STYLE: Use auto for declaration of variables initialized by New()

Replaced initializations of the form `T::Pointer var = T::New()`
(sometimes starting with `typename`) with `auto var = T::New()`, to
reduce code redundancy.

In accordance with C++ Core Guidelines, August 19, 2021:
"ES.11: Use `auto` to avoid redundant repetition of type names"
https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Res-auto

Using Notepad++ v8.1.4, Find in Files (Regular expression):

    Find what:  typename (\w+)::Pointer[ ]+(\w+) = \1::New\(\);
    Replace with:  auto $2 = $1::New\(\);
    Filters: itk*.hxx;itk*.h;itk*.cxx

And then again without `typename`:

    Find what:  (\w+)::Pointer[ ]+(\w+) = \1::New\(\);

Follow-up to commit de713e7
"STYLE: Use auto for variable creation", Hans Johnson, 9 February 2018.

Examples/IO/XML/itkParticleSwarmOptimizerDOMReader.cxx

@@ -36,7 +36,7 @@ ParticleSwarmOptimizerDOMReader::GenerateData(const DOMNodeType * inputdom,
   if (output == nullptr)
   {
     logger->Info("creating the output PSO object ...\n");
-    OutputType::Pointer object = OutputType::New();
+    auto object = OutputType::New();
     output = (OutputType *)object;
     this->SetOutput(output);
   }

Examples/IO/XML/itkParticleSwarmOptimizerDOMWriter.cxx

@@ -78,21 +78,21 @@ ParticleSwarmOptimizerDOMWriter::GenerateData(DOMNodeType * outputdom,
   }
   // generate and insert the DOM node for the lower bound of the parameters
   logger->Info("writing LowerBound ...\n");
-  DOMNode::Pointer nodelb = DOMNode::New();
+  auto nodelb = DOMNode::New();
   nodelb->SetName("bound");
   nodelb->SetAttribute("id", "lower");
   nodelb->SetAttribute("value", s << ClearContent << lbound);
   outputdom->AddChildAtEnd(nodelb);
   // generate and insert the DOM node for the upper bound of the parameters
   logger->Info("writing UpperBound ...\n");
-  DOMNode::Pointer nodeub = DOMNode::New();
+  auto nodeub = DOMNode::New();
   nodeub->SetName("bound");
   nodeub->SetAttribute("id", "upper");
   nodeub->SetAttribute("value", s << ClearContent << ubound);
   outputdom->AddChildAtEnd(nodeub);
 
   logger->Info("writing ParametersConvergenceTolerance ...\n");
-  DOMNode::Pointer nodeptols = DOMNode::New();
+  auto nodeptols = DOMNode::New();
   nodeptols->SetName("ParametersConvergenceTolerance");
   outputdom->AddChildAtEnd(nodeptols);
   s << ClearContent

Modules/Bridge/NumPy/include/itkPyBuffer.hxx

@@ -158,9 +158,9 @@ PyBuffer<TImage>::_GetImageViewFromArray(PyObject * arr, PyObject * shape, PyObj
 
   using InternalPixelType = typename TImage::InternalPixelType;
   using ImporterType = ImportImageContainer<SizeValueType, InternalPixelType>;
-  typename ImporterType::Pointer importer = ImporterType::New();
-  constexpr bool                 importImageFilterWillOwnTheBuffer = false;
-  InternalPixelType *            data = (InternalPixelType *)buffer;
+  auto                importer = ImporterType::New();
+  constexpr bool      importImageFilterWillOwnTheBuffer = false;
+  InternalPixelType * data = (InternalPixelType *)buffer;
   importer->SetImportPointer(data, numberOfPixels, importImageFilterWillOwnTheBuffer);
 
   OutputImagePointer output = TImage::New();

Modules/Bridge/NumPy/include/itkPyVectorContainer.hxx

@@ -105,8 +105,8 @@ PyVectorContainer<TElementIdentifier, TElement>::_vector_container_from_array(Py
     PyBuffer_Release(&pyBuffer);
     return nullptr;
   }
-  DataType *                            data = (DataType *)buffer;
-  typename VectorContainerType::Pointer output = VectorContainerType::New();
+  DataType * data = (DataType *)buffer;
+  auto       output = VectorContainerType::New();
   output->resize(numberOfElements);
   for (size_t ii = 0; ii < numberOfElements; ++ii)
   {

