COMP: Future proof code for null pointer robustness

Prior to C++11 the NULL macro expanded to different integer types on different compilers (sometimes size_t 0, usually unsigned long 0). C++11 provides a keyword nullptr to more robustly identify a null pointer. This robust null pointer (i.e. NOT an integer) allows for more comprehensive type checking that is utilized in ITKv5. As a consequence, implicit type conversion from integers (a.k.a NULL) for smart pointers can cause compiler ambiguities in ITKv5 with C++11 enhanced pointer checking. Using ITK_NULLPTR allows both ITKv4 and ITKv5 to compile and behave as expected. When building: ITKv4 & CXX_STANDARD=98, ITK_NULLPTR -> NULL (smartpointers can be initialized with integers like NULL) ITKv4 & CXX_STANDARD=11, ITK_NULLPTR -> nullptr (prefer initializing smartpointers with nullptr, but NULL also works) ITKv5 & CXX_STANDARD=11, ITK_NULLPTR -> nullptr (nullptr required for initializing smartpointers)
gandreadis · Mar 28, 2018 · 576df61 · 576df61
1 parent c95e77a
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Showing 127 changed files with 356 additions and 356 deletions.
diff --git a/Examples/ANTS.cxx b/Examples/ANTS.cxx
@@ -107,7 +107,7 @@ int ANTSex(int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ANTS( std::vector<std::string> args, std::ostream* /*out_stream = NULL*/ )
+int ANTS( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR*/ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;
@@ -279,7 +279,7 @@ int ANTS( std::vector<std::string> args, std::ostream* /*out_stream = NULL*/ )
       pos = delimPos + 1;
       }
 
-    char * *     my_argv = NULL;
+    char * *     my_argv = ITK_NULLPTR;
     if( my_argc > 0 )
       {
       unsigned int arg_count = 0;

diff --git a/Examples/ANTSConformalMapping.cxx b/Examples/ANTSConformalMapping.cxx
@@ -206,9 +206,9 @@ int ANTSConformalMapping( itk::ants::CommandLineParser *parser )
   // we define the options in the InitializeCommandLineOptions function
   // and then use them here ...
   typedef vtkPolyData MeshType;
-  vtkSmartPointer<MeshType> labelmesh = NULL;
-  vtkSmartPointer<MeshType> featuremesh = NULL;
-  vtkSmartPointer<MeshType> inflatedmesh = NULL;
+  vtkSmartPointer<MeshType> labelmesh = ITK_NULLPTR;
+  vtkSmartPointer<MeshType> featuremesh = ITK_NULLPTR;
+  vtkSmartPointer<MeshType> inflatedmesh = ITK_NULLPTR;
   typedef itk::FEMDiscConformalMap<MeshType, ImageType> ParamType;
   typename ParamType::Pointer flattener = ParamType::New();
   flattener->SetDebug(false);
@@ -403,7 +403,7 @@ int ANTSConformalMapping( itk::ants::CommandLineParser *parser )
     }
 
   // do stuff -- but not implemented yet
-  //   flattener->SetDiscBoundaryList(NULL);
+  //   flattener->SetDiscBoundaryList(ITK_NULLPTR);
 
   std::cout << " you will flatten " << labeltoflatten << ".  param while searching? " << paramws << std::endl;
   flattener->SetSigma(1);
@@ -470,7 +470,7 @@ int ANTSConformalMapping( itk::ants::CommandLineParser *parser )
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ANTSConformalMapping( std::vector<std::string> args, std::ostream* out_stream = NULL )
+int ANTSConformalMapping( std::vector<std::string> args, std::ostream* out_stream = ITK_NULLPTR )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ANTSIntegrateVectorField.cxx b/Examples/ANTSIntegrateVectorField.cxx
@@ -397,7 +397,7 @@ int IntegrateVectorField(int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ANTSIntegrateVectorField( std::vector<std::string> args, std::ostream* /*out_stream = NULL*/ )
+int ANTSIntegrateVectorField( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR*/ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ANTSIntegrateVelocityField.cxx b/Examples/ANTSIntegrateVelocityField.cxx
@@ -112,7 +112,7 @@ int IntegrateVelocityField(int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ANTSIntegrateVelocityField( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int ANTSIntegrateVelocityField( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ANTSJacobian.cxx b/Examples/ANTSJacobian.cxx
@@ -534,7 +534,7 @@ int Jacobian(int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ANTSJacobian( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int ANTSJacobian( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ANTSUseDeformationFieldToGetAffineTransform.cxx b/Examples/ANTSUseDeformationFieldToGetAffineTransform.cxx
@@ -415,7 +415,7 @@ typedef itk::Rigid2DTransform< double > TransformType;
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ANTSUseDeformationFieldToGetAffineTransform( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int ANTSUseDeformationFieldToGetAffineTransform( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ANTSUseLandmarkImagesToGetAffineTransform.cxx b/Examples/ANTSUseLandmarkImagesToGetAffineTransform.cxx
@@ -367,7 +367,7 @@ int LandmarkBasedTransformInitializerBA(int, char * argv[])
   return EXIT_SUCCESS;
 }
 
