modernize C++: use transparent functors

src/App/ElementMap.h

@@ -267,7 +267,7 @@ private:
 
     std::map<const char*, IndexedElements, CStringComp> indexedNames;
 
-    std::map<MappedName, IndexedName, std::less<MappedName>> mappedNames;
+    std::map<MappedName, IndexedName, std::less<>> mappedNames;
 
     struct ChildMapInfo
     {

src/Gui/ShortcutManager.cpp

@@ -344,7 +344,7 @@ std::vector<std::pair<QByteArray, QAction*>> ShortcutManager::getActionsByShortc
 {
     const auto &index = actionMap.get<1>();
     std::vector<std::pair<QByteArray, QAction*>> res;
-    std::multimap<int, const ActionData*, std::greater<int>> map;
+    std::multimap<int, const ActionData*, std::greater<>> map;
     for (auto it = index.lower_bound(ActionKey(shortcut)); it != index.end(); ++it) {
         if (it->key.shortcut != shortcut)
             break;

src/Mod/Mesh/App/Core/Builder.cpp

@@ -337,7 +337,7 @@ void MeshFastBuilder::Finish ()
 
     //std::sort(verts.begin(), verts.end());
     int threads = QThread::idealThreadCount();
-    MeshCore::parallel_sort(verts.begin(), verts.end(), std::less<Private::Vertex>(), threads);
+    MeshCore::parallel_sort(verts.begin(), verts.end(), std::less<>(), threads);
 
     QVector<FacetIndex> indices(ulCtPts);
 

src/Mod/Mesh/App/Core/Degeneration.cpp

@@ -517,7 +517,7 @@ bool MeshRemoveNeedles::Fixup()
 
     std::priority_queue<FaceEdgePriority,
                         std::vector<FaceEdgePriority>,
-                        std::greater<FaceEdgePriority> > todo;
+                        std::greater<> > todo;
     for (std::size_t index = 0; index < facetCount; index++) {
         const MeshFacet& facet = rclFAry[index];
         MeshGeomFacet tria(_rclMesh.GetFacet(facet));
@@ -615,7 +615,7 @@ bool MeshFixCaps::Fixup()
 
     std::priority_queue<FaceVertexPriority,
                         std::vector<FaceVertexPriority>,
-                        std::greater<FaceVertexPriority> > todo;
+                        std::greater<> > todo;
     for (std::size_t index = 0; index < facetCount; index++) {
         for (int i=0; i<3; i++) {
             const MeshFacet& facet = rclFAry[index];

src/Mod/Sketcher/Gui/CommandSketcherTools.cpp

@@ -50,7 +50,8 @@
 #include "Utils.h"
 #include "ViewProviderSketch.h"
 
-
+// Hint: this is to prevent to re-format big parts of the file. Remove it later again.
+// clang-format off
 using namespace std;
 using namespace SketcherGui;
 using namespace Sketcher;
@@ -806,7 +807,7 @@ void CmdSketcherRestoreInternalAlignmentGeometry::activated(int iMsg)
 
     // Handle highest GeoIds first to minimize GeoIds changing
     // TODO: this might not completely resolve GeoIds changing
-    std::sort(SubGeoIds.begin(), SubGeoIds.end(), std::greater<int>());
+    std::sort(SubGeoIds.begin(), SubGeoIds.end(), std::greater<>());
     // Keep unique
     SubGeoIds.erase(std::unique(SubGeoIds.begin(), SubGeoIds.end()), SubGeoIds.end());
 
@@ -2277,3 +2278,4 @@ void CreateSketcherCommandsConstraintAccel()
     rcCmdMgr.addCommand(new CmdSketcherDeleteAllConstraints());
     rcCmdMgr.addCommand(new CmdSketcherRemoveAxesAlignment());
 }
+// clang-format on

src/Mod/Spreadsheet/Gui/SheetTableView.cpp

@@ -370,7 +370,7 @@ void SheetTableView::removeRows()
     /* Make sure rows are sorted in descending order */
     for (QModelIndexList::const_iterator it = rows.cbegin(); it != rows.cend(); ++it)
         sortedRows.push_back(it->row());
-    std::sort(sortedRows.begin(), sortedRows.end(), std::greater<int>());
+    std::sort(sortedRows.begin(), sortedRows.end(), std::greater<>());
 
     /* Remove rows */
     Gui::Command::openCommand(QT_TRANSLATE_NOOP("Command", "Remove rows"));
@@ -443,7 +443,7 @@ void SheetTableView::removeColumns()
     /* Make sure rows are sorted in descending order */
     for (QModelIndexList::const_iterator it = cols.cbegin(); it != cols.cend(); ++it)
         sortedColumns.push_back(it->column());
-    std::sort(sortedColumns.begin(), sortedColumns.end(), std::greater<int>());
+    std::sort(sortedColumns.begin(), sortedColumns.end(), std::greater<>());
 
     /* Remove columns */
     Gui::Command::openCommand(QT_TRANSLATE_NOOP("Command", "Remove rows"));

src/Mod/TechDraw/App/DrawViewPart.cpp

@@ -748,7 +748,7 @@ std::vector<TechDraw::DrawViewDimension*> DrawViewPart::getDimensions() const
 {
     std::vector<TechDraw::DrawViewDimension*> result;
     std::vector<App::DocumentObject*> children = getInList();
-    std::sort(children.begin(), children.end(), std::less<App::DocumentObject*>());
+    std::sort(children.begin(), children.end(), std::less<>());
     std::vector<App::DocumentObject*>::iterator newEnd =
         std::unique(children.begin(), children.end());
     for (std::vector<App::DocumentObject*>::iterator it = children.begin(); it != newEnd; ++it) {
@@ -764,7 +764,7 @@ std::vector<TechDraw::DrawViewBalloon*> DrawViewPart::getBalloons() const
 {
     std::vector<TechDraw::DrawViewBalloon*> result;
     std::vector<App::DocumentObject*> children = getInList();
-    std::sort(children.begin(), children.end(), std::less<App::DocumentObject*>());
+    std::sort(children.begin(), children.end(), std::less<>());
     std::vector<App::DocumentObject*>::iterator newEnd =
         std::unique(children.begin(), children.end());
     for (std::vector<App::DocumentObject*>::iterator it = children.begin(); it != newEnd; ++it) {