Modules/Bridge/VtkGlue/test/itkImageToVTKImageFilterRGBTest.cxx

@@ -41,11 +41,11 @@ itkImageToVTKImageFilterRGBTest(int argc, char * argv[])
   using ImageType = itk::Image<PixelType, Dimension>;
 
   using ReaderType = itk::ImageFileReader<ImageType>;
-  ReaderType::Pointer reader = ReaderType::New();
+  auto reader = ReaderType::New();
   reader->SetFileName(inputFileName);
 
   using ConnectorType = itk::ImageToVTKImageFilter<ImageType>;
-  ConnectorType::Pointer connector = ConnectorType::New();
+  auto connector = ConnectorType::New();
   connector->SetInput(reader->GetOutput());
 
   connector->UpdateLargestPossibleRegion();

Modules/Bridge/VtkGlue/test/itkImageToVTKImageFilterTest.cxx

@@ -37,7 +37,7 @@ itkImageToVTKImageFilterTest(int, char *[])
   size[0] = 40;
   size[1] = 10;
   size[2] = 20;
-  SourceType::Pointer source = SourceType::New();
+  auto source = SourceType::New();
   source->SetSize(size);
 
   SpacingType spacing;
@@ -61,7 +61,7 @@ itkImageToVTKImageFilterTest(int, char *[])
   auto input = source->GetOutput();
   input->Print(std::cout);
 
-  ConnectorType::Pointer connector = ConnectorType::New();
+  auto connector = ConnectorType::New();
   connector->SetInput(input);
   connector->UpdateLargestPossibleRegion();
   connector->Update();

Modules/Bridge/VtkGlue/test/itkVTKImageToImageFilterTest.cxx

@@ -44,7 +44,7 @@ itkVTKImageToImageFilterTest(int, char *[])
 #endif
   input->Print(std::cout);
 
-  ConnectorType::Pointer connector = ConnectorType::New();
+  auto connector = ConnectorType::New();
   connector->SetInput(input);
   connector->Update();
 

Modules/Bridge/VtkGlue/test/itkVtkConnectedComponentImageFilterTest.cxx

@@ -76,7 +76,7 @@ itkVtkConnectedComponentImageFilterTest(int argc, char * argv[])
 
   using ReaderType = itk::ImageFileReader<InputImageType>;
 
-  ReaderType::Pointer reader = ReaderType::New();
+  auto reader = ReaderType::New();
   reader->SetFileName(argv[1]);
 
   QuickView viewer;
@@ -111,10 +111,10 @@ itkVtkConnectedComponentImageFilterTest(int argc, char * argv[])
     (*it).second->SetInput(reader->GetOutput());
     (*it).second->Update();
 
-    ConnectedComponentImageFilterType::Pointer connected = ConnectedComponentImageFilterType::New();
+    auto connected = ConnectedComponentImageFilterType::New();
     connected->SetInput((*it).second->GetOutput());
 
-    RGBFilterType::Pointer rgbFilter = RGBFilterType::New();
+    auto rgbFilter = RGBFilterType::New();
     rgbFilter->SetInput(connected->GetOutput());
     std::stringstream desc;
     desc << (*it).first << " threshold = " << (*it).second->GetThreshold();

Modules/Bridge/VtkGlue/test/itkVtkMedianFilterTest.cxx

@@ -45,11 +45,11 @@ itkVtkMedianFilterTest(int argc, char * argv[])
   using SubtractType = itk::SubtractImageFilter<ImageType>;
 
   // Create and setup a reader
-  ReaderType::Pointer reader = ReaderType::New();
+  auto reader = ReaderType::New();
   reader->SetFileName(inputFilename);
 
   // Create and setup a median filter
-  FilterType::Pointer       medianFilter = FilterType::New();
+  auto                      medianFilter = FilterType::New();
   FilterType::InputSizeType radius;
   radius.Fill(2);
   if (argc > 2)
@@ -60,7 +60,7 @@ itkVtkMedianFilterTest(int argc, char * argv[])
   medianFilter->SetRadius(radius);
   medianFilter->SetInput(reader->GetOutput());
 
