ENH: promote ListOps::identity to Foam::identity

- becoming more frequently used and there is no ambiguity in calling
  parameters either - identity(label) vs identity(labelUList&).

  Provide both int32 and int64 versions.

applications/test/DynamicList2/Test-DynamicList2.C

@@ -133,7 +133,7 @@ int main(int argc, char *argv[])
         DynamicList<label, 64> list1;
 
         list1.resize(4);
-        ListOps::identity(list1);
+        Foam::identity(list1);
 
         list1.resize(3);
         printInfo("", list1);
@@ -152,7 +152,7 @@ int main(int argc, char *argv[])
         DynamicList<label, 64> list2;
 
         list2.resize(5);
-        ListOps::identity(list2);
+        Foam::identity(list2);
 
         Info<< "initial list" << nl;
         printInfo("", list2);

applications/test/List/Test-List.C

@@ -147,7 +147,7 @@ int main(int argc, char *argv[])
 
     {
         List<label> ident(15);
-        std::iota(ident.begin(), ident.end(), 0);
+        Foam::identity(ident, 0);
 
         Info<<"Ident:";
         forAllConstIters(ident, iter)
@@ -546,10 +546,10 @@ int main(int argc, char *argv[])
             Info<< "scalars: " << flatOutput(scalars) << endl;
         }
 
-        #if WM_LABEL_SIZE == 32
+        // #if WM_LABEL_SIZE == 32
         {
             List<int64_t> input(10);
-            std::iota(input.begin(), input.end(), 50);
+            Foam::identity(input, 50);
 
             auto output = ListOps::create<label>
             (
@@ -558,10 +558,10 @@ int main(int argc, char *argv[])
             );
             Info<< "label (from int64): " << flatOutput(output) << endl;
         }
-        #elif WM_LABEL_SIZE == 64
+        // #elif WM_LABEL_SIZE == 64
         {
             List<int32_t> input(10);
-            std::iota(input.begin(), input.end(), 50);
+            Foam::identity(input, 50);
 
             auto output = ListOps::create<label>
             (
@@ -570,7 +570,7 @@ int main(int argc, char *argv[])
             );
             Info<< "label (from int32): " << flatOutput(output) << endl;
         }
-        #endif
+        // #endif
 
 
         labelHashSet locations{ -15, 5, 10, 15, 25, 35 };

applications/test/SubField/Test-SubField.C

@@ -59,7 +59,7 @@ int main(int argc, char *argv[])
 
     {
         List<label> ident(25);
-        std::iota(ident.begin(), ident.end(), 0);
+        Foam::identity(ident, 0);
 
         print(ident);
 
@@ -108,7 +108,7 @@ int main(int argc, char *argv[])
 
         // This is also possible since we hold a concrete pointer/size
         // and not an intermediate
-        ListOps::identity(sub.reset(ident, 8, 8));
+        Foam::identity(sub.reset(ident, 8, 8));
         print(sub);
         print(ident);
     }

applications/utilities/mesh/manipulation/stitchMesh/stitchMesh.C

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2017-2022 OpenCFD Ltd.
+    Copyright (C) 2017-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -523,8 +523,8 @@ int main(int argc, char *argv[])
         labelList faceIds;
 
         // Markup master face ids
-        faceIds.setSize(masterPatch.size());
-        std::iota(faceIds.begin(), faceIds.end(), masterPatch.start());
+        faceIds.resize_nocopy(masterPatch.size());
+        Foam::identity(faceIds, masterPatch.start());
 
         stitcher.clear();
         stitcher.setSize(1);
@@ -569,8 +569,8 @@ int main(int argc, char *argv[])
             ).resetAddressing(std::move(faceIds), false);
 
             // Markup slave face ids
-            faceIds.setSize(slavePatch.size());
-            std::iota(faceIds.begin(), faceIds.end(), slavePatch.start());
+            faceIds.resize_nocopy(slavePatch.size());
+            Foam::identity(faceIds, slavePatch.start());
 
             mesh.faceZones()
             (

src/OpenFOAM/Make/files

@@ -62,7 +62,7 @@ $(ints)/int32/int32IO.C
 $(ints)/int64/int64.C
 $(ints)/int64/int64IO.C
 $(ints)/label/label.C
-$(ints)/lists/labelList.C
+$(ints)/lists/labelLists.C
 $(ints)/lists/labelIOList.C
 $(ints)/lists/labelListIOList.C
 

src/OpenFOAM/containers/IndirectLists/SortList/SortListI.H

@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2019-2022 OpenCFD Ltd.
+    Copyright (C) 2019-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -25,8 +25,6 @@ License
 
