ENH: use Zero when zero-initializing types

- makes the intent clearer and avoids the need for additional
  constructor casting. Eg,

      labelList(10, Zero)    vs.  labelList(10, 0)
      scalarField(10, Zero)  vs.  scalarField(10, scalar(0))
      vectorField(10, Zero)  vs.  vectorField(10, vector::zero)

applications/utilities/mesh/advanced/snappyRefineMesh/snappyRefineMesh.C

@@ -752,7 +752,7 @@ int main(int argc, char *argv[])
             IOobject::READ_IF_PRESENT,
             IOobject::AUTO_WRITE
         ),
-        labelList(mesh.nCells(), 0)
+        labelList(mesh.nCells(), Zero)
     );
 
     label maxLevel = max(refLevel);

applications/utilities/mesh/conversion/ansysToFoam/ansysToFoam.L

@@ -542,7 +542,7 @@ int main(int argc, char *argv[])
     // Now split the boundary faces into external and internal faces. All
     // faces go into faceZones and external faces go into patches.
     List<faceList> patchFaces(slPatchCells.size());
-    labelList patchNFaces(slPatchCells.size(), 0);
+    labelList patchNFaces(slPatchCells.size(), Zero);
     forAll(boundary, patchi)
     {
         const faceList& bFaces = boundary[patchi];

applications/utilities/mesh/conversion/fluentMeshToFoam/fluentMeshToFoam.L

@@ -936,7 +936,7 @@ int main(int argc, char *argv[])
 
     labelListList cellFaces(nCells);
 
-    labelList nFacesInCell(nCells, 0);
+    labelList nFacesInCell(nCells, Zero);
 
     forAll(cellFaces, celli)
     {

applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C

@@ -911,7 +911,7 @@ int main(int argc, char *argv[])
 
         List<pointEdgeCollapse> allPointInfo;
         const globalIndex globalPoints(mesh.nPoints());
-        labelList pointPriority(mesh.nPoints(), 0);
+        labelList pointPriority(mesh.nPoints(), Zero);
 
         collapser.consistentCollapse
         (

applications/utilities/mesh/generation/extrude/extrudeMesh/extrudedMesh/extrudedMeshTemplates.C

@@ -219,7 +219,7 @@ Foam::cellList Foam::extrudedMesh::extrudedCells
     }
 
     // Current face count per cell.
-    labelList nCellFaces(eCells.size(), 0);
+    labelList nCellFaces(eCells.size(), Zero);
 
 
     label facei = 0;

applications/utilities/mesh/generation/extrude/extrudeToRegionMesh/extrudeToRegionMesh.C

@@ -2053,11 +2053,11 @@ int main(int argc, char *argv[])
     // Count how many patches on special edges of extrudePatch are necessary
     // - zoneXXX_sides
     // - zoneXXX_zoneYYY
-    labelList zoneSidePatch(zoneNames.size(), 0);
+    labelList zoneSidePatch(zoneNames.size(), Zero);
     // Patch to use for minZone
-    labelList zoneZonePatch_min(zoneNames.size()*zoneNames.size(), 0);
+    labelList zoneZonePatch_min(zoneNames.size()*zoneNames.size(), Zero);
     // Patch to use for maxZone
-    labelList zoneZonePatch_max(zoneNames.size()*zoneNames.size(), 0);
+    labelList zoneZonePatch_max(zoneNames.size()*zoneNames.size(), Zero);
 
     countExtrudePatches
     (

applications/utilities/mesh/generation/extrude2DMesh/extrude2DMeshApp.C

@@ -285,7 +285,7 @@ int main(int argc, char *argv[])
 
         List<pointEdgeCollapse> allPointInfo;
         const globalIndex globalPoints(mesh().nPoints());
-        labelList pointPriority(mesh().nPoints(), 0);
+        labelList pointPriority(mesh().nPoints(), Zero);
 
         collapser.consistentCollapse
         (

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/DelaunayMesh/DistributedDelaunayMesh.C

@@ -44,7 +44,7 @@ Foam::DistributedDelaunayMesh<Triangulation>::buildMap
     // ~~~~~~~~~~~~~~~~~~
 
     // 1. Count
-    labelList nSend(Pstream::nProcs(), 0);
+    labelList nSend(Pstream::nProcs(), Zero);
 
     forAll(toProc, i)
     {

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/PrintTable/PrintTable.C

@@ -77,7 +77,7 @@ void Foam::PrintTable<KeyType, DataType>::print
         label largestKeyLength = 6;
         label largestDataLength = 0;
 
