Use nullptr instead of NULL in the code and documentation

This is a combination of running clang-tidy with modernize-use-nullptr
check for some ports (GTK, X11, OSX) and manual changes to the ports for
which it couldn't be used easily (MSW, DFB) and also manually updating
the docs.

Also replace NULL with null or nullptr in the comments as this is more
consistent with the use of nullptr in the code and makes it simpler to
grep for the remaining occurrences of NULL itself.

And also use null in the assert messages.

Only a few occurrences of "NULL" are still left in non-C files, mostly
corresponding to unclear comments or string output which it might not be
safe to change.

build/bakefiles/wxpresets/sample/minimal.cpp

@@ -129,7 +129,7 @@ bool MyApp::OnInit()
 
 // frame constructor
 MyFrame::MyFrame(const wxString& title)
-       : wxFrame(NULL, wxID_ANY, title)
+       : wxFrame(nullptr, wxID_ANY, title)
 {
     // set the frame icon
 

demos/bombs/bombs.cpp

@@ -32,7 +32,7 @@ wxIMPLEMENT_APP(BombsApp);
 // Called to initialize the program
 bool BombsApp::OnInit()
 {
-    srand((unsigned) time(NULL));
+    srand((unsigned) time(nullptr));
 
     m_frame = new BombsFrame(&m_game);
 
@@ -52,7 +52,7 @@ wxBEGIN_EVENT_TABLE(BombsFrame, wxFrame)
 wxEND_EVENT_TABLE()
 
 BombsFrame::BombsFrame(BombsGame *game)
-    : wxFrame(NULL, wxID_ANY, wxT("wxBombs"), wxDefaultPosition,
+    : wxFrame(nullptr, wxID_ANY, wxT("wxBombs"), wxDefaultPosition,
         wxSize(300, 300), wxDEFAULT_DIALOG_STYLE|wxMINIMIZE_BOX)
 {
     m_game = game;
@@ -248,7 +248,7 @@ BombsCanvas::BombsCanvas(wxFrame *parent, BombsGame *game)
     m_cellWidth = (sx+3+X_UNIT)/X_UNIT;
     m_cellHeight = (sy+3+Y_UNIT)/Y_UNIT;
     dc.SetMapMode(wxMM_TEXT);
-    m_bmp = NULL;
+    m_bmp = nullptr;
 }
 
 BombsCanvas::~BombsCanvas()
@@ -256,7 +256,7 @@ BombsCanvas::~BombsCanvas()
     if (m_bmp)
     {
         delete m_bmp;
-        m_bmp = NULL;
+        m_bmp = nullptr;
     }
 }
 
@@ -302,7 +302,7 @@ void BombsCanvas::UpdateGridSize()
     if (m_bmp)
     {
         delete m_bmp;
-        m_bmp = NULL;
+        m_bmp = nullptr;
     }
     SetSize(GetGridSizeInPixels());
     Refresh();

demos/bombs/game.h

@@ -26,7 +26,7 @@ public:
     BombsGame()
     {
         m_width = m_height = 0;
-        m_field = NULL;
+        m_field = nullptr;
     }
 
     ~BombsGame();

demos/forty/game.cpp

@@ -179,7 +179,7 @@ void Game::DoMove(wxDC& dc, Pile* src, Pile* dest)
     if (HaveYouWon())
     {
         wxWindow *frame = wxTheApp->GetTopWindow();
-        wxWindow *canvas = (wxWindow *) NULL;
+        wxWindow *canvas = nullptr;
 
         if (frame)
         {

demos/forty/pile.cpp

@@ -57,7 +57,7 @@ Pile::Pile(int x, int y, int dx, int dy)
 //+-------------------------------------------------------------+
 //| Description:                                                |
 //| Redraw the pile on the screen. If the pile is empty         |
-//| just draw a NULL card as a place holder for the pile.       |
+//| just draw a null card as a place holder for the pile.       |
 //| Otherwise draw the pile from the bottom up, starting        |
 //| at the origin of the pile, shifting each subsequent         |
 //| card by the pile's x and y offsets.                         |
@@ -65,7 +65,7 @@ Pile::Pile(int x, int y, int dx, int dy)
 void Pile::Redraw(wxDC& dc )
 {
     FortyFrame *frame = (FortyFrame*) wxTheApp->GetTopWindow();
-    wxWindow *canvas = (wxWindow *) NULL;
+    wxWindow *canvas = nullptr;
     if (frame)
     {
         canvas = frame->GetCanvas();
@@ -103,7 +103,7 @@ void Pile::Redraw(wxDC& dc )
 //| Pile::GetTopCard()                                          |
 //+-------------------------------------------------------------+
 //| Description:                                                |
-//| Return a pointer to the top card in the pile or NULL        |
+//| Return a pointer to the top card in the pile or nullptr     |
 //| if the pile is empty.                                       |
 //| NB: Gets a copy of the card without removing it from the    |
 //| pile.                                                       |
@@ -126,7 +126,7 @@ Card* Pile::GetTopCard()
 //| Description:                                                |
 //| If the pile is not empty, remove the top card from the      |
 //| pile and return the pointer to the removed card.            |
-//| If the pile is empty return a NULL pointer.                 |
+//| If the pile is empty return a null pointer.                 |
 //+-------------------------------------------------------------+
 Card* Pile::RemoveTopCard()
 {
@@ -229,7 +229,7 @@ int Pile::CalcDistance(int x, int y)
 
 // Return the card at x, y. Check the top card first, then
 // work down the pile. If a card is found then return a pointer
-// to the card, otherwise return NULL
+// to the card, otherwise return nullptr
 Card* Pile::GetCard(int x, int y)
 {
     int cardX;

demos/fractal/fractal.cpp

@@ -40,12 +40,12 @@ hack doesn't fix.
 #include <time.h>
 
 #define Random(x) (rand() % x)
-#define Randomize() (srand((unsigned int)time(NULL)))
+#define Randomize() (srand((unsigned int)time(nullptr)))
 
 static int detail = 9; // CHANGE THIS... 7,8,9 etc
 
 static bool running = false;
-static wxMenuBar *menuBar = NULL;
+static wxMenuBar *menuBar = nullptr;
 
 // Define a new application type
 class MyApp: public wxApp
@@ -89,7 +89,7 @@ private:
 bool MyApp::OnInit()
 {
   // Create the main frame window
-  MyFrame *frame = new MyFrame(NULL, wxT("Fractal Mountains for wxWidgets"), wxDefaultPosition, wxSize(640, 480));
+  MyFrame *frame = new MyFrame(nullptr, wxT("Fractal Mountains for wxWidgets"), wxDefaultPosition, wxSize(640, 480));
 
   // Make a menubar
   wxMenu *file_menu = new wxMenu;

demos/life/dialogs.cpp

@@ -89,7 +89,7 @@ LifeSamplesDialog::LifeSamplesDialog(wxWindow *parent)
     m_list = new wxListBox( this, ID_LISTBOX,
         wxDefaultPosition,
         listSize,
-        0, NULL,
+        0, nullptr,
         wxLB_SINGLE | wxLB_NEEDED_SB | wxLB_HSCROLL );
 
     for (unsigned i = 0; i < (sizeof(g_patterns) / sizeof(LifePattern)); i++)

demos/life/game.cpp

@@ -112,10 +112,10 @@ Life::Life()
     // pattern data
     m_numcells    = 0;
     m_boxes       = new LifeCellBox *[HASHSIZE];
-    m_head        = NULL;
+    m_head        = nullptr;
-    m_available   = NULL;
+    m_available   = nullptr;
     for (int i = 0; i < HASHSIZE; i++)
-        m_boxes[i] = NULL;
+        m_boxes[i] = nullptr;
 
     // state vars for BeginFind & FindMore
     m_cells       = new LifeCell[CELLSARRAYSIZE];
@@ -141,7 +141,7 @@ void Life::Clear()
 
     // clear the hash table pointers
     for (int i = 0; i < HASHSIZE; i++)
-        m_boxes[i] = NULL;
+        m_boxes[i] = nullptr;
 
     // free used boxes
     c = m_head;
@@ -151,7 +151,7 @@ void Life::Clear()
         delete c;
         c = nc;
     }
-    m_head = NULL;
+    m_head = nullptr;
 
     // free available boxes
     c = m_available;
@@ -161,7 +161,7 @@ void Life::Clear()
         delete c;
         c = nc;
     }
-    m_available = NULL;
+    m_available = nullptr;
 
     // reset state
     m_name        = wxEmptyString;
@@ -295,7 +295,7 @@ LifeCellBox* Life::CreateBox(wxInt32 x, wxInt32 y, wxUint32 hv)
 
 // LinkBox:
 //  Returns a pointer to the box (x, y); if it didn't exist yet,
-//  it returns NULL or creates a new one, depending on the value
+//  it returns nullptr or creates a new one, depending on the value
 //  of the 'create' parameter.
 //
 LifeCellBox* Life::LinkBox(wxInt32 x, wxInt32 y, bool create)
@@ -312,7 +312,7 @@ LifeCellBox* Life::LinkBox(wxInt32 x, wxInt32 y, bool create)
         if ((c->m_x == x) && (c->m_y == y)) return c;
 
     // if not found, and (create == true), create a new one
-    return create? CreateBox(x, y, hv) : (LifeCellBox*) NULL;
+    return create? CreateBox(x, y, hv) : nullptr;
 }
 
 // KillBox:
@@ -338,10 +338,10 @@ void Life::KillBox(LifeCellBox *c)
     // update neighbours
     if (c->m_next) c->m_next->m_prev = c->m_prev;
     if (c->m_hnext) c->m_hnext->m_hprev = c->m_hprev;
-    if (c->m_up) c->m_up->m_dn = NULL;
+    if (c->m_up) c->m_up->m_dn = nullptr;
-    if (c->m_dn) c->m_dn->m_up = NULL;
+    if (c->m_dn) c->m_dn->m_up = nullptr;
-    if (c->m_lf) c->m_lf->m_rt = NULL;
+    if (c->m_lf) c->m_lf->m_rt = nullptr;
-    if (c->m_rt) c->m_rt->m_lf = NULL;
+    if (c->m_rt) c->m_rt->m_lf = nullptr;
 
     // append to the list of available boxes
     c->m_next = m_available;
@@ -515,7 +515,7 @@ bool Life::FindMore(LifeCell *cells[], size_t *ncells)
         for ( ; m_y <= m_y1; m_y += 8, m_x = m_x0)
             for ( ; m_x <= m_x1; m_x += 8)
             {
-                if ((c = LinkBox(m_x, m_y, false)) == NULL)
+                if ((c = LinkBox(m_x, m_y, false)) == nullptr)
                     continue;
 
                 // check whether there is enough space left in the array
@@ -540,7 +540,7 @@ bool Life::FindMore(LifeCell *cells[], size_t *ncells)
         for ( ; m_y <= m_y1; m_y += 8, m_x = m_x0)
             for ( ; m_x <= m_x1; m_x += 8)
             {
-                if ((c = LinkBox(m_x, m_y, false)) == NULL)
+                if ((c = LinkBox(m_x, m_y, false)) == nullptr)
                     continue;
 
                 // check whether there is enough space left in the array

demos/life/life.cpp

@@ -173,8 +173,8 @@ bool LifeApp::OnInit()
 
 // frame constructor
 LifeFrame::LifeFrame() :
-  wxFrame( (wxFrame *) NULL, wxID_ANY, _("Life!"), wxDefaultPosition ),
+  wxFrame( nullptr, wxID_ANY, _("Life!"), wxDefaultPosition ),
-  m_navigator(NULL)
+  m_navigator(nullptr)
 {
     // frame icon
     SetIcon(wxICON(mondrian));
@@ -1104,12 +1104,12 @@ void LifeCanvas::OnScroll(wxScrollWinEvent& event)
     if (orient == wxHORIZONTAL)
     {
         m_viewportX += scrollinc;
-        ScrollWindow( -m_cellsize * scrollinc, 0, (const wxRect *) NULL);
+        ScrollWindow( -m_cellsize * scrollinc, 0, nullptr);
     }
     else
     {
         m_viewportY += scrollinc;
-        ScrollWindow( 0, -m_cellsize * scrollinc, (const wxRect *) NULL);
+        ScrollWindow( 0, -m_cellsize * scrollinc, nullptr);
     }
 }
 

demos/poem/wxpoem.cpp

@@ -62,8 +62,8 @@ static int      XPos;                           // Startup X position
 static int      YPos;                           // Startup Y position
 static int      pointSize = 12;                 // Font size
 
-static const wxChar   *index_filename = NULL;            // Index filename
+static const wxChar   *index_filename = nullptr;            // Index filename
-static const wxChar   *data_filename = NULL;             // Data filename
+static const wxChar   *data_filename = nullptr;             // Data filename
 static wxChar   error_buf[300];                 // Error message buffer
 static bool     loaded_ok = false;              // Poem loaded ok
 static bool     index_ok = false;               // Index loaded ok
@@ -72,7 +72,7 @@ static bool     paging = false;                 // Are we paging?
 static int      current_page = 0;               // Currently viewed page
 