 \*---------------------------------------------------------------------------*/
 
-#include "ListOps.H"  // For identity
-
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 template<class T>
@@ -77,7 +75,7 @@ inline void Foam::SortList<T>::reset()
     auto& addr = this->indices();
 
     addr.resize_nocopy(this->values().size());
-    ListOps::identity(addr);
+    Foam::identity(addr, 0);
 }
 
 
@@ -89,7 +87,7 @@ inline void Foam::SortList<T>::sort(const Compare& comp)
     auto& addr = this->indices();
 
     addr.resize_nocopy(vals.size());
-    ListOps::identity(addr);
+    Foam::identity(addr, 0);
 
     std::stable_sort
     (

src/OpenFOAM/containers/Lists/List/List.C

@@ -481,14 +481,7 @@ void Foam::sortedOrder
     // List lengths must be identical. Old content is overwritten
     order.resize_nocopy(list.size());
 
-    // Same as std::iota and ListOps::identity
-    label value = 0;
-    for (label& item : order)
-    {
-        item = value;
-        ++value;
-    }
-
+    Foam::identity(order, 0);
     Foam::stableSort(order, comp);
 }
 

src/OpenFOAM/containers/Lists/List/List.H

@@ -431,7 +431,8 @@ Istream& operator>>(Istream& is, List<T>& list)
 
 // * * * * * * * * * * * * * * Global Functions  * * * * * * * * * * * * * * //
 
-//- Return an identity map of the given length with (map[i] == i)
+//- Return an identity map of the given length with (map[i] == i),
+//- works like std::iota() but returning a list of label values.
 //  Optionally with an alternative start index, so that (map[i] == i+start)
 labelList identity(const label len, label start=0);
 

src/OpenFOAM/containers/Lists/List/UList.H

@@ -201,7 +201,7 @@ public:
 
             bool operator()(const label a, const label b) const
             {
-                return values[a] < values[b];
+                return (values[a] < values[b]);
             }
         };
 
@@ -217,7 +217,7 @@ public:
 
             bool operator()(const label a, const label b) const
             {
-                return values[b] < values[a];
+                return (values[b] < values[a]);
             }
         };
 
@@ -677,6 +677,14 @@ Ostream& operator<<(Ostream& os, const std::vector<T>& list);
 
 // * * * * * * * * * * * * * * Global Functions  * * * * * * * * * * * * * * //
 
+//- Fill an identity map with (map[i] == i), works like std::iota().
+//  Optionally with an alternative start index, so that (map[i] == i+start)
+void identity(UList<int32_t>& map, int32_t start = 0);
+
+//- Fill an identity map with (map[i] == i), works like std::iota().
+//  Optionally with an alternative start index, so that (map[i] == i+start)
+void identity(UList<int64_t>& map, int64_t start = 0);
+
 //- Sort the list
 template<class T>
 void sort(UList<T>& list);

src/OpenFOAM/containers/Lists/ListOps/ListOps.C

@@ -200,12 +200,6 @@ void Foam::inplaceReorder
 }
 
 
-void Foam::ListOps::identity(labelUList& map, label start)
-{
-    std::iota(map.begin(), map.end(), start);
-}
-
-
 void Foam::ListOps::unionEqOp::operator()
 (
     labelList& x,

src/OpenFOAM/containers/Lists/ListOps/ListOps.H

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2017-2022 OpenCFD Ltd.
+    Copyright (C) 2017-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -593,7 +593,7 @@ struct less
 
     bool operator()(const label a, const label b) const
     {
-        return values[a] < values[b];
+        return (values[a] < values[b]);
     }
 };
 
@@ -611,14 +611,19 @@ struct greater
 
     bool operator()(const label a, const label b) const
     {
-        return values[b] < values[a];
+        return (values[b] < values[a]);
     }
 };
 