-        List<label> largestProcSize(Pstream::nProcs(), 0);
+        labelList largestProcSize(Pstream::nProcs(), Zero);
 
         forAll(procData, proci)
         {

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/backgroundMeshDecomposition/backgroundMeshDecomposition.C

@@ -51,7 +51,7 @@ Foam::autoPtr<Foam::mapDistribute> Foam::backgroundMeshDecomposition::buildMap
     // ~~~~~~~~~~~~~~~~~~
 
     // 1. Count
-    labelList nSend(Pstream::nProcs(), 0);
+    labelList nSend(Pstream::nProcs(), Zero);
 
     forAll(toProc, i)
     {
@@ -337,7 +337,7 @@ void Foam::backgroundMeshDecomposition::initialRefinement()
                 (
                     cellsToRemove,
                     exposedFaces,
-                    labelList(exposedFaces.size(), 0),  // patchID dummy
+                    labelList(exposedFaces.size(), Zero),  // patchID dummy
                     meshMod
                 );
 
@@ -793,8 +793,8 @@ Foam::backgroundMeshDecomposition::backgroundMeshDecomposition
     meshCutter_
     (
         mesh_,
-        labelList(mesh_.nCells(), 0),
-        labelList(mesh_.nPoints(), 0)
+        labelList(mesh_.nCells(), Zero),
+        labelList(mesh_.nPoints(), Zero)
     ),
     boundaryFacesPtr_(),
     bFTreePtr_(),

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/conformalVoronoiMesh/conformalVoronoiMeshCalcDualMesh.C

@@ -1063,7 +1063,7 @@ Foam::labelHashSet Foam::conformalVoronoiMesh::checkPolyMeshQuality
 
         // Check for cells with one internal face only
 
-        labelList nInternalFaces(pMesh.nCells(), label(0));
+        labelList nInternalFaces(pMesh.nCells(), Zero);
 
         for (label fI = 0; fI < pMesh.nInternalFaces(); fI++)
         {

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/conformalVoronoiMesh/conformalVoronoiMeshFeaturePoints.C

@@ -902,7 +902,7 @@ void Foam::conformalVoronoiMesh::createMultipleEdgePointGroup
     const List<extendedFeatureEdgeMesh::sideVolumeType>& normalVolumeTypes =
         feMesh.normalVolumeTypes();
 
-    labelList nNormalTypes(4, label(0));
+    labelList nNormalTypes(4, Zero);
 
     forAll(edNormalIs, edgeNormalI)
     {

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/conformalVoronoiMesh/conformalVoronoiMeshIO.C

@@ -210,7 +210,7 @@ void Foam::conformalVoronoiMesh::writeMesh(const fileName& instance)
 //
 //        // From all Delaunay vertices to cell (positive index)
 //        // or patch face (negative index)
-//        labelList vertexToDualAddressing(number_of_vertices(), 0);
+//        labelList vertexToDualAddressing(number_of_vertices(), Zero);
 //
 //        forAll(cellToDelaunayVertex, celli)
 //        {
@@ -525,7 +525,7 @@ void Foam::conformalVoronoiMesh::reorderPoints
     Info<< incrIndent << indent << "Reordering points into internal/external"
         << endl;
 
-    labelList oldToNew(points.size(), label(0));
+    labelList oldToNew(points.size(), Zero);
 
     // Find points that are internal
     for (label fI = nInternalFaces; fI < faces.size(); ++fI)
@@ -611,7 +611,7 @@ void Foam::conformalVoronoiMesh::reorderProcessorPatches
     const fvMesh& sortMesh = sortMeshPtr();
 
     // Rotation on new faces.
-    labelList rotation(faces.size(), label(0));
+    labelList rotation(faces.size(), Zero);
     labelList faceMap(faces.size(), label(-1));
 
     PstreamBuffers pBufs(Pstream::commsTypes::nonBlocking);
@@ -660,7 +660,7 @@ void Foam::conformalVoronoiMesh::reorderProcessorPatches
                 patchDicts[patchi].get<label>("startFace");
 
             labelList patchFaceMap(nPatchFaces, label(-1));
-            labelList patchFaceRotation(nPatchFaces, label(0));
+            labelList patchFaceRotation(nPatchFaces, Zero);
 
             bool changed = refCast<const processorPolyPatch>(pp).order
             (

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/conformalVoronoiMesh/conformalVoronoiMeshTemplates.C

@@ -83,7 +83,7 @@ bool Foam::conformalVoronoiMesh::distributeBackground(const Triangulation& mesh)
 
         meshSearch cellSearch(bMesh, polyMesh::FACE_PLANES);
 
