control.fix | 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-2024-03-17-08

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

22f01ce4

Diff

@@ -88,7 +88,7 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
   have : p (Nat.find h') := Nat.find_spec h'
   generalize hk : Nat.find h' = k
   replace hk : Nat.find h' = k + (@upto.zero p).val := hk
-  rw [hk] at this 
+  rw [hk] at this
   revert hk
   dsimp [Part.fix]; rw [assert_pos h']; revert this
   generalize upto.zero = z; intros
@@ -97,7 +97,7 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
   induction k generalizing z <;> intro
   · rw [fix.approx, WellFounded.fix_eq, fix_aux]
     congr; ext : 1; rw [assert_neg]; rfl
-    rw [Nat.zero_add] at this 
+    rw [Nat.zero_add] at this
     simpa only [Classical.not_not, Subtype.val_eq_coe]
   · rw [fix.approx, WellFounded.fix_eq, fix_aux]
     congr; ext : 1
@@ -107,7 +107,7 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
       rw [hk, Nat.succ_add, ← Nat.add_succ]
       apply Nat.lt_of_succ_le
       apply Nat.le_add_left
-    rw [succ_add_eq_succ_add] at this hk 
+    rw [succ_add_eq_succ_add] at this hk
     rw [assert_pos hh, k_ih (upto.succ z hh) this hk]
 #align part.fix_def Part.fix_def
 -/

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 Simon Hudon. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Simon Hudon
 -/
-import Mathbin.Data.Part
-import Mathbin.Data.Nat.Upto
-import Mathbin.Data.Stream.Defs
+import Data.Part
+import Data.Nat.Upto
+import Data.Stream.Defs
 
 #align_import control.fix from "leanprover-community/mathlib"@"c3291da49cfa65f0d43b094750541c0731edc932"

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 Simon Hudon. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Simon Hudon
-
-! This file was ported from Lean 3 source module control.fix
-! 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.Data.Part
 import Mathbin.Data.Nat.Upto
 import Mathbin.Data.Stream.Defs
 
+#align_import control.fix from "leanprover-community/mathlib"@"c3291da49cfa65f0d43b094750541c0731edc932"
+
 /-!
 # Fixed point

c3291da4

bump to nightly-2023-06-01-16

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

b9c87c70

Diff

@@ -91,7 +91,7 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
   have : p (Nat.find h') := Nat.find_spec h'
   generalize hk : Nat.find h' = k
   replace hk : Nat.find h' = k + (@upto.zero p).val := hk
-  rw [hk] at this
+  rw [hk] at this 
   revert hk
   dsimp [Part.fix]; rw [assert_pos h']; revert this
   generalize upto.zero = z; intros
@@ -99,18 +99,18 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
   exact this _
   induction k generalizing z <;> intro
   · rw [fix.approx, WellFounded.fix_eq, fix_aux]
-    congr ; ext : 1; rw [assert_neg]; rfl
-    rw [Nat.zero_add] at this
+    congr; ext : 1; rw [assert_neg]; rfl
+    rw [Nat.zero_add] at this 
     simpa only [Classical.not_not, Subtype.val_eq_coe]
   · rw [fix.approx, WellFounded.fix_eq, fix_aux]
-    congr ; ext : 1
+    congr; ext : 1
     have hh : ¬(fix.approx f z.val x).Dom :=
       by
       apply Nat.find_min h'
       rw [hk, Nat.succ_add, ← Nat.add_succ]
       apply Nat.lt_of_succ_le
       apply Nat.le_add_left
-    rw [succ_add_eq_succ_add] at this hk
+    rw [succ_add_eq_succ_add] at this hk 
     rw [assert_pos hh, k_ih (upto.succ z hh) this hk]
 #align part.fix_def Part.fix_def
 -/

c3291da4

bump to nightly-2023-05-28-18

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

8d353152

Diff

@@ -31,7 +31,7 @@ An instance is defined for `part`.
 
 universe u v
 
-open Classical
+open scoped Classical
 
 variable {α : Type _} {β : α → Type _}

c3291da4

bump to nightly-2023-05-28-04

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

6797a637

Diff

@@ -99,15 +99,11 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
   exact this _
   induction k generalizing z <;> intro
   · rw [fix.approx, WellFounded.fix_eq, fix_aux]
-    congr
-    ext : 1
-    rw [assert_neg]
-    rfl
+    congr ; ext : 1; rw [assert_neg]; rfl
     rw [Nat.zero_add] at this
     simpa only [Classical.not_not, Subtype.val_eq_coe]
   · rw [fix.approx, WellFounded.fix_eq, fix_aux]
-    congr
-    ext : 1
+    congr ; ext : 1
     have hh : ¬(fix.approx f z.val x).Dom :=
       by
       apply Nat.find_min h'

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: adapt to multiple goal linter 1 (#12338)

A PR accompanying #12339.