 
-//- Set identity map with (map[i] == i)
+//- Fill an identity map with (map[i] == i)
 //  Optionally with an alternative start index, so that (map[i] == i+start)
-void identity(labelUList& map, label start=0);
+FOAM_DEPRECATED_STRICT(2023-10, "Foam::identity(...)")
+inline void identity(labelUList& map, label start = 0)
+{
+    Foam::identity(map, start);
+}
+
 
 //- Count the number of matching entries.
 //  When start is specified, any occurrences before start are ignored.

src/OpenFOAM/containers/Lists/SortableList/SortableList.C

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2017-2022 OpenCFD Ltd.
+    Copyright (C) 2017-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -26,8 +26,6 @@ License
 
 \*---------------------------------------------------------------------------*/
 
-#include "ListOps.H"  // For identity
-
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 template<class T>
@@ -136,7 +134,7 @@ template<class T>
 void Foam::SortableList<T>::partialSort(label n, label start)
 {
     indices_.resize_nocopy(this->size());
-    ListOps::identity(indices_);
+    Foam::identity(indices_, 0);
 
     // Forward partial sort of indices
     std::partial_sort
@@ -156,7 +154,7 @@ template<class T>
 void Foam::SortableList<T>::partialReverseSort(label n, label start)
 {
     indices_.resize_nocopy(this->size());
-    ListOps::identity(indices_);
+    Foam::identity(indices_, 0);
 
     // Reverse partial sort of indices
     std::partial_sort

src/OpenFOAM/containers/PtrLists/PtrListOps/PtrListOpsTemplates.C

@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2019-2022 OpenCFD Ltd.
+    Copyright (C) 2019-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -63,13 +63,7 @@ void Foam::sortedOrder
     // List lengths must be identical. Old content is overwritten
     order.resize_nocopy(list.size());
 
-    // Same as std::iota and ListOps::identity
-    label value = 0;
-    for (label& item : order)
-    {
-        item = value;
-        ++value;
-    }
+    Foam::identity(order, 0);
 
     std::stable_sort(order.begin(), order.end(), comp);
 }

src/OpenFOAM/matrices/SquareMatrix/SquareMatrix.C

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2013-2016 OpenFOAM Foundation
-    Copyright (C) 2019-2020 OpenCFD Ltd.
+    Copyright (C) 2019-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -28,19 +28,17 @@ License
 
 #include "SquareMatrix.H"
 #include "RectangularMatrix.H"
-#include "labelList.H"
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 template<class Type>
 template<class CompOp>
-Foam::List<Foam::label> Foam::SquareMatrix<Type>::sortPermutation
+Foam::labelList Foam::SquareMatrix<Type>::sortPermutation
 (
     CompOp& compare
 ) const
 {
-    List<label> p(this->m());
-    std::iota(p.begin(), p.end(), 0);
+    labelList p = Foam::identity(this->m());
     std::sort
     (
         p.begin(),
@@ -53,7 +51,7 @@ Foam::List<Foam::label> Foam::SquareMatrix<Type>::sortPermutation
 
 
 template<class Type>
-void Foam::SquareMatrix<Type>::applyPermutation(const List<label>& p)
+void Foam::SquareMatrix<Type>::applyPermutation(const labelUList& p)
 {
     #ifdef FULLDEBUG
     if (this->m() != p.size())

src/OpenFOAM/matrices/SquareMatrix/SquareMatrix.H

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2019-2022 OpenCFD Ltd.
+    Copyright (C) 2019-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -40,8 +40,8 @@ SourceFiles
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef SquareMatrix_H
-#define SquareMatrix_H
+#ifndef Foam_SquareMatrix_H
+#define Foam_SquareMatrix_H
 
 #include "Matrix.H"
 #include "Identity.H"
@@ -65,7 +65,6 @@ class SquareMatrix
 :
     public Matrix<SquareMatrix<Type>, Type>
 {
-
 public:
 
     // Generated Methods
@@ -172,14 +171,13 @@ public:
 