 // Backing bitmap
-wxBitmap        *backingBitmap = NULL;
+wxBitmap        *backingBitmap = nullptr;
 
 void            PoetryError(const wxChar *, const wxChar *caption=wxT("wxPoem Error"));
 void            PoetryNotify(const wxChar *Msg, const wxChar *caption=wxT("wxPoem"));
@@ -90,7 +90,7 @@ void            FindMax(int *max_thing, int thing);
 
 wxIMPLEMENT_APP(MyApp);
 
-MainWindow *TheMainWindow = NULL;
+MainWindow *TheMainWindow = nullptr;
 
 // Create the fonts
 void MainWindow::CreateFonts()
@@ -110,7 +110,7 @@ MainWindow::MainWindow(wxFrame *frame, wxWindowID id, const wxString& title,
      const wxPoint& pos, const wxSize& size, long style):
      wxFrame(frame, id, title, pos, size, style)
 {
-    m_corners[0] = m_corners[1] = m_corners[2] = m_corners[3] = NULL;
+    m_corners[0] = m_corners[1] = m_corners[2] = m_corners[3] = nullptr;
 
     ReadPreferences();
     CreateFonts();
@@ -510,7 +510,7 @@ bool MyApp::OnInit()
 //    randomize();
     pages[0] = 0;
 
-    TheMainWindow = new MainWindow(NULL,
+    TheMainWindow = new MainWindow(nullptr,
                                    wxID_ANY,
                                    wxT("wxPoem"),
                                    wxPoint(XPos, YPos),
@@ -592,7 +592,7 @@ MyCanvas::~MyCanvas()
     // Note: this must be done before the main window/canvas are destroyed
     // or we get an error (no parent window for menu item button)
     delete m_popupMenu;
-    m_popupMenu = NULL;
+    m_popupMenu = nullptr;
 }
 
 // Define the repainting behaviour
@@ -693,13 +693,13 @@ int LoadIndex(const wxChar *file_name)
 
     wxChar buf[100];
 
-    if (file_name == NULL)
+    if (file_name == nullptr)
         return 0;
 
     wxSprintf(buf, wxT("%s.idx"), file_name);
 
     index_file = wxFopen(buf, wxT("r"));
-    if (index_file == NULL)
+    if (index_file == nullptr)
         return 0;
 
     wxFscanf(index_file, wxT("%ld"), &nitems);
@@ -769,7 +769,7 @@ bool LoadPoem(const wxChar *file_name, long position)
     paging = false;
     current_page = 0;
 
-    if (file_name == NULL)
+    if (file_name == nullptr)
     {
       wxSprintf(error_buf, wxT("Error in Poem loading."));
       PoetryError(error_buf);
@@ -779,7 +779,7 @@ bool LoadPoem(const wxChar *file_name, long position)
     wxSprintf(buf, wxT("%s.dat"), file_name);
     data_file = wxFopen(buf, wxT("rb"));
 
-    if (data_file == NULL)
+    if (data_file == nullptr)
     {
       wxSprintf(error_buf, wxT("Data file %s not found."), buf);
       PoetryError(error_buf);

distrib/autopackage/sample/minimal.cpp

@@ -129,7 +129,7 @@ bool MyApp::OnInit()
 
 // frame constructor
 MyFrame::MyFrame(const wxString& title)
-       : wxFrame(NULL, wxID_ANY, title)
+       : wxFrame(nullptr, wxID_ANY, title)
 {
     // set the frame icon
 

docs/contributing/how-to-add-class-documentation.md

@@ -73,7 +73,7 @@ DO:
   It's also very important to make a consistent use of the ALIASES
   defined by wxWidgets' Doxyfile. Open that file for more info.
 
-- when you write true, false and NULL with their C++ semantic meaning,
+- when you write true, false and nullptr with their C++ semantic meaning,
   then use the @true, @false and @NULL commands.
 
 - separate different paragraphs with an empty comment line.

docs/doxygen/Doxyfile

@@ -140,7 +140,7 @@ ALIASES += header{1}="Include file:^^ \verbatim #include <\1> \endverbatim"
 # some formatting aliases
 ALIASES += true="<span class='literal'>true</span>"
 ALIASES += false="<span class='literal'>false</span>"
-ALIASES += NULL="<span class='literal'>NULL</span>"
+ALIASES += NULL="<span class='literal'>nullptr</span>"
 ALIASES += NUL="<span class='literal'>NUL</span>"
 
 # NOTE: these are important as you can't write in the docs

docs/doxygen/mainpages/samples.h

@@ -189,7 +189,7 @@ See @ref overview_config for the descriptions of all features of this class.
 
 This sample shows how to use wxDebugReport class to
 generate a debug report in case of a program crash or otherwise. On start up,
-it proposes to either crash itself (by dereferencing a NULL pointer) or
+it proposes to either crash itself (by dereferencing a @NULL) or
 generate debug report without doing it. Next it initializes the debug report
 with standard information adding a custom file to it (just a timestamp) and
 allows to view the information gathered using

docs/doxygen/overviews/app.h

@@ -45,7 +45,7 @@ wxIMPLEMENT_APP(DerivedApp);
 
 bool DerivedApp::OnInit()
 {
-    wxFrame *the_frame = new wxFrame(NULL, ID_MYFRAME, argv[0]);
+    wxFrame *the_frame = new wxFrame(nullptr, ID_MYFRAME, argv[0]);
     ...
     the_frame->Show(true);
 

docs/doxygen/overviews/archive.h

@@ -73,7 +73,7 @@ auto_ptr<wxZipEntry> entry;
 wxFFileInputStream in(wxT("test.zip"));
 wxZipInputStream zip(in);
 
-while (entry.reset(zip.GetNextEntry()), entry.get() != NULL)
+while (entry.reset(zip.GetNextEntry()), entry.get() != nullptr)
 {
     // access meta-data
     wxString name = entry->GetName();
@@ -114,7 +114,7 @@ auto_ptr<wxZipEntry> entry;
 outzip.CopyArchiveMetaData(inzip);
 
 // call CopyEntry for each entry except those matching the pattern
-while (entry.reset(inzip.GetNextEntry()), entry.get() != NULL)
+while (entry.reset(inzip.GetNextEntry()), entry.get() != nullptr)
     if (!entry->GetName().Matches(wxT("*.txt")))
         if (!outzip.CopyEntry(entry.release(), inzip))
             break;
@@ -165,9 +165,9 @@ do
 {
     entry.reset(zip.GetNextEntry());
 }
-while (entry.get() != NULL && entry->GetInternalName() != name);
+while (entry.get() != nullptr && entry->GetInternalName() != name);
 
-if (entry.get() != NULL)
+if (entry.get() != nullptr)
 {
     // read the entry's data...
 }
@@ -189,7 +189,7 @@ wxFFileInputStream in(wxT("test.zip"));
 wxZipInputStream zip(in);
 
 // load the zip catalog
-while ((entry = zip.GetNextEntry()) != NULL)
+while ((entry = zip.GetNextEntry()) != nullptr)
 {
     wxZipEntry*& current = cat[entry->GetInternalName()];
     // some archive formats can have multiple entries with the same name
@@ -296,7 +296,7 @@ if (in->IsOk())
         auto_ptr<wxArchiveEntry> entry;
 
         // list the contents of the archive
-        while ((entry.reset(arc->GetNextEntry())), entry.get() != NULL)
+        while ((entry.reset(arc->GetNextEntry())), entry.get() != nullptr)
             std::wcout << entry->GetName() << "\n";
     }
     else
@@ -381,7 +381,7 @@ auto_ptr<wxArchiveEntry> entry;
 
 outarc->CopyArchiveMetaData(*arc);
 
-while (entry.reset(arc->GetNextEntry()), entry.get() != NULL)
+while (entry.reset(arc->GetNextEntry()), entry.get() != nullptr)
 {
     if (entry->GetName() == from)
         entry->SetName(to);
@@ -418,7 +418,7 @@ MyNotifier notifier;
 
 outarc->CopyArchiveMetaData(*arc);
 
-while (entry.reset(arc->GetNextEntry()), entry.get() != NULL)
+while (entry.reset(arc->GetNextEntry()), entry.get() != nullptr)
 {
     entry->SetNotifier(notifier);
     if (!outarc->CopyEntry(entry.release(), *arc))

docs/doxygen/overviews/debugging.h

@@ -81,7 +81,7 @@ Example of using an assertion macro:
 @code
 void GetTheAnswer(int *p)
 {
-    wxCHECK_RET( p, "pointer can't be NULL in GetTheAnswer()" );
+    wxCHECK_RET( p, "pointer can't be null in GetTheAnswer()" );
 
     *p = 42;
 };
@@ -89,7 +89,7 @@ void GetTheAnswer(int *p)
 
 If the condition is false, i.e. @c p is @NULL, the assertion handler is called
 and, in any case (even when wxDEBUG_LEVEL is 0), the function returns without
-dereferencing the NULL pointer on the next line thus avoiding a crash.
+dereferencing the null pointer on the next line thus avoiding a crash.
 
 The default assertion handler behaviour depends on whether the application
 using wxWidgets was compiled in release build (with @c NDEBUG defined) or debug

docs/doxygen/overviews/helloworld.h

@@ -127,7 +127,7 @@ window. Both have to be bound to the frame with respective calls.
 
 @code
 MyFrame::MyFrame()
-        : wxFrame(NULL, wxID_ANY, "Hello World")
+        : wxFrame(nullptr, wxID_ANY, "Hello World")
 {
     wxMenu *menuFile = new wxMenu;
     menuFile->Append(ID_Hello, "&Hello...\tCtrl-H",
@@ -272,7 +272,7 @@ bool MyApp::OnInit()
 }
 
 MyFrame::MyFrame()
-    : wxFrame(NULL, wxID_ANY, "Hello World")
+    : wxFrame(nullptr, wxID_ANY, "Hello World")
 {
     wxMenu *menuFile = new wxMenu;
     menuFile->Append(ID_Hello, "&Hello...\tCtrl-H",

docs/doxygen/overviews/ipc.h

@@ -200,7 +200,7 @@ connection = (MyConnection *)client->MakeConnection(hostName, server, "IPC TEST"
 if (!connection)
 {
     wxMessageBox("Failed to make connection to server", "Client Demo Error");
-    return NULL;
+    return nullptr;
 }
 
 connection->StartAdvise("Item");

docs/doxygen/overviews/propgrid.h

@@ -270,7 +270,7 @@ A very simple example:
     // Using wxChar* array
     //
     const wxChar* arrayDiet[] =
-    { wxT("Herbivore"), wxT("Carnivore"), wxT("Omnivore"), NULL };
+    { wxT("Herbivore"), wxT("Carnivore"), wxT("Omnivore"), nullptr };
 
     pg->Append( new wxEnumProperty("Diet",
                                    wxPG_LABEL,
@@ -348,7 +348,7 @@ wxFlagsProperty has similar construction:
 @code
 
     const wxChar* flags_prop_labels[] = { wxT("wxICONIZE"),
-        wxT("wxCAPTION"), wxT("wxMINIMIZE_BOX"), wxT("wxMAXIMIZE_BOX"), NULL };
+        wxT("wxCAPTION"), wxT("wxMINIMIZE_BOX"), wxT("wxMAXIMIZE_BOX"), nullptr };
 
     // this value array would be optional if values matched string indexes
     long flags_prop_values[] = { wxICONIZE, wxCAPTION, wxMINIMIZE_BOX,

docs/doxygen/overviews/string.h

@@ -71,7 +71,7 @@ Example:
     // it's a single Unicode code-point encoded as:
     // - a UTF16 surrogate pair under Windows
     // - a UTF8 multiple-bytes sequence under Linux
-    // (without considering the final NULL)
+    // (without considering the final NUL)
 
     wxPrintf("wxString reports a length of %d character(s)", test.length());
         // prints "wxString reports a length of 1 character(s)" on Linux
@@ -88,7 +88,7 @@ Example:
     // they are 3 Unicode code-points encoded as:
     // - 3 UTF16 code units under Windows
     // - 6 UTF8 code units under Linux
-    // (without considering the final NULL)
+    // (without considering the final NUL)
 
     wxPrintf("wxString reports a length of %d character(s)", test2.length());
         // prints "wxString reports a length of 3 character(s)" on Linux
@@ -96,7 +96,7 @@ Example:
 @endcode
 
 To better explain what stated above, consider the second string of the example
-above; it's composed by 3 characters and the final @c NULL:
+above; it's composed by 3 characters and the final @NUL:
 