-int ANTSUseLandmarkImagesToGetAffineTransform( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int ANTSUseLandmarkImagesToGetAffineTransform( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ANTSUseLandmarkImagesToGetBSplineDisplacementField.cxx b/Examples/ANTSUseLandmarkImagesToGetBSplineDisplacementField.cxx
@@ -468,7 +468,7 @@ int LandmarkBasedDisplacementFieldTransformInitializer( int argc, char *argv[] )
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ANTSUseLandmarkImagesToGetBSplineDisplacementField( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int ANTSUseLandmarkImagesToGetBSplineDisplacementField( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/Atropos.cxx b/Examples/Atropos.cxx
@@ -1658,7 +1658,7 @@ void AtroposInitializeCommandLineOptions( itk::ants::CommandLineParser *parser )
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int Atropos( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int Atropos( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/AverageAffineTransform.cxx b/Examples/AverageAffineTransform.cxx
@@ -96,7 +96,7 @@ static bool AverageAffineTransform_ParseInput(int argc, char * *argv, char *& ou
     ind++;
     }
 
-//    if (reference_image_filename == NULL) {
+//    if (reference_image_filename == ITK_NULLPTR) {
 //        std::cout << "the reference image file (-R) must be given!!!"
 //        << std::endl;
 //        return false;
@@ -226,7 +226,7 @@ void AverageAffineTransform(char *output_affine_txt, char *reference_affine_txt,
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int AverageAffineTransform( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int AverageAffineTransform( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/AverageAffineTransformNoRigid.cxx b/Examples/AverageAffineTransformNoRigid.cxx
@@ -96,7 +96,7 @@ static bool AverageAffineTransformNoRigid_ParseInput(int argc, char * *argv, cha
     ind++;
     }
 
-//    if (reference_image_filename == NULL) {
+//    if (reference_image_filename == ITK_NULLPTR) {
 //        std::cout << "the reference image file (-R) must be given!!!"
 //        << std::endl;
 //        return false;
@@ -225,7 +225,7 @@ void AverageAffineTransformNoRigid(char *output_affine_txt, char *reference_affi
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int AverageAffineTransformNoRigid( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int AverageAffineTransformNoRigid( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/AverageImages.cxx b/Examples/AverageImages.cxx
@@ -258,7 +258,7 @@ int AverageImages(unsigned int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int AverageImages( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int AverageImages( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/AverageTensorImages.cxx b/Examples/AverageTensorImages.cxx
@@ -87,7 +87,7 @@ int AverageTensorImages(unsigned int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int AverageTensorImages( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int AverageTensorImages( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ClusterImageStatistics.cxx b/Examples/ClusterImageStatistics.cxx
@@ -282,7 +282,7 @@ int  ClusterStatistics(unsigned int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ClusterImageStatistics( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int ClusterImageStatistics( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ComposeMultiTransform.cxx b/Examples/ComposeMultiTransform.cxx
@@ -66,7 +66,7 @@ static bool ComposeMultiTransform_ParseInput(int argc, char * *argv, char *& out
     ind++;
     }
 
-//    if (reference_image_filename == NULL) {
+//    if (reference_image_filename == ITK_NULLPTR) {
 //        std::cout << "the reference image file (-R) must be given!!!"
 //        << std::endl;
 //        return false;
@@ -284,7 +284,7 @@ void ComposeMultiAffine(char *output_affine_txt,
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ComposeMultiTransform( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int ComposeMultiTransform( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;
@@ -361,7 +361,7 @@ int ComposeMultiTransform( std::vector<std::string> args, std::ostream* /*out_st
     }
 
   TRAN_OPT_QUEUE opt_queue;
-  //    char *moving_image_filename = NULL;
+  //    char *moving_image_filename = ITK_NULLPTR;
   char *output_image_filename = ITK_NULLPTR;
   char *reference_image_filename = ITK_NULLPTR;
 

diff --git a/Examples/CompositeTransformUtil.cxx b/Examples/CompositeTransformUtil.cxx
@@ -167,7 +167,7 @@ static int Assemble(const std::string & CompositeName,
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int CompositeTransformUtil( std::vector<std::string> args, std::ostream* /*out_stream = NULL */)
+int CompositeTransformUtil( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */)
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ComputeSimilarityMetric.cxx b/Examples/ComputeSimilarityMetric.cxx
@@ -59,9 +59,9 @@ int ComputeSimilarityMetric(int argc, char *argv[])
     }
   argct++;
 
-  typename ImageType::Pointer image1 = NULL;
+  typename ImageType::Pointer image1 = ITK_NULLPTR;
   ReadImage<ImageType>(image1, fn1.c_str() );
-  typename ImageType::Pointer image2 = NULL;
+  typename ImageType::Pointer image2 = ITK_NULLPTR;
   ReadImage<ImageType>(image2, fn2.c_str() );
 