-  SubtractType::Pointer diff = SubtractType::New();
+  auto diff = SubtractType::New();
   diff->SetInput1(reader->GetOutput());
   diff->SetInput2(medianFilter->GetOutput());
 

Modules/Compatibility/Deprecated/include/itkTreeIteratorBase.hxx

@@ -111,7 +111,7 @@ TreeIteratorBase<TTreeType>::Add(ValueType element)
     return false;
   }
 
-  typename TreeNodeType::Pointer node = TreeNodeType::New();
+  auto node = TreeNodeType::New();
   node->Set(element);
   m_Position->AddChild(node);
   m_Tree->Modified();
@@ -133,7 +133,7 @@ TreeIteratorBase<TTreeType>::Add(int itkNotUsed(childPosition), ValueType elemen
 {
   if (m_Position)
   {
-    typename TreeNodeType::Pointer node = TreeNodeType::New();
+    auto node = TreeNodeType::New();
     node->Set(element);
     m_Position->AddChild(node);
     m_Tree->Modified();
@@ -210,7 +210,7 @@ template <typename TTreeType>
 TTreeType *
 TreeIteratorBase<TTreeType>::GetSubTree() const
 {
-  typename TTreeType::Pointer tree = TTreeType::New();
+  auto tree = TTreeType::New();
   tree->SetRoot(m_Position);
   tree->SetSubtree(true);
   return tree;

Modules/Compatibility/Deprecated/test/itkTreeContainerTest.cxx

@@ -34,7 +34,7 @@ itkTreeContainerTest(int, char *[])
 {
   using NodeType = int;
   using TreeType = itk::TreeContainer<NodeType>;
-  TreeType::Pointer tree = TreeType::New();
+  auto tree = TreeType::New();
   tree->SetRoot(0);
   tree->Add(1, 0);
   tree->Add(2, 0);

Modules/Compatibility/Deprecated/test/itkTreeContainerTest2.cxx

@@ -192,10 +192,10 @@ CreateTree_1(NodeListType & internalList)
 {
   std::cout << "create tree" << std::endl;
 
-  TreeType::Pointer tree = TreeType::New();
+  auto tree = TreeType::New();
 
 
-  TreeChangeListener::Pointer treeChangeListener = TreeChangeListener::New();
+  auto                        treeChangeListener = TreeChangeListener::New();
   itk::TreeAddEvent<TreeType> ev;
   unsigned long               tag = tree->AddObserver(ev, treeChangeListener);
 
@@ -265,8 +265,8 @@ CreateTree_2(NodeListType & internalList)
 {
   std::cout << "create tree 2" << std::endl;
 
-  TreeType::Pointer tree = TreeType::New();
-  auto *            newNode = new TestData(9);
+  auto   tree = TreeType::New();
+  auto * newNode = new TestData(9);
   internalList.push_back(newNode);
   tree->SetRoot(newNode);
   itk::PostOrderTreeIterator<TreeType> it(tree);
@@ -399,7 +399,7 @@ itkTreeContainerTest2(int, char *[])
   result = IteratorTest(preOrderIt_Tree_1_2);
   testCounter += PrintResult(result, 3761);
 
-  TreeChangeListener::Pointer    treeChangeListener = TreeChangeListener::New();
+  auto                           treeChangeListener = TreeChangeListener::New();
   itk::TreeChangeEvent<TreeType> ev;
   unsigned long                  tag = tree->AddObserver(ev, treeChangeListener);
   tree->Clear();

Modules/Compatibility/Deprecated/test/itkVectorCentralDifferenceImageFunctionTest.cxx

@@ -27,7 +27,7 @@ itkVectorCentralDifferenceImageFunctionTest(int, char *[])
   using PixelType = itk::Vector<short, VectorDimension>;
   using ImageType = itk::Image<PixelType, ImageDimension>;
 
-  ImageType::Pointer  image = ImageType::New();
+  auto                image = ImageType::New();
   ImageType::SizeType size;
   size.Fill(16);
   ImageType::RegionType region(size);
@@ -50,7 +50,7 @@ itkVectorCentralDifferenceImageFunctionTest(int, char *[])
   // set up central difference calculator
   using CoordRepType = float;
   using FunctionType = itk::VectorCentralDifferenceImageFunction<ImageType, CoordRepType>;
-  FunctionType::Pointer function = FunctionType::New();
+  auto function = FunctionType::New();
 
   function->SetInputImage(image);
 