 @image html overview_wxstring_encoding.png
 
@@ -303,12 +303,12 @@ for (i = s.begin(); i != s.end(); ++i)
 As most programs use character strings, the standard C library provides quite
 a few functions to work with them. Unfortunately, some of them have rather
 counter-intuitive behaviour (like @c strncpy() which doesn't always terminate
-the resulting string with a @NULL) and are in general not very safe (passing
+the resulting string with a @NUL) and are in general not very safe (passing
 @NULL to them will probably lead to program crash). Moreover, some very useful
 functions are not standard at all. This is why in addition to all wxString
 functions, there are also a few global string functions which try to correct
 these problems: wxIsEmpty() verifies whether the string is empty (returning
-@true for @NULL pointers), wxStrlen() also handles @NULL correctly and returns
+@true for @NULL), wxStrlen() also handles @NULL correctly and returns
 0 for them and wxStricmp() is just a platform-independent version of
 case-insensitive string comparison function known either as @c stricmp() or
 @c strcasecmp() on different platforms.

docs/doxygen/overviews/xrc.h

@@ -142,7 +142,7 @@ This is how you would use the above simple dialog in your code.
 void MyClass::ShowDialog()
 {
     wxDialog dlg;
-    if (wxXmlResource::Get()->LoadDialog(&dlg, NULL, "SimpleDialog"))
+    if (wxXmlResource::Get()->LoadDialog(&dlg, nullptr, "SimpleDialog"))
         dlg.ShowModal();
 }
 @endcode
@@ -165,7 +165,7 @@ the XRCCTRL macro to get a pointer to the child. To expand the previous code:
 void MyClass::ShowDialog()
 {
     wxDialog dlg;
-    if (!wxXmlResource::Get()->LoadDialog(&dlg, NULL, "SimpleDialog"))
+    if (!wxXmlResource::Get()->LoadDialog(&dlg, nullptr, "SimpleDialog"))
         return;
 
     wxTextCtrl* pText = XRCCTRL(dlg, "text", wxTextCtrl);
@@ -195,7 +195,7 @@ control to the XRCID macro:
 void MyClass::ShowDialog()
 {
     wxDialog dlg;
-    if (!wxXmlResource::Get()->LoadDialog(&dlg, NULL, "SimpleDialog"))
+    if (!wxXmlResource::Get()->LoadDialog(&dlg, nullptr, "SimpleDialog"))
         return;
 
     XRCCTRL(dlg, "text", wxTextCtrl)->Bind(wxEVT_TEXT,
@@ -367,7 +367,7 @@ protected:
 private:
     void InitWidgetsFromXRC()
     {
-        wxXmlResource::Get()->LoadObject(this, NULL, "TestWnd", "wxFrame");
+        wxXmlResource::Get()->LoadObject(this, nullptr, "TestWnd", "wxFrame");
         A = XRCCTRL(*this, "A", wxTextCtrl);
         B = XRCCTRL(*this, "B", wxButton);
     }

docs/qt/architecture.md

@@ -59,7 +59,7 @@ The approach chosen was to use templates to help inherit QObject's (QWidget), pr
 
 ### Delete later
 
-Both templates also have some safety checks to avoid invalid spurious access to deleted wx objects (using a special pointer to the wx instance stored in the Qt object, that is reset to NULL when the wx counterpart is marked to deletion).
+Both templates also have some safety checks to avoid invalid spurious access to deleted wx objects (using a special pointer to the wx instance stored in the Qt object, that is reset to @NULL when the wx counterpart is marked to deletion).
 
 This is due that in some situations, Qt object could still be referenced in the Qt event queue, so it cannot be removed immediately.
 

include/wx/aboutdlg.h

@@ -161,7 +161,7 @@ private:
 };
 
 // functions to show the about dialog box
-WXDLLIMPEXP_ADV void wxAboutBox(const wxAboutDialogInfo& info, wxWindow* parent = NULL);
+WXDLLIMPEXP_ADV void wxAboutBox(const wxAboutDialogInfo& info, wxWindow* parent = nullptr);
 
 #endif // wxUSE_ABOUTDLG
 

include/wx/accel.h

@@ -48,18 +48,18 @@ class WXDLLIMPEXP_CORE wxAcceleratorEntry
 {
 public:
     wxAcceleratorEntry(int flags = 0, int keyCode = 0, int cmd = 0,
-                       wxMenuItem *item = NULL)
+                       wxMenuItem *item = nullptr)
         : m_flags(flags)
         , m_keyCode(keyCode)
         , m_command(cmd)
         , m_item(item)
         { }
 
-    // create accelerator corresponding to the specified string, return NULL if
+    // create accelerator corresponding to the specified string, return nullptr if
     // string couldn't be parsed or a pointer to be deleted by the caller
     static wxAcceleratorEntry *Create(const wxString& str);
 
-    void Set(int flags, int keyCode, int cmd, wxMenuItem *item = NULL)
+    void Set(int flags, int keyCode, int cmd, wxMenuItem *item = nullptr)
     {
         m_flags = flags;
         m_keyCode = keyCode;
@@ -121,7 +121,7 @@ private:
     int m_keyCode;  // ASCII or virtual keycode
     int m_command;  // Command id to generate
 
-    // the menu item this entry corresponds to, may be NULL
+    // the menu item this entry corresponds to, may be null
     wxMenuItem *m_item;
 
     // for compatibility with old code, use accessors now!

include/wx/access.h

@@ -263,13 +263,13 @@ public:
          { return wxACC_NOT_IMPLEMENTED; }
 
         // Gets the specified child (starting from 1).
-        // If *child is NULL and return value is wxACC_OK,
+        // If *child is null and return value is wxACC_OK,
         // this means that the child is a simple element and
         // not an accessible object.
     virtual wxAccStatus GetChild(int WXUNUSED(childId), wxAccessible** WXUNUSED(child))
          { return wxACC_NOT_IMPLEMENTED; }
 
-        // Gets the parent, or NULL.
+        // Gets the parent, or nullptr.
     virtual wxAccStatus GetParent(wxAccessible** WXUNUSED(parent))
          { return wxACC_NOT_IMPLEMENTED; }
 
@@ -320,7 +320,7 @@ public:
          { return wxACC_NOT_IMPLEMENTED; }
 
         // Gets the window with the keyboard focus.
-        // If childId is 0 and child is NULL, no object in
+        // If childId is 0 and child is null, no object in
         // this subhierarchy has the focus.
         // If this object has the focus, child should be 'this'.
     virtual wxAccStatus GetFocus(int* WXUNUSED(childId), wxAccessible** WXUNUSED(child))

include/wx/addremovectrl.h

@@ -96,7 +96,7 @@ private:
     // Common part of all ctors.
     void Init()
     {
-        m_impl = NULL;
+        m_impl = nullptr;
     }
 
     class wxAddRemoveImpl* m_impl;

include/wx/affinematrix2dbase.h

@@ -92,7 +92,7 @@ public:
 
     void TransformPoint(wxDouble* x, wxDouble* y) const
     {
-        wxCHECK_RET( x && y, "Can't be NULL" );
+        wxCHECK_RET( x && y, "Can't be null" );
 
         const wxPoint2DDouble dst = DoTransformPoint(wxPoint2DDouble(*x, *y));
         *x = dst.m_x;
@@ -107,7 +107,7 @@ public:
 
     void TransformDistance(wxDouble* dx, wxDouble* dy) const
     {
-        wxCHECK_RET( dx && dy, "Can't be NULL" );
+        wxCHECK_RET( dx && dy, "Can't be null" );
 
         const wxPoint2DDouble
             dst = DoTransformDistance(wxPoint2DDouble(*dx, *dy));

include/wx/any.h

@@ -44,7 +44,7 @@ union wxAnyValueBuffer
 
     wxAnyValueBuffer()
     {
-        m_ptr = NULL;
+        m_ptr = nullptr;
     }
 };
 
@@ -324,7 +324,7 @@ public:
 #if wxUSE_EXTENDED_RTTI
     virtual const wxTypeInfo* GetTypeInfo() const
     {
-        return wxGetTypeInfo((T*)NULL);
+        return wxGetTypeInfo((T*)nullptr);
     }
 #endif
 };
@@ -389,7 +389,7 @@ public: \
 _WX_ANY_DEFINE_SUB_TYPE(T, CLSTYPE)\
     virtual const wxTypeInfo* GetTypeInfo() const  \
     { \
-        return wxGetTypeInfo((T*)NULL); \
+        return wxGetTypeInfo((T*)nullptr); \
     } \
 };
 #else
@@ -673,7 +673,7 @@ public:
 
 /*
     Let's define a discrete Null value so we don't have to really
-    ever check if wxAny.m_type pointer is NULL or not. This is an
+    ever check if wxAny.m_type pointer is null or not. This is an
     optimization, mostly. Implementation of this value type is
     "hidden" in the source file.
 */
@@ -965,7 +965,7 @@ public:
                  const char* and const wchar_t*) has been assigned to wxAny.
     */
     template <typename T>
-    T As(T* = NULL) const
+    T As(T* = nullptr) const
     {
         return wxPrivate::wxAnyAsImpl<T>::DoAs(*this);
     }
@@ -1124,7 +1124,7 @@ struct wxAnyAsImpl<wxString>
 // This macro shouldn't be used any longer for the same reasons as
 // wxANY_VALUE_TYPE_CHECK_TYPE(), just call As() directly.
 #define wxANY_AS(any, T) \
-    (any).As(static_cast<T*>(NULL))
+    (any).As(static_cast<T*>(nullptr))
 
 
 template<typename T>

include/wx/anystr.h

@@ -22,7 +22,7 @@
 // ----------------------------------------------------------------------------
 
 // This is a helper class convertible to either narrow or wide string pointer.
-// It is similar to wxCStrData but, unlike it, can be NULL which is required to
+// It is similar to wxCStrData but, unlike it, can be null which is required to
 // represent the return value of wxDateTime::ParseXXX() methods for example.
 //
 // NB: this class is fully inline and so doesn't need to be DLL-exported
@@ -30,12 +30,12 @@ class wxAnyStrPtr
 {
 public:
     // ctors: this class must be created from the associated string or using
-    // its default ctor for an invalid NULL-like object; notice that it is
+    // its default ctor for an invalid nullptr-like object; notice that it is
     // immutable after creation.
 
     // ctor for invalid pointer
     wxAnyStrPtr()
-        : m_str(NULL)
+        : m_str(nullptr)
     {
     }
 
@@ -58,7 +58,7 @@ public:
     // e.g. "if ( FuncReturningAnyStrPtr() && ... )" (unfortunately using
     // unspecified_bool_type here wouldn't help with ambiguity between all the
     // different conversions to pointers)
-    operator bool() const { return m_str != NULL; }
+    operator bool() const { return m_str != nullptr; }
 
     // at least VC7 also needs this one or it complains about ambiguity
     // for !anystr expressions
@@ -71,7 +71,7 @@ public:
     operator const char *() const
     {
         if ( !m_str )
-            return NULL;
+            return nullptr;
 
         // check if the string is convertible to char at all
         //
@@ -100,7 +100,7 @@ public:
     operator const wchar_t *() const
     {
         if ( !m_str )
-            return NULL;
+            return nullptr;
 
         // no complications with wide strings (as long as we discount
         // surrogates as we do for now)
@@ -112,8 +112,8 @@ public:
     }
 
     // Because the objects of this class are only used as return type for
-    // functions which can return NULL we can skip providing dereferencing
+    // functions which can return nullptr we can skip providing dereferencing
-    // operators: the code using this class must test it for NULL first and if
+    // operators: the code using this class must test it for null first and if
     // it does anything else with it has to assign it to either char* or
     // wchar_t* itself, before dereferencing.
     //
@@ -130,7 +130,7 @@ public:
 
 private:
     // the original string and the position in it we correspond to, if the
-    // string is NULL this object is NULL pointer-like
+    // string is null this object is null pointer-like
     const wxString * const m_str;
     const wxString::const_iterator m_iter;
 

include/wx/app.h

@@ -226,14 +226,14 @@ public:
     // wxTheApp->GetTraits() during startup or termination when the global
     // application object itself may be unavailable
     //
-    // of course, it still returns NULL in this case and the caller must check
+    // of course, it still returns nullptr in this case and the caller must check
     // for it
     static wxAppTraits *GetTraitsIfExists();
 
     // Return some valid traits object.
     //
     // This method checks if we have wxTheApp and returns its traits if it does
-    // exist and the traits are non-NULL, similarly to GetTraitsIfExists(), but
+    // exist and the traits are non-null, similarly to GetTraitsIfExists(), but
     // falls back to wxConsoleAppTraits to ensure that it always returns
     // something valid.
     static wxAppTraits& GetValidTraits();
@@ -241,8 +241,8 @@ public:
     // returns the main event loop instance, i.e. the event loop which is started
     // by OnRun() and which dispatches all events sent from the native toolkit
     // to the application (except when new event loops are temporarily set-up).
-    // The returned value maybe NULL. Put initialization code which needs a
+    // The returned value maybe null. Put initialization code which needs a
-    // non-NULL main event loop into OnEventLoopEnter().
+    // non-null main event loop into OnEventLoopEnter().
     wxEventLoopBase* GetMainLoop() const
         { return m_mainLoop; }
 