-        labelList cellVertices(bMesh.nCells(), label(0));
+        labelList cellVertices(bMesh.nCells(), Zero);
 
         for
         (

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/conformationSurfaces/conformationSurfaces.C

@@ -613,7 +613,7 @@ Foam::Field<bool> Foam::conformationSurfaces::inside
     const pointField& samplePts
 ) const
 {
-    return wellInside(samplePts, scalarField(samplePts.size(), 0.0));
+    return wellInside(samplePts, scalarField(samplePts.size(), Zero));
 }
 
 
@@ -622,7 +622,7 @@ bool Foam::conformationSurfaces::inside
     const point& samplePt
 ) const
 {
-    return wellInside(pointField(1, samplePt), scalarField(1, 0))[0];
+    return wellInside(pointField(1, samplePt), scalarField(1, Zero))[0];
 }
 
 
@@ -631,7 +631,7 @@ Foam::Field<bool> Foam::conformationSurfaces::outside
     const pointField& samplePts
 ) const
 {
-    return wellOutside(samplePts, scalarField(samplePts.size(), 0.0));
+    return wellOutside(samplePts, scalarField(samplePts.size(), Zero));
 }
 
 
@@ -640,7 +640,7 @@ bool Foam::conformationSurfaces::outside
     const point& samplePt
 ) const
 {
-    return wellOutside(pointField(1, samplePt), scalarField(1, 0))[0];
+    return wellOutside(pointField(1, samplePt), scalarField(1, Zero))[0];
     //return !inside(samplePt);
 }
 

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/initialPointsMethod/autoDensity/autoDensity.C

@@ -416,7 +416,7 @@ bool Foam::autoDensity::fillBox
 
             pointField linePoints(nLine, Zero);
 
-            scalarField lineSizes(nLine, 0.0);
+            scalarField lineSizes(nLine, Zero);
 
             for (label i = 0; i < surfRes_; i++)
             {

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/searchableSurfaceFeatures/searchableBoxFeatures.C

@@ -113,7 +113,7 @@ Foam::searchableBoxFeatures::features() const
             surfacePoints[treeBoundBox::edges[eI].end()]
           - surfacePoints[treeBoundBox::edges[eI].start()];
 
-        normalDirections[eI] = labelList(2, label(0));
+        normalDirections[eI] = labelList(2, Zero);
         for (label j = 0; j < 2; ++j)
         {
             const vector cross =

applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/searchableSurfaceFeatures/searchablePlateFeatures.C

@@ -131,7 +131,7 @@ Foam::searchablePlateFeatures::features() const
             surface().points()()[edges[eI].end()]
           - surface().points()()[edges[eI].start()];
 
-        normalDirections[eI] = labelList(2, label(0));
+        normalDirections[eI] = labelList(2, Zero);
         for (label j = 0; j < 2; ++j)
         {
             const vector cross =

applications/utilities/mesh/generation/snappyHexMesh/snappyHexMesh.C

@@ -108,9 +108,9 @@ autoPtr<refinementSurfaces> createRefinementSurfaces
 
     labelList regionOffset(surfi);
 
-    labelList globalMinLevel(surfi, 0);
-    labelList globalMaxLevel(surfi, 0);
-    labelList globalLevelIncr(surfi, 0);
+    labelList globalMinLevel(surfi, Zero);
+    labelList globalMaxLevel(surfi, Zero);
+    labelList globalLevelIncr(surfi, Zero);
     PtrList<dictionary> globalPatchInfo(surfi);
     List<Map<label>> regionMinLevel(surfi);
     List<Map<label>> regionMaxLevel(surfi);
@@ -263,8 +263,8 @@ autoPtr<refinementSurfaces> createRefinementSurfaces
     }
 
     // Rework surface specific information into information per global region
-    labelList minLevel(nRegions, 0);
-    labelList maxLevel(nRegions, 0);
+    labelList minLevel(nRegions, Zero);
+    labelList maxLevel(nRegions, Zero);
     labelList gapLevel(nRegions, -1);
     PtrList<dictionary> patchInfo(nRegions);
 

applications/utilities/mesh/manipulation/checkMesh/checkTopology.C

@@ -319,7 +319,7 @@ Foam::label Foam::checkTopology
 
     if (allTopology)
     {
-        labelList nInternalFaces(mesh.nCells(), 0);
+        labelList nInternalFaces(mesh.nCells(), Zero);
 
         for (label facei = 0; facei < mesh.nInternalFaces(); facei++)
         {