     // Sort
 
-        //- Return a sort permutation labelList according to
-        //- a given comparison on the diagonal entries
+        //- Return a sort permutation using the given comparison operator
+        //- on the diagonal entries
         template<class CompOp>
-        List<label> sortPermutation(CompOp& compare) const;
+        labelList sortPermutation(CompOp& compare) const;
 
-        //- Column-reorder this Matrix according to
-        //- a given permutation labelList
-        void applyPermutation(const List<label>& p);
+        //- Column-reorder this Matrix according to the given permutation
+        void applyPermutation(const labelUList& p);
 
 
     // Member Operators

src/OpenFOAM/meshes/meshTools/mergePoints.C

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2017-2022 OpenCFD Ltd.
+    Copyright (C) 2017-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -26,7 +26,7 @@ License
 
 \*---------------------------------------------------------------------------*/
 
-#include "ListOps.H"  // sortedOrder, ListOps::identity
+#include "ListOps.H"  // sortedOrder
 
 // * * * * * * * * * * * * * * * Implementation  * * * * * * * * * * * * * * //
 
@@ -230,7 +230,7 @@ Foam::label Foam::Detail::mergePoints
     // Setup initial identity +1 mapping for pointToUnique
     // The +1 allows negatives to mark duplicates
 
-    ListOps::identity(pointToUnique, 1);
+    Foam::identity(pointToUnique, 1);
 
     // The newPointCounts is an offsets table that we use to walk
     // across the adjacency list (lookupMerged), picking the original

src/OpenFOAM/primitives/ints/lists/labelLists.C

@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2019 OpenCFD Ltd.
+    Copyright (C) 2019-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -30,11 +30,24 @@ License
 
 // * * * * * * * * * * * * * * Global Data Members * * * * * * * * * * * * * //
 
+// This was deprecated (2019-02) in favour of labelList::null()
 const Foam::labelList Foam::emptyLabelList;
 
 
 // * * * * * * * * * * * * * * * Global Functions  * * * * * * * * * * * * * //
 
+void Foam::identity(Foam::UList<int32_t>& map, int32_t start)
+{
+    std::iota(map.begin(), map.end(), start);
+}
+
+
+void Foam::identity(Foam::UList<int64_t>& map, int64_t start)
+{
+    std::iota(map.begin(), map.end(), start);
+}
+
+
 Foam::labelList Foam::identity(const label len, label start)
 {
     labelList map(len);

src/fileFormats/ensight/part/cells/ensightCellsAddr.C

@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2020-2022 OpenCFD Ltd.
+    Copyright (C) 2020-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -161,16 +161,16 @@ Foam::label Foam::ensightCells::meshPointMapppings
         // Non-parallel
 
         nPoints = mesh.nPoints();
-        pointToGlobal.resize(nPoints);
+        pointToGlobal.resize_nocopy(nPoints);
 
         if (allCells)
         {
             // All cells used, and thus all points
 
-            uniqueMeshPointLabels.resize(nPoints);
+            uniqueMeshPointLabels.resize_nocopy(nPoints);
 
-            ListOps::identity(pointToGlobal);
-            ListOps::identity(uniqueMeshPointLabels);
+            Foam::identity(pointToGlobal);
+            Foam::identity(uniqueMeshPointLabels);
         }
         else
         {

src/fileFormats/ensight/part/faces/ensightFacesIO.C

@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2020-2022 OpenCFD Ltd.
+    Copyright (C) 2020-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -88,8 +88,8 @@ void Foam::ensightFaces::write
         nPoints = pp.meshPoints().size();
         uniqueMeshPointLabels = pp.meshPoints();
 
-        pointToGlobal.resize(nPoints);
-        ListOps::identity(pointToGlobal);
+        pointToGlobal.resize_nocopy(nPoints);
+        Foam::identity(pointToGlobal);
     }
 
     ensightOutput::Detail::writeCoordinates

src/fileFormats/vtk/part/foamVtuSizingImpl.C

@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2016-2022 OpenCFD Ltd.
+    Copyright (C) 2016-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -858,7 +858,7 @@ void Foam::vtk::vtuSizing::populateArrays
 
     // May have been done by caller,
     // but for additional safety set an identity mapping
-    ListOps::identity(cellMap);
+    Foam::identity(cellMap);
 
     // ===========================================
     // Adjust vertOffset for all cells