@@ -495,7 +495,7 @@ protected:
     // the one and only global application object
     static wxAppConsole *ms_appInstance;
 
-    // create main loop from AppTraits or return NULL if
+    // create main loop from AppTraits or return nullptr if
     // there is no main loop implementation
     wxEventLoopBase *CreateMainLoop();
 
@@ -506,11 +506,11 @@ protected:
              m_appDisplayName,    // app display name ("My Application")
              m_className;         // class name
 
-    // the class defining the application behaviour, NULL initially and created
+    // the class defining the application behaviour, nullptr initially and created
     // by GetTraits() when first needed
     wxAppTraits *m_traits;
 
-    // the main event loop of the application (may be NULL if the loop hasn't
+    // the main event loop of the application (may be null if the loop hasn't
     // been started yet or has already terminated)
     wxEventLoopBase *m_mainLoop;
 
@@ -622,11 +622,11 @@ public:
 
         // return the "main" top level window (if it hadn't been set previously
         // with SetTopWindow(), will return just some top level window and, if
-        // there are none, will return NULL)
+        // there are none, will return nullptr)
     virtual wxWindow *GetTopWindow() const;
 
         // convenient helper which is safe to use even if there is no wxApp at
-        // all, it will just return NULL in this case
+        // all, it will just return nullptr in this case
     static wxWindow *GetMainTopWindow();
 
         // control the exit behaviour: by default, the program will exit the
@@ -697,7 +697,7 @@ public:
     {
         return ms_appInstance && ms_appInstance->IsGUI()
                 ? static_cast<wxAppBase*>(ms_appInstance)
-                : NULL;
+                : nullptr;
     }
 
 protected:
@@ -709,7 +709,7 @@ protected:
     void DeleteAllTLWs();
 
 
-    // the main top level window (may be NULL)
+    // the main top level window (may be null)
     wxWindow *m_topWindow;
 
     // if Yes, exit the main loop when the last top level window is deleted, if

include/wx/appprogress.h

@@ -37,7 +37,7 @@ private:
     class wxAppProgressIndicator : public wxAppProgressIndicatorBase
     {
     public:
-        wxAppProgressIndicator(wxWindow* WXUNUSED(parent) = NULL,
+        wxAppProgressIndicator(wxWindow* WXUNUSED(parent) = nullptr,
                                int WXUNUSED(maxValue) = 100)
         {
         }

include/wx/apptrait.h

@@ -66,8 +66,8 @@ public:
 #endif // wxUSE_FONTMAP
 
     // get the renderer to use for drawing the generic controls (return value
-    // may be NULL in which case the default renderer for the current platform
+    // may be null in which case the default renderer for the current platform
-    // is used); this is used in GUI only and always returns NULL in console
+    // is used); this is used in GUI only and always returns nullptr in console
     //
     // NB: returned pointer will be deleted by the caller
     virtual wxRendererNative *CreateRenderer() = 0;
@@ -139,9 +139,9 @@ public:
     // runtime (not compile-time) version.
     // returns wxPORT_BASE for console applications and one of the remaining
     // wxPORT_* values for GUI applications.
-    virtual wxPortId GetToolkitVersion(int *majVer = NULL,
+    virtual wxPortId GetToolkitVersion(int *majVer = nullptr,
-                                       int *minVer = NULL,
+                                       int *minVer = nullptr,
-                                       int *microVer = NULL) const = 0;
+                                       int *microVer = nullptr) const = 0;
 
     // return true if the port is using wxUniversal for the GUI, false if not
     virtual bool IsUsingUniversalWidgets() const = 0;
@@ -206,7 +206,7 @@ class WXDLLIMPEXP_BASE wxConsoleAppTraitsBase : public wxAppTraits
 {
 public:
 #if !wxUSE_CONSOLE_EVENTLOOP
-    virtual wxEventLoopBase *CreateEventLoop() override { return NULL; }
+    virtual wxEventLoopBase *CreateEventLoop() override { return nullptr; }
 #endif // !wxUSE_CONSOLE_EVENTLOOP
 
 #if wxUSE_LOG
@@ -224,9 +224,9 @@ public:
                                 const wxString& title) override;
 
     // the GetToolkitVersion for console application is always the same
-    wxPortId GetToolkitVersion(int *verMaj = NULL,
+    wxPortId GetToolkitVersion(int *verMaj = nullptr,
-                               int *verMin = NULL,
+                               int *verMin = nullptr,
-                               int *verMicro = NULL) const override
+                               int *verMicro = nullptr) const override
     {
         // no toolkits (wxBase is for console applications without GUI support)
         // NB: zero means "no toolkit", -1 means "not initialized yet"

include/wx/archive.h

@@ -58,11 +58,11 @@ public:
     wxArchiveEntry *Clone() const { return DoClone(); }
 
     void SetNotifier(wxArchiveNotifier& notifier);
-    virtual void UnsetNotifier() { m_notifier = NULL; }
+    virtual void UnsetNotifier() { m_notifier = nullptr; }
 
 protected:
-    wxArchiveEntry() : m_notifier(NULL) { }
+    wxArchiveEntry() : m_notifier(nullptr) { }
-    wxArchiveEntry(const wxArchiveEntry& e) : wxObject(e), m_notifier(NULL) { }
+    wxArchiveEntry(const wxArchiveEntry& e) : wxObject(e), m_notifier(nullptr) { }
 
     virtual void SetOffset(wxFileOffset offset) = 0;
     virtual wxArchiveEntry* DoClone() const = 0;
@@ -85,7 +85,7 @@ private:
 // the wxArchiveInputStream then returns the entry's data. Eof() becomes true
 // after an attempt has been made to read past the end of the entry's data.
 //
-// When there are no more entries, GetNextEntry() returns NULL and sets Eof().
+// When there are no more entries, GetNextEntry() returns nullptr and sets Eof().
 
 class WXDLLIMPEXP_BASE wxArchiveInputStream : public wxFilterInputStream
 {
@@ -191,11 +191,11 @@ public:
     typedef T* pointer;
     typedef T& reference;
 
-    wxArchiveIterator() : m_rep(NULL) { }
+    wxArchiveIterator() : m_rep(nullptr) { }
 
     wxArchiveIterator(Arc& arc) {
         typename Arc::entry_type* entry = arc.GetNextEntry();
-        m_rep = entry ? new Rep(arc, entry) : NULL;
+        m_rep = entry ? new Rep(arc, entry) : nullptr;
     }
 
     wxArchiveIterator(const wxArchiveIterator& it) : m_rep(it.m_rep) {
@@ -270,7 +270,7 @@ private:
             typename Arc::entry_type* entry = m_arc.GetNextEntry();
             if (!entry) {
                 UnRef();
-                return NULL;
+                return nullptr;
             }
             if (m_ref > 1) {
                 m_ref--;
@@ -285,7 +285,7 @@ private:
         const T& GetValue() {
             if (m_entry) {
                 _wxSetArchiveIteratorValue(m_value, m_entry, m_entry);
-                m_entry = NULL;
+                m_entry = nullptr;
             }
             return m_value;
         }
@@ -361,7 +361,7 @@ protected:
     virtual wxArchiveInputStream  *DoNewStream(wxInputStream *stream) const = 0;
     virtual wxArchiveOutputStream *DoNewStream(wxOutputStream *stream) const = 0;
 
-    wxArchiveClassFactory() : m_pConv(NULL), m_next(this) { }
+    wxArchiveClassFactory() : m_pConv(nullptr), m_next(this) { }
     wxArchiveClassFactory& operator=(const wxArchiveClassFactory& WXUNUSED(f))
         { return *this; }
 

include/wx/arrstr.h

@@ -287,7 +287,7 @@ public:
     friend difference_type operator -(const itor& i1, const itor& i2);
   public:
     pointer m_ptr;
-    reverse_iterator() : m_ptr(NULL) { }
+    reverse_iterator() : m_ptr(nullptr) { }
     explicit reverse_iterator(pointer ptr) : m_ptr(ptr) { }
     reverse_iterator(const itor& it) : m_ptr(it.m_ptr) { }
     reference operator*() const { return *m_ptr; }
@@ -313,7 +313,7 @@ public:
     friend difference_type operator -(const itor& i1, const itor& i2);
   public:
     pointer m_ptr;
-    const_reverse_iterator() : m_ptr(NULL) { }
+    const_reverse_iterator() : m_ptr(nullptr) { }
     explicit const_reverse_iterator(pointer ptr) : m_ptr(ptr) { }
     const_reverse_iterator(const itor& it) : m_ptr(it.m_ptr) { }
     const_reverse_iterator(const reverse_iterator& it) : m_ptr(it.m_ptr) { }
@@ -395,7 +395,7 @@ protected:
 private:
   // Allocate the new buffer big enough to hold m_nCount + nIncrement items and
   // return the pointer to the old buffer, which must be deleted by the caller
-  // (if the old buffer is big enough, just return NULL).
+  // (if the old buffer is big enough, just return nullptr).
   wxString *Grow(size_t nIncrement);
 
   // Binary search in the sorted array: return the index of the string if it's
@@ -432,7 +432,7 @@ class WXDLLIMPEXP_BASE wxCArrayString
 {
 public:
     wxCArrayString( const wxArrayString& array )
-        : m_array( array ), m_strings( NULL )
+        : m_array( array ), m_strings( nullptr )
     { }
     ~wxCArrayString() { delete[] m_strings; }
 
@@ -450,7 +450,7 @@ public:
     wxString* Release()
     {
         wxString *r = GetStrings();
-        m_strings = NULL;
+        m_strings = nullptr;
         return r;
     }
 
@@ -513,7 +513,7 @@ public:
     wxArrayStringsAdapter(const std::vector<wxString>& strings)
         : m_type(wxSTRING_POINTER), m_size(strings.size())
     {
-        m_data.ptr = m_size == 0 ? NULL : &strings[0];
+        m_data.ptr = m_size == 0 ? nullptr : &strings[0];
     }
 #endif // wxUSE_STD_CONTAINERS_COMPATIBLY
 

include/wx/artprov.h

@@ -195,12 +195,12 @@ public:
     // Gets native size for given 'client' or wxDefaultSize if it doesn't
     // have native equivalent. The first version returns the size in logical
     // pixels while the second one returns it in DIPs.
-    static wxSize GetNativeSizeHint(const wxArtClient& client, wxWindow* win = NULL);
+    static wxSize GetNativeSizeHint(const wxArtClient& client, wxWindow* win = nullptr);
     static wxSize GetNativeDIPSizeHint(const wxArtClient& client);
 
     // Get the size hint of an icon from a specific wxArtClient from the
     // topmost (i.e. first used) provider.
-    static wxSize GetSizeHint(const wxArtClient& client, wxWindow* win = NULL);
+    static wxSize GetSizeHint(const wxArtClient& client, wxWindow* win = nullptr);
     static wxSize GetDIPSizeHint(const wxArtClient& client);
 
 #if WXWIN_COMPATIBILITY_3_0

include/wx/aui/auibar.h

@@ -110,8 +110,8 @@ public:
 
     wxAuiToolBarItem()
     {
-        m_window = NULL;
+        m_window = nullptr;
-        m_sizerItem = NULL;
+        m_sizerItem = nullptr;
         m_spacerPixels = 0;
         m_toolId = 0;
         m_kind = wxITEM_NORMAL;
@@ -507,7 +507,7 @@ public:
                  const wxBitmapBundle& bitmap,
                  const wxBitmapBundle& disabledBitmap,
                  bool toggle = false,
-                 wxObject* clientData = NULL,
+                 wxObject* clientData = nullptr,
                  const wxString& shortHelpString = wxEmptyString,
                  const wxString& longHelpString = wxEmptyString)
     {

include/wx/aui/auibook.h

@@ -68,7 +68,7 @@ public:
                        int winId = 0)
           : wxBookCtrlEvent(commandType, winId)
     {
-        m_dragSource = NULL;
+        m_dragSource = nullptr;
     }
     wxEvent *Clone() const override { return new wxAuiNotebookEvent(*this); }
 
@@ -151,7 +151,7 @@ public:
     void SetColour(const wxColour& colour);
     void SetActiveColour(const wxColour& colour);
     void DoShowHide();
-    void SetRect(const wxRect& rect, wxWindow* wnd = NULL);
+    void SetRect(const wxRect& rect, wxWindow* wnd = nullptr);
 
     void RemoveButton(int id);
     void AddButton(int id,
@@ -344,7 +344,7 @@ public:
     //wxBookCtrlBase functions
 
     virtual void SetPageSize (const wxSize &size) override;
-    virtual int  HitTest (const wxPoint &pt, long *flags=NULL) const override;
+    virtual int  HitTest (const wxPoint &pt, long *flags=nullptr) const override;
 
     virtual int GetPageImage(size_t n) const override;
     virtual bool SetPageImage(size_t n, int imageId) override;
@@ -383,7 +383,7 @@ protected:
     virtual wxSize CalculateNewSplitSize();
 