 /*
@@ -209,7 +209,7 @@ int ComputeSimilarityMetric(int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ComputeSimilarityMetric( std::vector<std::string> args, std::ostream* out_stream = NULL )
+int ComputeSimilarityMetric( std::vector<std::string> args, std::ostream* out_stream = ITK_NULLPTR )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ConformalMapping.cxx b/Examples/ConformalMapping.cxx
@@ -864,7 +864,7 @@ vtkwriter->Write();
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ConformalMapping( std::vector<std::string> args, std::ostream* out_stream = NULL )
+int ConformalMapping( std::vector<std::string> args, std::ostream* out_stream = ITK_NULLPTR )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ConvertImage.cxx b/Examples/ConvertImage.cxx
@@ -171,7 +171,7 @@ int ConvertImage( int argc, char *argv[] )
     bool isRescaleType = false;
     for( unsigned int i = 0; i < rescaleFileTypes.size(); i++ )
       {
-      if( strstr( argv[3], rescaleFileTypes[i].c_str() ) != NULL )
+      if( strstr( argv[3], rescaleFileTypes[i].c_str() ) != ITK_NULLPTR )
         {
         isRescaleType = true;
         break;
@@ -203,7 +203,7 @@ int ConvertImage( int argc, char *argv[] )
   return EXIT_SUCCESS;
 }
 
-int ConvertImage( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int ConvertImage( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ConvertImagePixelType.cxx b/Examples/ConvertImagePixelType.cxx
@@ -90,7 +90,7 @@ int ConvertType(int argc, char *argv[], double MINVAL, double MAXVAL)
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ConvertImagePixelType( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int ConvertImagePixelType( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ConvertInputImagePixelTypeToFloat.cxx b/Examples/ConvertInputImagePixelTypeToFloat.cxx
@@ -74,7 +74,7 @@ int ConvertTypeToFloat( int argc, char *argv[] )
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ConvertInputImagePixelTypeToFloat( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int ConvertInputImagePixelTypeToFloat( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ConvertScalarImageToRGB.cxx b/Examples/ConvertScalarImageToRGB.cxx
@@ -326,7 +326,7 @@ int ConvertScalarImageToRGB( int argc, char *argv[] )
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ConvertScalarImageToRGB( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int ConvertScalarImageToRGB( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ConvertToJpg.cxx b/Examples/ConvertToJpg.cxx
@@ -88,7 +88,7 @@ int ConvertType(int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ConvertToJpg( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int ConvertToJpg( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   try
     {

diff --git a/Examples/ConvertTransformFile.cxx b/Examples/ConvertTransformFile.cxx
@@ -447,7 +447,7 @@ int ConvertTransformFile(int argc, char* argv[])
 /*
  *
  */
-int ConvertTransformFile( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int ConvertTransformFile( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/ConvertVectorFieldToVTK.cxx b/Examples/ConvertVectorFieldToVTK.cxx
@@ -29,7 +29,7 @@ namespace ants
 {
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int ConvertVectorFieldToVTK( std::vector<std::string> args, std::ostream* out_stream = NULL )
+int ConvertVectorFieldToVTK( std::vector<std::string> args, std::ostream* out_stream = ITK_NULLPTR )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/CopyImageHeaderInformation.cxx b/Examples/CopyImageHeaderInformation.cxx
@@ -122,7 +122,7 @@ int CopyImageHeaderInformation(int argc, char *argv[])
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int CopyImageHeaderInformation( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int CopyImageHeaderInformation( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/CreateDTICohort.cxx b/Examples/CreateDTICohort.cxx
@@ -1065,7 +1065,7 @@ void InitializeCommandLineOptions( itk::ants::CommandLineParser *parser )
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int CreateDTICohort( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int CreateDTICohort( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/CreateDisplacementField.cxx b/Examples/CreateDisplacementField.cxx
@@ -134,7 +134,7 @@ void CreateDisplacementField( int argc, char *argv[] )
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int CreateDisplacementField( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int CreateDisplacementField( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/CreateImage.cxx b/Examples/CreateImage.cxx
@@ -245,7 +245,7 @@ int CreateZeroImage( int argc, char *argv[] )
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int CreateImage( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int CreateImage( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;

diff --git a/Examples/CreateTiledMosaic.cxx b/Examples/CreateTiledMosaic.cxx
@@ -1199,7 +1199,7 @@ void InitializeCommandLineOptions( itk::ants::CommandLineParser *parser )
 
 // entry point for the library; parameter 'args' is equivalent to 'argv' in (argc,argv) of commandline parameters to
 // 'main()'
-int CreateTiledMosaic( std::vector<std::string> args, std::ostream* /*out_stream = NULL */ )
+int CreateTiledMosaic( std::vector<std::string> args, std::ostream* /*out_stream = ITK_NULLPTR */ )
 {
   // put the arguments coming in as 'args' into standard (argc,argv) format;
   // 'args' doesn't have the command name as first, argument, so add it manually;