp [single_apply, indicator_apply, @eq_comm _ a]
+#align finsupp.single_eq_indicator Finsupp.single_eq_indicator
+
 end Finsupp

68d1483e

bump to nightly-2023-02-21-16

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

1107b979

Changes in mathlib4

mathlib3

mathlib4

842328d9

chore(*): rename FunLike to DFunLike (#9785)

This prepares for the introduction of a non-dependent synonym of FunLike, which helps a lot with keeping #8386 readable.

This is entirely search-and-replace in 680197f combined with manual fixes in 4145626, e900597 and b8428f8. The commands that generated this change:

sed -i 's/\bFunLike\b/DFunLike/g' {Archive,Counterexamples,Mathlib,test}/**/*.lean
sed -i 's/\btoFunLike\b/toDFunLike/g' {Archive,Counterexamples,Mathlib,test}/**/*.lean
sed -i 's/import Mathlib.Data.DFunLike/import Mathlib.Data.FunLike/g' {Archive,Counterexamples,Mathlib,test}/**/*.lean
sed -i 's/\bHom_FunLike\b/Hom_DFunLike/g' {Archive,Counterexamples,Mathlib,test}/**/*.lean     
sed -i 's/\binstFunLike\b/instDFunLike/g' {Archive,Counterexamples,Mathlib,test}/**/*.lean
sed -i 's/\bfunLike\b/instDFunLike/g' {Archive,Counterexamples,Mathlib,test}/**/*.lean
sed -i 's/\btoo many metavariables to apply `fun_like.has_coe_to_fun`/too many metavariables to apply `DFunLike.hasCoeToFun`/g' {Archive,Counterexamples,Mathlib,test}/**/*.lean

Co-authored-by: Anne Baanen <Vierkantor@users.noreply.github.com>

82656743

Diff

@@ -61,7 +61,7 @@ theorem indicator_injective : Injective fun f : ∀ i ∈ s, α => indicator s f
   intro a b h
   ext i hi
   rw [← indicator_of_mem hi a, ← indicator_of_mem hi b]
-  exact FunLike.congr_fun h i
+  exact DFunLike.congr_fun h i
 #align finsupp.indicator_injective Finsupp.indicator_injective
 
 theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s := by

842328d9

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

@@ -22,7 +22,7 @@ noncomputable section
 
 open Finset Function
 
-variable {ι α : Type _}
+variable {ι α : Type*}
 
 namespace Finsupp

842328d9

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

@@ -2,14 +2,11 @@
 Copyright (c) 2022 Yaël Dillies. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Yaël Dillies
-
-! This file was ported from Lean 3 source module data.finsupp.indicator
-! leanprover-community/mathlib commit 842328d9df7e96fd90fc424e115679c15fb23a71
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathlib.Data.Finsupp.Defs
 
+#align_import data.finsupp.indicator from "leanprover-community/mathlib"@"842328d9df7e96fd90fc424e115679c15fb23a71"
+
 /-!
 # Building finitely supported functions off finsets

842328d9

chore: remove superfluous parentheses in calls to ext (#5258)

Co-authored-by: Xavier Roblot <46200072+xroblot@users.noreply.github.com> Co-authored-by: Joël Riou <joel.riou@universite-paris-saclay.fr> Co-authored-by: Riccardo Brasca <riccardo.brasca@gmail.com> Co-authored-by: Yury G. Kudryashov <urkud@urkud.name> Co-authored-by: Scott Morrison <scott.morrison@anu.edu.au> Co-authored-by: Scott Morrison <scott.morrison@gmail.com> Co-authored-by: Jeremy Tan Jie Rui <reddeloostw@gmail.com> Co-authored-by: Pol'tta / Miyahara Kō <pol_tta@outlook.jp> Co-authored-by: Jason Yuen <jason_yuen2007@hotmail.com> Co-authored-by: Mario Carneiro <di.gama@gmail.com> Co-authored-by: Jireh Loreaux <loreaujy@gmail.com> Co-authored-by: Ruben Van de Velde <65514131+Ruben-VandeVelde@users.noreply.github.com> Co-authored-by: Kyle Miller <kmill31415@gmail.com> Co-authored-by: Heather Macbeth <25316162+hrmacbeth@users.noreply.github.com> Co-authored-by: Jujian Zhang <jujian.zhang1998@outlook.com> Co-authored-by: Yaël Dillies <yael.dillies@gmail.com>

3d6731dc

Diff

@@ -62,7 +62,7 @@ theorem indicator_apply [DecidableEq ι] : indicator s f i = if hi : i ∈ s the
 
 theorem indicator_injective : Injective fun f : ∀ i ∈ s, α => indicator s f := by
   intro a b h
-  ext (i hi)
+  ext i hi
   rw [← indicator_of_mem hi a, ← indicator_of_mem hi b]
   exact FunLike.congr_fun h i
 #align finsupp.indicator_injective Finsupp.indicator_injective

842328d9

feat: add some lemmas about Finsupp.indicator (#2258)

mathlib3 PR: https://github.com/leanprover-community/mathlib/pull/17413

Co-authored-by: Eric Wieser <wieser.eric@gmail.com>

aa0f33a5

Diff

@@ -4,7 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Yaël Dillies
 
 ! This file was ported from Lean 3 source module data.finsupp.indicator
-! leanprover-community/mathlib commit f7fc89d5d5ff1db2d1242c7bb0e9062ce47ef47c
+! leanprover-community/mathlib commit 842328d9df7e96fd90fc424e115679c15fb23a71
 ! Please do not edit these lines, except to modify the commit id
 ! if you have ported upstream changes.
 -/
@@ -74,4 +74,10 @@ theorem support_indicator_subset : ((indicator s f).support : Set ι) ⊆ s := b
   exact hi (indicator_of_not_mem h _)
 #align finsupp.support_indicator_subset Finsupp.support_indicator_subset
 
+lemma single_eq_indicator (b : α) : single i b = indicator {i} (fun _ _ => b) := by
+  classical
+  ext j
+  simp [single_apply, indicator_apply, @eq_comm _ j]
+#align finsupp.single_eq_indicator Finsupp.single_eq_indicator
+
 end Finsupp

f7fc89d5

feat: port Data.Finsupp.Indicator (#1916)

8f7e7221

`data.finsupp.indicator` ⟷ `Mathlib.Data.Finsupp.Indicator`

Changes since the initial port

Changes in mathlib3

Changes in mathlib3port

Changes in mathlib4

Dependencies 7 + 240

data.finsupp.indicator ⟷ Mathlib.Data.Finsupp.Indicator

Changes since the initial port

Changes in mathlib3

Changes in mathlib3port

Changes in mathlib4

Dependencies 7 + 240

`data.finsupp.indicator` ⟷ `Mathlib.Data.Finsupp.Indicator`