     // remove the page and return a pointer to it
-    virtual wxWindow *DoRemovePage(size_t WXUNUSED(page)) override { return NULL; }
+    virtual wxWindow *DoRemovePage(size_t WXUNUSED(page)) override { return nullptr; }
 
     //A general selection function
     virtual int DoModifySelection(size_t n, bool events);
@@ -415,7 +415,7 @@ protected:
     void OnNavigationKeyNotebook(wxNavigationKeyEvent& event);
     void OnSysColourChanged(wxSysColourChangedEvent& event);
 
-    // set selection to the given window (which must be non-NULL and be one of
+    // set selection to the given window (which must be non-null and be one of
     // our pages, otherwise an assert is raised)
     void SetSelectionToWindow(wxWindow *win);
     void SetSelectionToPage(const wxAuiNotebookPage& page)

include/wx/aui/framemanager.h

@@ -152,8 +152,8 @@ public:
         , floating_pos(wxDefaultPosition)
         , floating_size(wxDefaultSize)
     {
-        window = NULL;
+        window = nullptr;
-        frame = NULL;
+        frame = nullptr;
         state = 0;
         dock_direction = wxAUI_DOCK_LEFT;
         dock_layer = 0;
@@ -180,7 +180,7 @@ public:
         *this = source;
     }
 
-    bool IsOk() const { return window != NULL; }
+    bool IsOk() const { return window != nullptr; }
     bool IsFixed() const { return !HasFlag(optionResizable); }
     bool IsResizable() const { return HasFlag(optionResizable); }
     bool IsShown() const { return !HasFlag(optionHidden); }
@@ -405,7 +405,7 @@ class WXDLLIMPEXP_AUI wxAuiManager : public wxEvtHandler
 
 public:
 
-    wxAuiManager(wxWindow* managedWnd = NULL,
+    wxAuiManager(wxWindow* managedWnd = nullptr,
                    unsigned int flags = wxAUI_MGR_DEFAULT);
     virtual ~wxAuiManager();
     void UnInit();
@@ -533,7 +533,7 @@ protected:
     void OnFloatingPaneClosed(wxWindow* window, wxCloseEvent& evt);
     void OnFloatingPaneResized(wxWindow* window, const wxRect& rect);
     void Render(wxDC* dc);
-    void Repaint(wxDC* dc = NULL);
+    void Repaint(wxDC* dc = nullptr);
     void ProcessMgrEvent(wxAuiManagerEvent& event);
     void UpdateButtonOnScreen(wxAuiDockUIPart* buttonUiPart,
                               const wxMouseEvent& event);
@@ -596,7 +596,7 @@ protected:
     wxPoint m_actionStart;      // position where the action click started
     wxPoint m_actionOffset;     // offset from upper left of the item clicked
     wxAuiDockUIPart* m_actionPart; // ptr to the part the action happened to
-    wxWindow* m_actionWindow;   // action frame or window (NULL if none)
+    wxWindow* m_actionWindow;   // action frame or window (nullptr if none)
     wxRect m_actionHintRect;    // hint rectangle for the action
     wxRect m_lastRect;
     wxAuiDockUIPart* m_hoverButton;// button uipart being hovered over
@@ -630,12 +630,12 @@ class WXDLLIMPEXP_AUI wxAuiManagerEvent : public wxEvent
 public:
     wxAuiManagerEvent(wxEventType type=wxEVT_NULL) : wxEvent(0, type)
     {
-        manager = NULL;
+        manager = nullptr;
-        pane = NULL;
+        pane = nullptr;
         button = 0;
         veto_flag = false;
         canveto_flag = true;
-        dc = NULL;
+        dc = nullptr;
     }
     wxEvent *Clone() const override { return new wxAuiManagerEvent(*this); }
 

include/wx/aui/tabart.h

@@ -48,7 +48,7 @@ public:
 
     virtual void SetSizingInfo(const wxSize& tabCtrlSize,
                                size_t tabCount,
-                               wxWindow* wnd = NULL) = 0;
+                               wxWindow* wnd = nullptr) = 0;
 
     virtual void SetNormalFont(const wxFont& font) = 0;
     virtual void SetSelectedFont(const wxFont& font) = 0;
@@ -128,7 +128,7 @@ public:
     void SetFlags(unsigned int flags) override;
     void SetSizingInfo(const wxSize& tabCtrlSize,
                        size_t tabCount,
-                       wxWindow* wnd = NULL) override;
+                       wxWindow* wnd = nullptr) override;
 
     void SetNormalFont(const wxFont& font) override;
     void SetSelectedFont(const wxFont& font) override;
@@ -231,7 +231,7 @@ public:
 
     void SetSizingInfo(const wxSize& tabCtrlSize,
                        size_t tabCount,
-                       wxWindow* wnd = NULL) override;
+                       wxWindow* wnd = nullptr) override;
 
     void SetNormalFont(const wxFont& font) override;
     void SetSelectedFont(const wxFont& font) override;

include/wx/base64.h

@@ -29,7 +29,7 @@ inline size_t wxBase64EncodedSize(size_t len) { return 4*((len+2)/3); }
 //
 // returns the length of the encoded data or wxCONV_FAILED if the buffer is not
 // large enough; to determine the needed size you can either allocate a buffer
-// of wxBase64EncodedSize(srcLen) size or call the function with NULL buffer in
+// of wxBase64EncodedSize(srcLen) size or call the function with null buffer in
 // which case the required size will be returned
 WXDLLIMPEXP_BASE size_t
 wxBase64Encode(char *dst, size_t dstLen, const void *src, size_t srcLen);
@@ -83,18 +83,18 @@ inline size_t wxBase64DecodedSize(size_t srcLen) { return 3*srcLen/4; }
 // returns the length of the decoded data or wxCONV_FAILED if an error occurs
 // such as the buffer is too small or the encoded string is invalid; in the
 // latter case the posErr is filled with the position where the decoding
-// stopped if it is not NULL
+// stopped if it is not null
 WXDLLIMPEXP_BASE size_t
 wxBase64Decode(void *dst, size_t dstLen,
                const char *src, size_t srcLen = wxNO_LEN,
                wxBase64DecodeMode mode = wxBase64DecodeMode_Strict,
-               size_t *posErr = NULL);
+               size_t *posErr = nullptr);
 
 inline size_t
 wxBase64Decode(void *dst, size_t dstLen,
                const wxString& src,
                wxBase64DecodeMode mode = wxBase64DecodeMode_Strict,
-               size_t *posErr = NULL)
+               size_t *posErr = nullptr)
 {
     // don't use str.length() here as the ASCII buffer is shorter than it for
     // strings with embedded NULs
@@ -106,12 +106,12 @@ wxBase64Decode(void *dst, size_t dstLen,
 WXDLLIMPEXP_BASE wxMemoryBuffer
 wxBase64Decode(const char *src, size_t srcLen = wxNO_LEN,
                wxBase64DecodeMode mode = wxBase64DecodeMode_Strict,
-               size_t *posErr = NULL);
+               size_t *posErr = nullptr);
 
 inline wxMemoryBuffer
 wxBase64Decode(const wxString& src,
                wxBase64DecodeMode mode = wxBase64DecodeMode_Strict,
-               size_t *posErr = NULL)
+               size_t *posErr = nullptr)
 {
     // don't use str.length() here as the ASCII buffer is shorter than it for
     // strings with embedded NULs

include/wx/bitmap.h

@@ -135,7 +135,7 @@ public:
         { return false; }
 
     virtual bool SaveFile(const wxBitmap *WXUNUSED(bitmap), const wxString& WXUNUSED(name),
-                           wxBitmapType WXUNUSED(type), const wxPalette *WXUNUSED(palette) = NULL) const
+                           wxBitmapType WXUNUSED(type), const wxPalette *WXUNUSED(palette) = nullptr) const
         { return false; }
 
     void SetName(const wxString& name)      { m_name = name; }
@@ -233,7 +233,7 @@ public:
     virtual wxBitmap GetSubBitmap(const wxRect& rect) const = 0;
 
     virtual bool SaveFile(const wxString &name, wxBitmapType type,
-                          const wxPalette *palette = NULL) const = 0;
+                          const wxPalette *palette = nullptr) const = 0;
     virtual bool LoadFile(const wxString &name, wxBitmapType type) = 0;
 
     /*

include/wx/bmpbndl.h

@@ -112,7 +112,7 @@ public:
     static wxBitmapBundle FromImpl(wxBitmapBundleImpl* impl);
 
     // Check if bitmap bundle is non-empty.
-    bool IsOk() const { return m_impl.get() != NULL; }
+    bool IsOk() const { return m_impl.get() != nullptr; }
 
     // Clear the bundle contents, IsOk() will return false after doing this.
     void Clear();

include/wx/bookctrl.h

@@ -94,11 +94,11 @@ public:
     // get the panel which represents the given page
     virtual wxWindow *GetPage(size_t n) const { return m_pages.at(n); }
 
-    // get the current page or NULL if none
+    // get the current page or nullptr if none
     wxWindow *GetCurrentPage() const
     {
         const int n = GetSelection();
-        return n == wxNOT_FOUND ? NULL : GetPage(n);
+        return n == wxNOT_FOUND ? nullptr : GetPage(n);
     }
 
     // get the currently selected page or wxNOT_FOUND if none
@@ -162,7 +162,7 @@ public:
     virtual bool RemovePage(size_t n)
     {
         DoInvalidateBestSize();
-        return DoRemovePage(n) != NULL;
+        return DoRemovePage(n) != nullptr;
     }
 
     // remove all pages and delete them
@@ -217,7 +217,7 @@ public:
 
     // hit test: returns which page is hit and, optionally, where (icon, label)
     virtual int HitTest(const wxPoint& WXUNUSED(pt),
-                        long * WXUNUSED(flags) = NULL) const
+                        long * WXUNUSED(flags) = nullptr) const
     {
         return wxNOT_FOUND;
     }
@@ -279,7 +279,7 @@ protected:
 
     // create a new "page changing" event
     virtual wxBookCtrlEvent* CreatePageChangingEvent() const
-        { wxFAIL_MSG(wxT("Override this function!")); return NULL; }
+        { wxFAIL_MSG(wxT("Override this function!")); return nullptr; }
 
     // modify the event created by CreatePageChangingEvent() to "page changed"
     // event, usually by just calling SetEventType() on it
@@ -292,15 +292,15 @@ protected:
     virtual void DoShowPage(wxWindow* page, bool show) { page->Show(show); }
 
 
-    // Should we accept NULL page pointers in Add/InsertPage()?
+    // Should we accept null page pointers in Add/InsertPage()?
     //
-    // Default is no but derived classes may override it if they can treat NULL
+    // Default is no but derived classes may override it if they can treat null
     // pages in some sensible way (e.g. wxTreebook overrides this to allow
     // having nodes without any associated page)
     virtual bool AllowNullPage() const { return false; }
 
     // For classes that allow null pages, we also need a way to find the
-    // closest non-NULL page corresponding to the given index, e.g. the first
+    // closest non-null page corresponding to the given index, e.g. the first
     // leaf item in wxTreebook tree and this method must be overridden to
     // return it if AllowNullPage() is overridden. Note that it can still
     // return null if there are no valid pages after this one.
@@ -349,7 +349,7 @@ protected:
     // event handlers
     void OnSize(wxSizeEvent& event);
 
-    // controller buddy if available, NULL otherwise (usually for native book controls like wxNotebook)
+    // controller buddy if available, nullptr otherwise (usually for native book controls like wxNotebook)
     wxWindow *m_bookctrl;
 
     // Whether to shrink to fit current page

include/wx/buffer.h

@@ -133,7 +133,7 @@ public:
     CharType *release() const
     {
         if ( m_data == GetNullData() )
-            return NULL;
+            return nullptr;
 
         wxASSERT_MSG( m_data->m_owned, wxT("can't release non-owned buffer") );
         wxASSERT_MSG( m_data->m_ref == 1, wxT("can't release shared buffer") );
@@ -141,7 +141,7 @@ public:
         CharType * const p = m_data->Get();
 
         wxScopedCharTypeBuffer *self = const_cast<wxScopedCharTypeBuffer*>(this);
-        self->m_data->Set(NULL, 0);
+        self->m_data->Set(nullptr, 0);
         self->DecRef();
 
         return p;
@@ -176,7 +176,7 @@ protected:
         }
     };
 
-    // placeholder for NULL string, to simplify this code
+    // placeholder for null string, to simplify this code
     static Data *GetNullData()
     {
         return static_cast<Data *>(wxPrivate::GetUntypedNullData());
@@ -252,7 +252,7 @@ protected:
 public:
     typedef T CharType;
 
-    wxCharTypeBuffer(const CharType *str = NULL, size_t len = wxNO_LEN)
+    wxCharTypeBuffer(const CharType *str = nullptr, size_t len = wxNO_LEN)
     {
         if ( str )
         {
@@ -365,7 +365,7 @@ public:
     wxCharBuffer(const wxScopedCharTypeBufferBase& buf)
         : wxCharTypeBufferBase(buf) {}
 