Zulip discussion

45f93f3f

Diff

@@ -91,9 +91,9 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
     congr
     ext x: 1
     rw [assert_neg]
-    rfl
-    rw [Nat.zero_add] at _this
-    simpa only [not_not, Coe]
+    · rfl
+    · rw [Nat.zero_add] at _this
+      simpa only [not_not, Coe]
   | succ n n_ih =>
     intro x'
     rw [Fix.approx, WellFounded.fix_eq, fixAux]

207cfac9

style: replace '.-/' by '. -/' (#11938)

Purely automatic replacement. If this is in any way controversial; I'm happy to just close this PR.

3556ded2

Diff

@@ -33,7 +33,7 @@ variable {α : Type*} {β : α → Type*}
 /-- `Fix α` provides a `fix` operator to define recursive computation
 via the fixed point of function of type `α → α`. -/
 class Fix (α : Type*) where
-  /-- `fix f` represents the computation of a fixed point for `f`.-/
+  /-- `fix f` represents the computation of a fixed point for `f`. -/
   fix : (α → α) → α
 #align has_fix Fix

207cfac9

chore: scope open Classical (#11199)

We remove all but one open Classicals, instead preferring to use open scoped Classical. The only real side-effect this led to is moving a couple declarations to use Exists.choose instead of Classical.choose.

The first few commits are explicitly labelled regex replaces for ease of review.

c747be0a

Diff

@@ -26,7 +26,7 @@ An instance is defined for `Part`.
 
 universe u v
 
-open Classical
+open scoped Classical
 
 variable {α : Type*} {β : α → Type*}

207cfac9

fix: patch for std4#197 (More add lemmas for Nat) (#6202)

d76f1524

Diff

@@ -101,10 +101,10 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
     ext : 1
     have hh : ¬(Fix.approx f z.val x).Dom := by
       apply Nat.find_min h'
-      rw [hk, Nat.succ_add, ← Nat.add_succ]
+      rw [hk, Nat.succ_add_eq_add_succ]
       apply Nat.lt_of_succ_le
       apply Nat.le_add_left
-    rw [succ_add_eq_succ_add] at _this hk
+    rw [succ_add_eq_add_succ] at _this hk
     rw [assert_pos hh, n_ih (Upto.succ z hh) _this hk]
 #align part.fix_def Part.fix_def

207cfac9

chore: avoid lean3 style have/suffices (#6964)

Many proofs use the "stream of consciousness" style from Lean 3, rather than have ... := or suffices ... from/by.

This PR updates a fraction of these to the preferred Lean 4 style.

I think a good goal would be to delete the "deferred" versions of have, suffices, and let at the bottom of Mathlib.Tactic.Have

(Anyone who would like to contribute more cleanup is welcome to push directly to this branch.)

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

bdc47f68

Diff

@@ -81,9 +81,9 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
   revert hk
   dsimp [Part.fix]; rw [assert_pos h']; revert this
   generalize Upto.zero = z; intro _this hk
-  suffices : ∀ x',
+  suffices ∀ x',
     WellFounded.fix (Part.fix.proof_1 f x h') (fixAux f) z x' = Fix.approx f (succ k) x'
-  exact this _
+    from this _
   induction k generalizing z with
   | zero =>
     intro x'

207cfac9

chore: delay import of Tactic.Common (#7000)

I know that this is contrary to what we've done previously, but:

I'm trying to upstream a great many tactics from Mathlib to Std (essentially, everything that non-mathematicians want too).
This makes it much easier for me to see what is going on, and understand the import requirements (particularly for the "big" tactics norm_num / ring / linarith)
It's actually not as bad as it looks here, because as these tactics move up to Std they will start disappearing again from explicit imports, but Mathlib can happily import all of Std.