Modules/Compatibility/Deprecated/test/itkVectorResampleImageFilterTest.cxx

@@ -41,21 +41,21 @@ itkVectorResampleImageFilterTest(int argc, char * argv[])
 
   using FilterType = itk::VectorResampleImageFilter<ImageType, ImageType>;
 
-  FilterType::Pointer filter = FilterType::New();
+  auto filter = FilterType::New();
 
   ITK_EXERCISE_BASIC_OBJECT_METHODS(filter, VectorResampleImageFilter, ImageToImageFilter);
 
   itk::SimpleFilterWatcher watcher(filter);
 
   using InterpolatorType = itk::VectorLinearInterpolateImageFunction<ImageType, double>;
 
-  InterpolatorType::Pointer interpolator = InterpolatorType::New();
+  auto interpolator = InterpolatorType::New();
 
   filter->SetInterpolator(interpolator);
   ITK_TEST_SET_GET_VALUE(interpolator, filter->GetInterpolator());
 
   using TransformType = itk::IdentityTransform<double, Dimension>;
-  TransformType::Pointer transform = TransformType::New();
+  auto transform = TransformType::New();
 
   filter->SetTransform(transform);
   ITK_TEST_SET_GET_VALUE(transform, filter->GetTransform());
@@ -79,7 +79,7 @@ itkVectorResampleImageFilterTest(int argc, char * argv[])
   region.SetSize(size);
   region.SetIndex(start);
 
-  ImageType::Pointer image = ImageType::New();
+  auto image = ImageType::New();
 
   image->SetOrigin(origin);
   image->SetSpacing(spacing);
@@ -145,7 +145,7 @@ itkVectorResampleImageFilterTest(int argc, char * argv[])
 
   // Write an image for regression testing
   using WriterType = itk::ImageFileWriter<ImageType>;
-  WriterType::Pointer writer = WriterType::New();
+  auto writer = WriterType::New();
   writer->SetInput(filter->GetOutput());
   writer->SetFileName(argv[1]);
 

Modules/Core/Common/include/itkAnnulusOperator.hxx

@@ -92,8 +92,8 @@ AnnulusOperator<TPixel, TDimension, TAllocator>::GenerateCoefficients() -> Coeff
 
   // Use a couple of sphere spatial functions...
   using SphereType = SphereSpatialFunction<TDimension>;
-  typename SphereType::Pointer innerS = SphereType::New();
-  typename SphereType::Pointer outerS = SphereType::New();
+  auto innerS = SphereType::New();
+  auto outerS = SphereType::New();
 
   innerS->SetRadius(m_InnerRadius);
   outerS->SetRadius(m_InnerRadius + m_Thickness);

Modules/Core/Common/include/itkImageDuplicator.h

@@ -34,7 +34,7 @@ namespace itk
        medianFilter->Update();
        ImageType::Pointer image = medianFilter->GetOutput();
        using DuplicatorType = itk::ImageDuplicator< ImageType >;
-       DuplicatorType::Pointer duplicator = DuplicatorType::New();
+       auto duplicator = DuplicatorType::New();
        duplicator->SetInputImage(image);
        duplicator->Update();
        ImageType::Pointer clonedImage = duplicator->GetOutput();

Modules/Core/Common/include/itkImageSource.h

@@ -164,7 +164,7 @@ class ITK_TEMPLATE_EXPORT ImageSource
      \code
         // Setup the mini-pipeline to process the input to this filter
         // The input is not connected to the pipeline.
-        typename InputImageType::Pointer input = InputImageType::New();
+        auto input = InputImageType::New();
         input->Graft( const_cast< InputImageType * >( this->GetInput() );
         firstFilterInMiniPipeline->SetInput( input );
 