-    wxCharBuffer(const CharType *str = NULL) : wxCharTypeBufferBase(str) {}
+    wxCharBuffer(const CharType *str = nullptr) : wxCharTypeBufferBase(str) {}
     wxCharBuffer(size_t len) : wxCharTypeBufferBase(len) {}
 
     wxCharBuffer(const wxCStrData& cstr);
@@ -382,7 +382,7 @@ public:
     wxWCharBuffer(const wxScopedCharTypeBufferBase& buf)
         : wxCharTypeBufferBase(buf) {}
 
-    wxWCharBuffer(const CharType *str = NULL) : wxCharTypeBufferBase(str) {}
+    wxWCharBuffer(const CharType *str = nullptr) : wxCharTypeBufferBase(str) {}
     wxWCharBuffer(size_t len) : wxCharTypeBufferBase(len) {}
 
     wxWCharBuffer(const wxCStrData& cstr);
@@ -401,7 +401,7 @@ public:
     //             always return a buffer
     //             + we should derive this class from wxScopedCharTypeBuffer
     //               then
-    wxWritableCharTypeBuffer(const CharType *str = NULL)
+    wxWritableCharTypeBuffer(const CharType *str = nullptr)
         : wxCharTypeBuffer<T>(str) {}
 
     operator CharType*() { return this->data(); }
@@ -448,7 +448,7 @@ public:
     // everything is private as it can only be used by wxMemoryBuffer
 private:
     wxMemoryBufferData(size_t size = wxMemoryBufferData::DefBufSize)
-        : m_data(size ? malloc(size) : NULL), m_size(size), m_len(0), m_ref(0)
+        : m_data(size ? malloc(size) : nullptr), m_size(size), m_len(0), m_ref(0)
     {
     }
     ~wxMemoryBufferData() { free(m_data); }
@@ -483,13 +483,13 @@ private:
 
     void *release()
     {
-        if ( m_data == NULL )
+        if ( m_data == nullptr )
-            return NULL;
+            return nullptr;
 
         wxASSERT_MSG( m_ref == 1, "can't release shared buffer" );
 
         void *p = m_data;
-        m_data = NULL;
+        m_data = nullptr;
         m_len =
         m_size = 0;
 

include/wx/busyinfo.h

@@ -31,7 +31,7 @@ class wxBusyInfoFlags
 public:
     wxBusyInfoFlags()
     {
-        m_parent = NULL;
+        m_parent = nullptr;
         m_alpha = wxALPHA_OPAQUE;
     }
 

include/wx/button.h

@@ -36,12 +36,12 @@ public:
 
     // make this button the default button in its top level window
     //
-    // returns the old default item (possibly NULL)
+    // returns the old default item (possibly null)
     virtual wxWindow *SetDefault();
 
     // returns the default button size for this platform, and optionally for a
     // specific window when the platform supports per-monitor DPI
-    static wxSize GetDefaultSize(wxWindow* win = NULL);
+    static wxSize GetDefaultSize(wxWindow* win = nullptr);
 
 protected:
     wxDECLARE_NO_COPY_CLASS(wxButtonBase);

include/wx/calctrl.h

@@ -204,7 +204,7 @@ public:
     }
 
     // retrieves the limits currently in use (wxDefaultDateTime if none) in the
-    // provided pointers (which may be NULL) and returns true if there are any
+    // provided pointers (which may be null) and returns true if there are any
     // limits or false if none
     virtual bool
     GetDateRange(wxDateTime *lowerdate, wxDateTime *upperdate) const
@@ -223,8 +223,8 @@ public:
     // notice that this is not implemented in all versions
     virtual wxCalendarHitTestResult
     HitTest(const wxPoint& WXUNUSED(pos),
-            wxDateTime* WXUNUSED(date) = NULL,
+            wxDateTime* WXUNUSED(date) = nullptr,
-            wxDateTime::WeekDay* WXUNUSED(wd) = NULL)
+            wxDateTime::WeekDay* WXUNUSED(wd) = nullptr)
     {
         return wxCAL_HITTEST_NOWHERE;
     }
@@ -253,7 +253,7 @@ public:
     virtual void Mark(size_t day, bool mark) = 0;
 
     virtual wxCalendarDateAttr *GetAttr(size_t WXUNUSED(day)) const
-        { return NULL; }
+        { return nullptr; }
     virtual void SetAttr(size_t WXUNUSED(day), wxCalendarDateAttr *attr)
         { delete attr; }
     virtual void ResetAttr(size_t WXUNUSED(day)) { }

include/wx/caret.h

@@ -179,7 +179,7 @@ protected:
 private:
     void Init()
     {
-        m_window = NULL;
+        m_window = nullptr;
         m_x = m_y = 0;
         m_width = m_height = 0;
         m_countVisible = 0;

include/wx/clipbrd.h

@@ -168,7 +168,7 @@ typedef void (wxEvtHandler::*wxClipboardEventFunction)(wxClipboardEvent&);
 class WXDLLIMPEXP_CORE wxClipboardLocker
 {
 public:
-    wxClipboardLocker(wxClipboard *clipboard = NULL)
+    wxClipboardLocker(wxClipboard *clipboard = nullptr)
     {
         m_clipboard = clipboard ? clipboard : wxTheClipboard;
         if ( m_clipboard )

include/wx/clntdata.h

@@ -54,7 +54,7 @@ public:
         return true;
     }
 
-    void AddField( const wxString &name, void* initialValue = NULL )
+    void AddField( const wxString &name, void* initialValue = nullptr )
     {
         wxShadowObjectFields::iterator it = m_fields.find( name );
         if (it == m_fields.end())
@@ -71,7 +71,7 @@ public:
         it->second = value;
     }
 
-    void* GetField( const wxString &name, void *defaultValue = NULL )
+    void* GetField( const wxString &name, void *defaultValue = nullptr )
     {
         wxShadowObjectFields::iterator it = m_fields.find( name );
         if (it == m_fields.end())
@@ -180,7 +180,7 @@ public:
     void *GetClientData() const;
 
 protected:
-    bool HasClientDataContainer() const { return m_data.get() != NULL; }
+    bool HasClientDataContainer() const { return m_data.get() != nullptr; }
     void CopyClientDataContainer(const wxSharedClientDataContainer& other)
     {
         m_data = other.m_data;
@@ -192,7 +192,7 @@ private:
     {
     };
 
-    // Helper function that will create m_data if it is currently NULL
+    // Helper function that will create m_data if it is currently null
     wxClientDataContainer *GetValidClientData();
 
     // m_data is shared, not deep copied, when cloned. If you make changes to

include/wx/cmdargs.h

@@ -28,7 +28,7 @@
 class WXDLLIMPEXP_BASE wxCmdLineArgsArray
 {
 public:
-    wxCmdLineArgsArray() { m_argsA = NULL; m_argsW = NULL; }
+    wxCmdLineArgsArray() { m_argsA = nullptr; m_argsW = nullptr; }
 
     template <typename T>
     void Init(int argc, T **argv)
@@ -53,7 +53,7 @@ public:
             for ( size_t n = 0; n < count; n++ )
                 m_argsA[n] = wxStrdup(m_args[n].ToAscii());
 
-            m_argsA[count] = NULL;
+            m_argsA[count] = nullptr;
         }
 
         return m_argsA;
@@ -68,7 +68,7 @@ public:
             for ( size_t n = 0; n < count; n++ )
                 m_argsW[n] = wxStrdup(m_args[n].wc_str());
 
-            m_argsW[count] = NULL;
+            m_argsW[count] = nullptr;
         }
 
         return m_argsW;
@@ -125,7 +125,7 @@ private:
             free(args[n]);
 
         delete [] args;
-        args = NULL;
+        args = nullptr;
     }
 
     void FreeArgs()

include/wx/cmdline.h

@@ -93,7 +93,7 @@ struct wxCmdLineEntryDesc
 
 // the list of wxCmdLineEntryDesc objects should be terminated with this one
 #define wxCMD_LINE_DESC_END \
-        { wxCMD_LINE_NONE, NULL, NULL, NULL, wxCMD_LINE_VAL_NONE, 0x0 }
+        { wxCMD_LINE_NONE, nullptr, nullptr, nullptr, wxCMD_LINE_VAL_NONE, 0x0 }
 
 // ----------------------------------------------------------------------------
 // wxCmdLineArg contains the value for one command line argument
@@ -141,7 +141,7 @@ public:
         typedef std::bidirectional_iterator_tag iterator_category;
 #endif // wx_USE_STD_STRING
 
-        const_iterator() : m_parser(NULL), m_index(0) {}
+        const_iterator() : m_parser(nullptr), m_index(0) {}
         reference operator *() const;
         pointer operator ->() const;
         const_iterator &operator ++ ();

include/wx/cmdproc.h

@@ -90,7 +90,7 @@ public:
     const wxList& GetCommands() const { return m_commands; }
     wxCommand *GetCurrentCommand() const
     {
-        return (wxCommand *)(m_currentCommand ? m_currentCommand->GetData() : NULL);
+        return (wxCommand *)(m_currentCommand ? m_currentCommand->GetData() : nullptr);
     }
     int GetMaxCommands() const { return m_maxNoCommands; }
     virtual void ClearCommands();

include/wx/colordlg.h

@@ -78,10 +78,10 @@ wxDECLARE_EXPORTED_EVENT(WXDLLIMPEXP_CORE, wxEVT_COLOUR_CHANGED, wxColourDialogE
 
 
 // get the colour from user and return it
-WXDLLIMPEXP_CORE wxColour wxGetColourFromUser(wxWindow *parent = NULL,
+WXDLLIMPEXP_CORE wxColour wxGetColourFromUser(wxWindow *parent = nullptr,
                                               const wxColour& colInit = wxNullColour,
                                               const wxString& caption = wxEmptyString,
-                                              wxColourData *data = NULL);
+                                              wxColourData *data = nullptr);
 
 #endif // wxUSE_COLOURDLG
 

include/wx/colour.h

@@ -206,14 +206,14 @@ protected:
     {
         wxFAIL_MSG( "must be overridden if used" );
 
-        return NULL;
+        return nullptr;
     }
 
     virtual wxGDIRefData *CloneGDIRefData(const wxGDIRefData *WXUNUSED(data)) const override
     {
         wxFAIL_MSG( "must be overridden if used" );
 
-        return NULL;
+        return nullptr;
     }
 #endif
 };

include/wx/combo.h

@@ -181,7 +181,7 @@ public:
     bool IsPopupShown() const { return m_popupWinState == Visible; }
 
     // set interface class instance derived from wxComboPopup
-    // NULL popup can be used to indicate default in a derived class
+    // null popup can be used to indicate default in a derived class
     void SetPopupControl( wxComboPopup* popup )
     {
         DoSetPopupControl(popup);
@@ -538,7 +538,7 @@ protected:
     virtual wxSize DoGetBestSize() const override;
     virtual wxSize DoGetSizeFromTextSize(int xlen, int ylen = -1) const override;
 
-    // NULL popup can be used to indicate default in a derived class
+    // null popup can be used to indicate default in a derived class
     virtual void DoSetPopupControl(wxComboPopup* popup);
 
     // ensures there is at least the default popup
@@ -674,7 +674,7 @@ protected:
     wxRect                  m_tcArea;
     wxRect                  m_btnArea;
 
-    // Colour of the text area, in case m_text is NULL
+    // Colour of the text area, in case m_text is null
     wxColour                m_tcBgCol;
 
     // current button state (uses renderer flags)
@@ -752,7 +752,7 @@ class WXDLLIMPEXP_CORE wxComboPopup
 public:
     wxComboPopup()
     {
-        m_combo = NULL;
+        m_combo = nullptr;
         m_iFlags = 0;
     }
 
@@ -796,7 +796,7 @@ public:
     // implementation. If the found item matched the string, but is
     // different, it should be written back to pItem. Default implementation
     // always return true and does not alter trueItem.
-    virtual bool FindItem(const wxString& item, wxString* trueItem=NULL);
+    virtual bool FindItem(const wxString& item, wxString* trueItem=nullptr);
 
     // This is called to custom paint in the combo control itself (ie. not the popup).
     // Default implementation draws value as string.

include/wx/compositewin.h

@@ -147,7 +147,7 @@ private:
         {
             wxWindow * const child = *i;
 
-            // Allow NULL elements in the list, this makes the code of derived
+            // Allow null elements in the list, this makes the code of derived
             // composite controls which may have optionally shown children
             // simpler and it doesn't cost us much here.
             if ( child )
@@ -165,7 +165,7 @@ class wxCompositeWindow : public wxCompositeWindowSettersOnly<W>
 public:
     virtual void SetFocus() override
     {
-        wxSetFocusToChild(this, NULL);
+        wxSetFocusToChild(this, nullptr);
     }
 
 protected:

include/wx/confbase.h

@@ -104,7 +104,7 @@ public:
     // comments near definition wxUSE_CONFIG_NATIVE for details. It returns
     // the created object and also sets it as ms_pConfig.
   static wxConfigBase *Create();
-    // should Get() try to create a new log object if the current one is NULL?
+    // should Get() try to create a new log object if the current one is null?
   static void DontCreateOnDemand() { ms_bAutoCreate = false; }
 