(Oh

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

4f3418a7

Diff

@@ -6,6 +6,7 @@ Authors: Simon Hudon
 import Mathlib.Data.Part
 import Mathlib.Data.Nat.Upto
 import Mathlib.Data.Stream.Defs
+import Mathlib.Tactic.Common
 
 #align_import control.fix from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432"

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

@@ -27,11 +27,11 @@ universe u v
 
 open Classical
 
-variable {α : Type _} {β : α → Type _}
+variable {α : Type*} {β : α → Type*}
 
 /-- `Fix α` provides a `fix` operator to define recursive computation
 via the fixed point of function of type `α → α`. -/
-class Fix (α : Type _) where
+class Fix (α : Type*) where
   /-- `fix f` represents the computation of a fixed point for `f`.-/
   fix : (α → α) → α
 #align has_fix Fix

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 Simon Hudon. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Simon Hudon
-
-! This file was ported from Lean 3 source module control.fix
-! 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.Data.Part
 import Mathlib.Data.Nat.Upto
 import Mathlib.Data.Stream.Defs
 
+#align_import control.fix from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432"
+
 /-!
 # Fixed point

207cfac9

chore: fix many typos (#4967)

These are all doc fixes

6f9e51c3

Diff

@@ -32,7 +32,7 @@ open Classical
 
 variable {α : Type _} {β : α → Type _}
 
-/-- `Fix α` provides a `fix` operator to define recursive computatiation
+/-- `Fix α` provides a `fix` operator to define recursive computation
 via the fixed point of function of type `α → α`. -/
 class Fix (α : Type _) where
   /-- `fix f` represents the computation of a fixed point for `f`.-/

207cfac9

feat: make Acc.rec and many related defs computable (#3535)

Lean 4 code generator has had no native supports for Acc.rec. This PR makes Acc.rec computable. This change makes many defs computable. Especially, computable PFun.fix and Part.hasFix enables us to reason about partial functions. This PR also renames some instances and gives PFun.lift @[coe] attr.

31dba13a

Diff

@@ -68,8 +68,7 @@ it satisfies the equations:
   1. `fix f = f (fix f)`          (is a fixed point)
   2. `∀ X, f X ≤ X → fix f ≤ X`   (least fixed point)
 -/
--- porting note: added noncomputable, because WellFounded.fix is noncomputable (for now?)
-protected noncomputable def fix (x : α) : Part (β x) :=
+protected def fix (x : α) : Part (β x) :=
   (Part.assert (∃ i, (Fix.approx f i x).Dom)) fun h =>
     WellFounded.fix.{1} (Nat.Upto.wf h) (fixAux f) Nat.Upto.zero x
 #align part.fix Part.fix
@@ -122,9 +121,9 @@ end Part
 
 namespace Part
 
--- porting note: added noncomputable, because WellFounded.fix is noncomputable (for now?)
-noncomputable instance : Fix (Part α) :=
+instance hasFix : Fix (Part α) :=
   ⟨fun f => Part.fix (fun x u => f (x u)) ()⟩
+#align part.has_fix Part.hasFix
 
 end Part
 
@@ -132,8 +131,7 @@ open Sigma
 
 namespace Pi
 
--- porting note: added noncomputable, because WellFounded.fix is noncomputable (for now?)
-noncomputable instance Part.hasFix {β} : Fix (α → Part β) :=
+instance Part.hasFix {β} : Fix (α → Part β) :=
   ⟨Part.fix⟩
 #align pi.part.has_fix Pi.Part.hasFix

207cfac9

Chore: drop _root_.not_not, export it from Classical (#1954)

This way we don't get a name clash when we open Classical.

Co-authored-by: Johan Commelin <johan@commelin.net>

d3b170e4

Diff

@@ -96,7 +96,7 @@ protected theorem fix_def {x : α} (h' : ∃ i, (Fix.approx f i x).Dom) :
     rw [assert_neg]
     rfl
     rw [Nat.zero_add] at _this
-    simpa only [_root_.not_not, Coe]
+    simpa only [not_not, Coe]
   | succ n n_ih =>
     intro x'
     rw [Fix.approx, WellFounded.fix_eq, fixAux]

207cfac9

chore: tidy various files (#1311)

489ab6d0

Diff

@@ -17,7 +17,7 @@ import Mathlib.Data.Stream.Defs
 
 This module defines a generic `fix` operator for defining recursive
 computations that are not necessarily well-founded or productive.
-An instance is defined for `part`.
+An instance is defined for `Part`.
 
 ## Main definition

207cfac9

feat: port Control.Fix (#1194)

Mathlib Commit : 207cfac9

Co-authored-by: Arien Malec <arien.malec@gmail.com> Co-authored-by: Reid Barton <rwbarton@gmail.com>

89d55079

`control.fix` ⟷ `Mathlib.Control.Fix`

Changes since the initial port

Changes in mathlib3

Changes in mathlib3port

Changes in mathlib4

Dependencies 1 + 80

control.fix ⟷ Mathlib.Control.Fix

Changes since the initial port

Changes in mathlib3

Changes in mathlib3port

Changes in mathlib4

Dependencies 1 + 80

`control.fix` ⟷ `Mathlib.Control.Fix`