Modules/Core/Common/include/itkMacro.h

@@ -857,7 +857,7 @@ compilers.
       return;                                                                                                       \
     }                                                                                                               \
     CLANG_PRAGMA_POP                                                                                                \
-    typename DecoratorType::Pointer newInput = DecoratorType::New();                                                \
+    auto newInput = DecoratorType::New();                                                                           \
     newInput->Set(_arg);                                                                                            \
     this->Set##name##Input(newInput);                                                                               \
   }                                                                                                                 \
@@ -915,7 +915,7 @@ compilers.
     {                                                                                                         \
       return;                                                                                                 \
     }                                                                                                         \
-    typename DecoratorType::Pointer newInput = DecoratorType::New();                                          \
+    auto newInput = DecoratorType::New();                                                                     \
     newInput->Set(_arg);                                                                                      \
     this->Set##name##Input(newInput);                                                                         \
   }                                                                                                           \
@@ -1280,7 +1280,7 @@ compilers.
     }                                                                                                                \
     else                                                                                                             \
     {                                                                                                                \
-      typename DecoratorType::Pointer newOutput = DecoratorType::New();                                              \
+      auto newOutput = DecoratorType::New();                                                                         \
       newOutput->Set(_arg);                                                                                          \
       this->Set##name##Output(newOutput);                                                                            \
     }                                                                                                                \

Modules/Core/Common/include/itkOctree.hxx

@@ -270,7 +270,7 @@ Octree<TPixel, ColorTableSize, MappingFunctionType>::GetImage() -> ImageTypePoin
   typename ImageType::RegionType      region;
   region.SetSize(imageSize);
   region.SetIndex(imageIndex);
-  typename ImageType::Pointer img = ImageType::New();
+  auto img = ImageType::New();
   img->SetLargestPossibleRegion(region);
   img->SetBufferedRegion(region);
   img->SetRequestedRegion(region);

Modules/Core/Common/include/itkPointSetToImageFilter.hxx

@@ -124,7 +124,7 @@ PointSetToImageFilter<TInputPointSet, TOutputImage>::GenerateData()
                                       InputPointSetDimension,
                                       typename InputPointSetType::CoordRepType,
                                       typename InputPointSetType::PointsContainer>;
-  typename BoundingBoxType::Pointer bb = BoundingBoxType::New();
+  auto bb = BoundingBoxType::New();
   bb->SetPoints(InputPointSet->GetPoints());
   bb->ComputeBoundingBox();
 

Modules/Core/Common/include/itkSimpleFilterWatcher.h

@@ -47,7 +47,7 @@ namespace itk
  * Example of use:
  *
  * using FilterType = itk::BinaryThresholdImageFilter<ImageType>;
- * FilterType::Pointer thresholdFilter = FilterType::New();
+ * auto thresholdFilter = FilterType::New();
  *
  * SimpleFilterWatcher watcher(thresholdFilter, "Threshold");
  *

Modules/Core/Common/src/itkLoggerManager.cxx

@@ -23,7 +23,7 @@ namespace itk
 LoggerManager::LoggerPointer
 LoggerManager::CreateLogger(const NameType & name, PriorityLevelEnum level, PriorityLevelEnum levelForFlushing)
 {
-  Logger::Pointer logger = Logger::New();
+  auto logger = Logger::New();
 
   logger->SetName(name.c_str());
   logger->SetPriorityLevel(level);
@@ -36,7 +36,7 @@ LoggerManager::CreateLogger(const NameType & name, PriorityLevelEnum level, Prio
 LoggerManager::ThreadLoggerPointer
 LoggerManager::CreateThreadLogger(const NameType & name, PriorityLevelEnum level, PriorityLevelEnum levelForFlushing)
 {
-  ThreadLogger::Pointer logger = ThreadLogger::New();
+  auto logger = ThreadLogger::New();
 
   logger->SetName(name.c_str());
   logger->SetPriorityLevel(level);

Modules/Core/Common/src/itkObjectFactoryBase.cxx

@@ -425,7 +425,7 @@ NameIsSharedLibrary(const char * name)
 void
 ObjectFactoryBase::LoadLibrariesInPath(const char * path)
 {
-  Directory::Pointer dir = Directory::New();
+  auto dir = Directory::New();
 
   if (!dir->Load(path))
   {

Modules/Core/Common/test/itkAbortProcessObjectTest.cxx

@@ -61,7 +61,7 @@ itkAbortProcessObjectTest(int, char *[])
 {
   // type alias to simplify the syntax
   using ShortImage = itk::Image<short, 2>;
-  ShortImage::Pointer img = ShortImage::New();
+  auto img = ShortImage::New();
 
   // fill in an image
   const ShortImage::IndexType index = { { 0, 0 } };