   // ctor & virtual dtor

include/wx/containr.h

@@ -39,13 +39,13 @@ public:
     // default ctor, SetContainerWindow() must be called later
     wxControlContainerBase()
     {
-        m_winParent = NULL;
+        m_winParent = nullptr;
 
         // By default, we accept focus ourselves.
         m_acceptsFocusSelf = true;
 
         m_inSetFocus = false;
-        m_winLastFocused = NULL;
+        m_winLastFocused = nullptr;
     }
     virtual ~wxControlContainerBase() {}
 

include/wx/control.h

@@ -145,9 +145,9 @@ public:
                               int flags = wxELLIPSIZE_FLAGS_DEFAULT);
 
     // return the accel index in the string or -1 if none and puts the modified
-    // string into second parameter if non NULL
+    // string into second parameter if non-null
     static int FindAccelIndex(const wxString& label,
-                              wxString *labelOnly = NULL);
+                              wxString *labelOnly = nullptr);
 
     // this is a helper for the derived class GetClassDefaultAttributes()
     // implementation: it returns the right colours for the classes which

include/wx/convauto.h

@@ -107,7 +107,7 @@ private:
     {
         // We don't initialize m_encDefault here as different ctors do it
         // differently.
-        m_conv = NULL;
+        m_conv = nullptr;
         m_bomType = wxBOM_Unknown;
         m_ownsConv = false;
         m_consumedBOM = false;
@@ -139,7 +139,7 @@ private:
     // wxFONTENCODING_MAX but not wxFONTENCODING_DEFAULT
     static wxFontEncoding ms_defaultMBEncoding;
 
-    // conversion object which we really use, NULL until the first call to
+    // conversion object which we really use, null until the first call to
     // either ToWChar() or FromWChar()
     wxMBConv *m_conv;
 

include/wx/cpp.h

@@ -109,7 +109,7 @@
 
 /*
     Define __WXFUNCTION__ which is like standard __FUNCTION__ but defined as
-    NULL for the compilers which don't support the latter.
+    nullptr for the compilers which don't support the latter.
  */
 #ifndef __WXFUNCTION__
     #if defined(__GNUC__) || \
@@ -118,7 +118,7 @@
         #define __WXFUNCTION__ __FUNCTION__
     #else
         /* still define __WXFUNCTION__ to avoid #ifdefs elsewhere */
-        #define __WXFUNCTION__ (NULL)
+        #define __WXFUNCTION__ (nullptr)
     #endif
 #endif /* __WXFUNCTION__ already defined */
 

include/wx/cshelp.h

@@ -38,7 +38,7 @@
 class WXDLLIMPEXP_CORE wxContextHelp : public wxObject
 {
 public:
-    wxContextHelp(wxWindow* win = NULL, bool beginHelp = true);
+    wxContextHelp(wxWindow* win = nullptr, bool beginHelp = true);
     virtual ~wxContextHelp();
 
     bool BeginContextHelp(wxWindow* win);
@@ -146,7 +146,7 @@ public:
                                  const wxPoint& pt,
                                  wxHelpEvent::Origin origin)
     {
-        wxCHECK_MSG( window, false, wxT("window must not be NULL") );
+        wxCHECK_MSG( window, false, wxT("window must not be null") );
 
         m_helptextAtPoint = pt;
         m_helptextOrigin = origin;
@@ -229,7 +229,7 @@ class WXDLLIMPEXP_CORE wxHelpControllerHelpProvider : public wxSimpleHelpProvide
 public:
     // Note that it doesn't own the help controller. The help controller
     // should be deleted separately.
-    wxHelpControllerHelpProvider(wxHelpControllerBase* hc = NULL);
+    wxHelpControllerHelpProvider(wxHelpControllerBase* hc = nullptr);
 
     // implement wxHelpProvider methods
 

include/wx/ctrlsub.h

@@ -119,7 +119,7 @@ private:
 
     int AppendItems(const wxArrayStringsAdapter& items)
     {
-        return AppendItems(items, NULL, wxClientData_None);
+        return AppendItems(items, nullptr, wxClientData_None);
     }
 
     int AppendItems(const wxArrayStringsAdapter& items, void **clientData)
@@ -162,7 +162,7 @@ private:
 
     int InsertItems(const wxArrayStringsAdapter& items, unsigned int pos)
     {
-        return InsertItems(items, pos, NULL, wxClientData_None);
+        return InsertItems(items, pos, nullptr, wxClientData_None);
     }
 
     int InsertItems(const wxArrayStringsAdapter& items,
@@ -316,7 +316,7 @@ public:
     // SetClientObject() takes ownership of the pointer, GetClientObject()
     // returns it but keeps the ownership while DetachClientObject() expects
     // the caller to delete the pointer and also resets the internally stored
-    // one to NULL for this item
+    // one to nullptr for this item
     void SetClientObject(unsigned int n, wxClientData* clientData);
     wxClientData* GetClientObject(unsigned int n) const;
     wxClientData* DetachClientObject(unsigned int n);
@@ -397,7 +397,7 @@ protected:
                                  wxClientDataType type);
 
     // free the client object associated with the item at given position and
-    // set it to NULL (must only be called if HasClientObjectData())
+    // set it to nullptr (must only be called if HasClientObjectData())
     void ResetItemClientObject(unsigned int n);
 
     // set the type of the client data stored in this control: override this if

include/wx/dataobj.h

@@ -268,7 +268,7 @@ public:
     // out what kind of data object was received.
     wxDataFormat GetReceivedFormat() const;
 
-    // Returns the pointer to the object which supports this format or NULL.
+    // Returns the pointer to the object which supports this format or nullptr.
     // The returned pointer is owned by wxDataObjectComposite and must
     // therefore not be destroyed by the caller.
     wxDataObjectSimple *GetObject(const wxDataFormat& format,

include/wx/dataview.h

@@ -108,8 +108,8 @@ WX_DEFINE_ARRAY(wxDataViewItem, wxDataViewItemArray);
 class WXDLLIMPEXP_CORE wxDataViewModelNotifier
 {
 public:
-    wxDataViewModelNotifier() { m_owner = NULL; }
+    wxDataViewModelNotifier() { m_owner = nullptr; }
-    virtual ~wxDataViewModelNotifier() { m_owner = NULL; }
+    virtual ~wxDataViewModelNotifier() { m_owner = nullptr; }
 
     virtual bool ItemAdded( const wxDataViewItem &parent, const wxDataViewItem &item ) = 0;
     virtual bool ItemDeleted( const wxDataViewItem &parent, const wxDataViewItem &item ) = 0;
@@ -723,10 +723,10 @@ public:
     wxDataViewItem GetCurrentItem() const;
     void SetCurrentItem(const wxDataViewItem& item);
 
-    virtual wxDataViewItem GetTopItem() const { return wxDataViewItem(NULL); }
+    virtual wxDataViewItem GetTopItem() const { return wxDataViewItem(nullptr); }
     virtual int GetCountPerPage() const { return wxNOT_FOUND; }
 
-    // Currently focused column of the current item or NULL if no column has focus
+    // Currently focused column of the current item or nullptr if no column has focus
     virtual wxDataViewColumn *GetCurrentColumn() const = 0;
 
     // Selection: both GetSelection() and GetSelections() can be used for the
@@ -754,9 +754,9 @@ public:
     virtual bool IsExpanded( const wxDataViewItem & item ) const = 0;
 
     virtual void EnsureVisible( const wxDataViewItem & item,
-                                const wxDataViewColumn *column = NULL ) = 0;
+                                const wxDataViewColumn *column = nullptr ) = 0;
     virtual void HitTest( const wxPoint & point, wxDataViewItem &item, wxDataViewColumn* &column ) const = 0;
-    virtual wxRect GetItemRect( const wxDataViewItem & item, const wxDataViewColumn *column = NULL ) const = 0;
+    virtual wxRect GetItemRect( const wxDataViewItem & item, const wxDataViewColumn *column = nullptr ) const = 0;
 
     virtual bool SetRowHeight( int WXUNUSED(rowHeight) ) { return false; }
 
@@ -857,7 +857,7 @@ public:
     wxDataViewEvent()
         : wxNotifyEvent()
     {
-        Init(NULL, NULL, wxDataViewItem());
+        Init(nullptr, nullptr, wxDataViewItem());
     }
 
     // Constructor for the events affecting columns (and possibly also items).
@@ -876,7 +876,7 @@ public:
                     const wxDataViewItem& item)
         : wxNotifyEvent(evtType, dvc->GetId())
     {
-        Init(dvc, NULL, item);
+        Init(dvc, nullptr, item);
     }
 
     wxDataViewEvent(const wxDataViewEvent& event)
@@ -1241,7 +1241,7 @@ public:
     wxDataViewTreeStoreNode( wxDataViewTreeStoreNode *parent,
         const wxString &text,
         const wxBitmapBundle &icon = wxBitmapBundle(),
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
     virtual ~wxDataViewTreeStoreNode();
 
     void SetText( const wxString &text )
@@ -1284,7 +1284,7 @@ public:
         const wxString &text,
         const wxBitmapBundle &icon = wxBitmapBundle(),
         const wxBitmapBundle &expanded = wxBitmapBundle(),
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
     virtual ~wxDataViewTreeStoreContainerNode();
 
     const wxDataViewTreeStoreNodes &GetChildren() const
@@ -1328,31 +1328,31 @@ public:
     wxDataViewItem AppendItem( const wxDataViewItem& parent,
         const wxString &text,
         const wxBitmapBundle &icon = wxBitmapBundle(),
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
     wxDataViewItem PrependItem( const wxDataViewItem& parent,
         const wxString &text,
         const wxBitmapBundle &icon = wxBitmapBundle(),
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
     wxDataViewItem InsertItem( const wxDataViewItem& parent, const wxDataViewItem& previous,
         const wxString &text,
         const wxBitmapBundle &icon = wxBitmapBundle(),
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
 
     wxDataViewItem PrependContainer( const wxDataViewItem& parent,
         const wxString &text,
         const wxBitmapBundle &icon = wxBitmapBundle(),
         const wxBitmapBundle &expanded = wxBitmapBundle(),
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
     wxDataViewItem AppendContainer( const wxDataViewItem& parent,
         const wxString &text,
         const wxBitmapBundle &icon = wxBitmapBundle(),
         const wxBitmapBundle &expanded = wxBitmapBundle(),
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
     wxDataViewItem InsertContainer( const wxDataViewItem& parent, const wxDataViewItem& previous,
         const wxString &text,
         const wxBitmapBundle &icon = wxBitmapBundle(),
         const wxBitmapBundle &expanded = wxBitmapBundle(),
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
 
     wxDataViewItem GetNthChild( const wxDataViewItem& parent, unsigned int pos ) const;
     int GetChildCount( const wxDataViewItem& parent ) const;
@@ -1429,21 +1429,21 @@ public:
         { return GetStore()->IsContainer(item); }
 
     wxDataViewItem AppendItem( const wxDataViewItem& parent,
-        const wxString &text, int icon = NO_IMAGE, wxClientData *data = NULL );
+        const wxString &text, int icon = NO_IMAGE, wxClientData *data = nullptr );
     wxDataViewItem PrependItem( const wxDataViewItem& parent,
-        const wxString &text, int icon = NO_IMAGE, wxClientData *data = NULL );
+        const wxString &text, int icon = NO_IMAGE, wxClientData *data = nullptr );
     wxDataViewItem InsertItem( const wxDataViewItem& parent, const wxDataViewItem& previous,
-        const wxString &text, int icon = NO_IMAGE, wxClientData *data = NULL );
+        const wxString &text, int icon = NO_IMAGE, wxClientData *data = nullptr );
 
     wxDataViewItem PrependContainer( const wxDataViewItem& parent,
         const wxString &text, int icon = NO_IMAGE, int expanded = NO_IMAGE,
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
     wxDataViewItem AppendContainer( const wxDataViewItem& parent,
         const wxString &text, int icon = NO_IMAGE, int expanded = NO_IMAGE,
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
     wxDataViewItem InsertContainer( const wxDataViewItem& parent, const wxDataViewItem& previous,
         const wxString &text, int icon = NO_IMAGE, int expanded = NO_IMAGE,
-        wxClientData *data = NULL );
+        wxClientData *data = nullptr );
 
     wxDataViewItem GetNthChild( const wxDataViewItem& parent, unsigned int pos ) const
         { return GetStore()->GetNthChild(parent, pos); }

include/wx/datetime.h

@@ -927,7 +927,7 @@ public:
 
     // all conversions functions return true to indicate whether parsing
     // succeeded or failed and fill in the provided end iterator, which must
-    // not be NULL, with the location of the character where the parsing
+    // not be null, with the location of the character where the parsing
     // stopped (this will be end() of the passed string if everything was
     // parsed)
 
@@ -1021,7 +1021,7 @@ public:
 
     // backwards compatible versions of the parsing functions: they return an
     // object representing the next character following the date specification
-    // (i.e. the one where the scan had to stop) or a special NULL-like object
+    // (i.e. the one where the scan had to stop) or a special nullptr-like object
     // on failure
     //
     // they're not deprecated because a lot of existing code uses them and
@@ -1120,7 +1120,7 @@ public:
     inline wxLongLong GetValue() const;
 
     // a helper function to get the current time_t
-    static time_t GetTimeNow() { return time(NULL); }
+    static time_t GetTimeNow() { return time(nullptr); }
 
     // another one to get the current time broken down
     static struct tm *GetTmNow()

include/wx/dc.h

@@ -183,10 +183,10 @@ public:
     // get Cairo context
     virtual void* GetCairoContext() const
     {
-        return NULL;
+        return nullptr;
     }
 
-    virtual void* GetHandle() const { return NULL; }
+    virtual void* GetHandle() const { return nullptr; }
 
     // query dimension, colour deps, resolution
 
@@ -347,14 +347,14 @@ public:
 
     virtual void DoGetTextExtent(const wxString& string,
                                  wxCoord *x, wxCoord *y,
-                                 wxCoord *descent = NULL,
+                                 wxCoord *descent = nullptr,
-                                 wxCoord *externalLeading = NULL,
+                                 wxCoord *externalLeading = nullptr,
-                                 const wxFont *theFont = NULL) const = 0;
+                                 const wxFont *theFont = nullptr) const = 0;
     virtual void GetMultiLineTextExtent(const wxString& string,
                                         wxCoord *width,
                                         wxCoord *height,
-                                        wxCoord *heightLine = NULL,
+                                        wxCoord *heightLine = nullptr,
-                                        const wxFont *font = NULL) const;
+                                        const wxFont *font = nullptr) const;
     virtual bool DoGetPartialTextExtents(const wxString& text, wxArrayInt& widths) const;
 
     // clearing
@@ -592,7 +592,7 @@ public:
 
 #if wxUSE_GRAPHICS_CONTEXT
     virtual wxGraphicsContext* GetGraphicsContext() const
-        { return NULL; }
+        { return nullptr; }
     virtual void SetGraphicsContext( wxGraphicsContext* WXUNUSED(ctx) )
         {}
 #endif
@@ -627,7 +627,7 @@ protected:
     double GetMMToPXy() const;
 
 
-    // window on which the DC draws or NULL
+    // window on which the DC draws or nullptr
     wxWindow   *m_window;
 
     // flags
@@ -876,9 +876,9 @@ public:
 
     void GetTextExtent(const wxString& string,
                        wxCoord *x, wxCoord *y,
-                       wxCoord *descent = NULL,
+                       wxCoord *descent = nullptr,
-                       wxCoord *externalLeading = NULL,
+                       wxCoord *externalLeading = nullptr,
-                       const wxFont *theFont = NULL) const
+                       const wxFont *theFont = nullptr) const
         { m_pimpl->DoGetTextExtent(string, x, y, descent, externalLeading, theFont); }
 
     wxSize GetTextExtent(const wxString& string) const
@@ -891,8 +891,8 @@ public:
     void GetMultiLineTextExtent(const wxString& string,
                                         wxCoord *width,
                                         wxCoord *height,
-                                        wxCoord *heightLine = NULL,
+                                        wxCoord *heightLine = nullptr,
-                                        const wxFont *font = NULL) const
+                                        const wxFont *font = nullptr) const
         { m_pimpl->GetMultiLineTextExtent( string, width, height, heightLine, font ); }
 
     wxSize GetMultiLineTextExtent(const wxString& string) const
@@ -1190,7 +1190,7 @@ public:
                            const wxRect& rect,
                            int alignment = wxALIGN_LEFT | wxALIGN_TOP,
                            int indexAccel = -1,
-                           wxRect *rectBounding = NULL);
+                           wxRect *rectBounding = nullptr);
 
     void DrawLabel(const wxString& text, const wxRect& rect,
                    int alignment = wxALIGN_LEFT | wxALIGN_TOP,
@@ -1234,7 +1234,7 @@ public:
                       source, srcPt.x, srcPt.y, srcSize.x, srcSize.y, rop, useMask, srcMaskPt.x, srcMaskPt.y);
     }
 
-    wxBitmap GetAsBitmap(const wxRect *subrect = (const wxRect *) NULL) const
+    wxBitmap GetAsBitmap(const wxRect *subrect = (const wxRect *) nullptr) const
     {
         return m_pimpl->DoGetAsBitmap(subrect);
     }
@@ -1276,7 +1276,7 @@ public:
             : m_dc(thdc.m_dc),
               m_hdc(thdc.m_hdc)
         {
-            const_cast<TempHDC&>(thdc).m_hdc = NULL;
+            const_cast<TempHDC&>(thdc).m_hdc = nullptr;
         }
 
         ~TempHDC()

include/wx/dcbuffer.h

@@ -40,8 +40,8 @@ class WXDLLIMPEXP_CORE wxBufferedDC : public wxMemoryDC
 public:
     // Default ctor, must subsequently call Init for two stage construction.
     wxBufferedDC()
-        : m_dc(NULL),
+        : m_dc(nullptr),
-          m_buffer(NULL),
+          m_buffer(nullptr),
           m_style(0)
     {
     }
@@ -50,7 +50,7 @@ public:
     wxBufferedDC(wxDC *dc,
                  wxBitmap& buffer = wxNullBitmap,
                  int style = wxBUFFER_CLIENT_AREA)
-        : m_dc(NULL), m_buffer(NULL)
+        : m_dc(nullptr), m_buffer(nullptr)
     {
         Init(dc, buffer, style);
     }
@@ -59,7 +59,7 @@ public:
     // (where area is usually something like the size of the window
     // being buffered)
     wxBufferedDC(wxDC *dc, const wxSize& area, int style = wxBUFFER_CLIENT_AREA)
-        : m_dc(NULL), m_buffer(NULL)
+        : m_dc(nullptr), m_buffer(nullptr)
     {
         Init(dc, area, style);
     }

include/wx/dcgraph.h

@@ -209,9 +209,9 @@ public:
 
     virtual void DoGetTextExtent(const wxString& string,
         wxCoord *x, wxCoord *y,
-        wxCoord *descent = NULL,
+        wxCoord *descent = nullptr,
-        wxCoord *externalLeading = NULL,
+        wxCoord *externalLeading = nullptr,
-        const wxFont *theFont = NULL) const override;
+        const wxFont *theFont = nullptr) const override;
 
     virtual bool DoGetPartialTextExtents(const wxString& text, wxArrayInt& widths) const override;
 

include/wx/dcmirror.h

@@ -86,7 +86,7 @@ protected:
     // exchange x and y components of all points in the array if necessary
     wxPoint* Mirror(int n, const wxPoint*& points) const
     {
-        wxPoint* points_alloc = NULL;
+        wxPoint* points_alloc = nullptr;
         if ( m_mirror )
         {
             points_alloc = new wxPoint[n];
@@ -256,9 +256,9 @@ protected:
 
     virtual void DoGetTextExtent(const wxString& string,
                                  wxCoord *x, wxCoord *y,
-                                 wxCoord *descent = NULL,
+                                 wxCoord *descent = nullptr,
-                                 wxCoord *externalLeading = NULL,
+                                 wxCoord *externalLeading = nullptr,
-                                 const wxFont *theFont = NULL) const override
+                                 const wxFont *theFont = nullptr) const override
     {
         // never mirrored
         m_dc.DoGetTextExtent(string, x, y, descent, externalLeading, theFont);

include/wx/dcscreen.h

@@ -21,7 +21,7 @@ public:
 
     static bool StartDrawingOnTop(wxWindow * WXUNUSED(window))
         { return true; }
-    static bool StartDrawingOnTop(wxRect * WXUNUSED(rect) =  NULL)
+    static bool StartDrawingOnTop(wxRect * WXUNUSED(rect) =  nullptr)
         { return true; }
     static bool EndDrawingOnTop()
         { return true; }

include/wx/dcsvg.h

@@ -135,7 +135,7 @@ public:
     virtual void SetFont(const wxFont& font) override;
     virtual void SetPen(const wxPen& pen) override;
 
-    virtual void* GetHandle() const override { return NULL; }
+    virtual void* GetHandle() const override { return nullptr; }
 
     void SetBitmapHandler(wxSVGBitmapHandler* handler);
 
@@ -235,9 +235,9 @@ private:
 
     virtual void DoGetTextExtent(const wxString& string,
                                  wxCoord* x, wxCoord* y,
-                                 wxCoord* descent = NULL,
+                                 wxCoord* descent = nullptr,
-                                 wxCoord* externalLeading = NULL,
+                                 wxCoord* externalLeading = nullptr,
-                                 const wxFont* theFont = NULL) const override;
+                                 const wxFont* theFont = nullptr) const override;
 
     virtual void DoSetDeviceClippingRegion(const wxRegion& region) override;
 

include/wx/debug.h

@@ -81,7 +81,7 @@ typedef void (*wxAssertHandler_t)(const wxString& file,
 
 #if wxDEBUG_LEVEL
 
-// the global assert handler function, if it is NULL asserts don't check their
+// the global assert handler function, if it is null asserts don't check their
 // conditions
 extern WXDLLIMPEXP_DATA_BASE(wxAssertHandler_t) wxTheAssertHandler;
 
@@ -99,7 +99,7 @@ extern WXDLLIMPEXP_DATA_BASE(wxAssertHandler_t) wxTheAssertHandler;
     need to provide your assertion handler function.
 
     This function also provides a simple way to disable all asserts: simply
-    pass NULL pointer to it. Doing this will result in not even evaluating
+    pass null pointer to it. Doing this will result in not even evaluating
     assert conditions at all, avoiding almost all run-time cost of asserts.
 
     Notice that this function is not MT-safe, so you should call it before
@@ -132,15 +132,15 @@ extern void WXDLLIMPEXP_BASE wxSetDefaultAssertHandler();
 //     defined
 inline wxAssertHandler_t wxSetAssertHandler(wxAssertHandler_t /* handler */)
 {
-    return NULL;
+    return nullptr;
 }
 
 inline void wxSetDefaultAssertHandler() { }
 
 #endif // wxDEBUG_LEVEL/!wxDEBUG_LEVEL
 
-// simply a synonym for wxSetAssertHandler(NULL)
+// simply a synonym for wxSetAssertHandler(nullptr)
-inline void wxDisableAsserts() { wxSetAssertHandler(NULL); }
+inline void wxDisableAsserts() { wxSetAssertHandler(nullptr); }
 
 /*
     A macro which disables asserts for applications compiled in release build.
@@ -162,7 +162,7 @@ inline void wxDisableAsserts() { wxSetAssertHandler(NULL); }
     overloads are needed because these macros can be used with or without wxT().
 
     All of them are implemented in src/common/appcmn.cpp and unconditionally
-    call wxTheAssertHandler so the caller must check that it is non-NULL
+    call wxTheAssertHandler so the caller must check that it is non-null
     (assert macros do it).
  */
 
@@ -170,7 +170,7 @@ inline void wxDisableAsserts() { wxSetAssertHandler(NULL); }
 
 // these overloads are the ones typically used by debugging macros: we have to
 // provide wxChar* msg version because it's common to use wxT() in the macros
-// and finally, we can't use const wx(char)* msg = NULL, because that would
+// and finally, we can't use const wx(char)* msg = nullptr, because that would
 // be ambiguous
 //
 // also notice that these functions can't be inline as wxString is not defined
@@ -200,7 +200,7 @@ extern WXDLLIMPEXP_BASE void wxOnAssert(const wxChar *file,
                                         int line,
                                         const char *func,
                                         const wxChar *cond,
-                                        const wxChar *msg = NULL);
+                                        const wxChar *msg = nullptr);
 
 // these overloads work when msg passed to debug macro is a string and we
 // also have to provide wxCStrData overload to resolve ambiguity which would
@@ -300,7 +300,7 @@ extern WXDLLIMPEXP_BASE void wxOnAssert(const char *file,
 
     // a version without any additional message, don't use unless condition
     // itself is fully self-explanatory
-    #define wxASSERT(cond) wxASSERT_MSG(cond, (const char*)NULL)
+    #define wxASSERT(cond) wxASSERT_MSG(cond, (const char*)nullptr)
 
     // wxFAIL is a special form of assert: it always triggers (and so is
     // usually used in normally unreachable code)
@@ -322,7 +322,7 @@ extern WXDLLIMPEXP_BASE void wxOnAssert(const char *file,
         wxFAIL_COND_MSG_AT(cond, msg, __FILE__, __LINE__, __WXFUNCTION__)
 
     #define wxFAIL_MSG(msg) wxFAIL_COND_MSG("Assert failure", msg)
-    #define wxFAIL wxFAIL_MSG((const char*)NULL)
+    #define wxFAIL wxFAIL_MSG((const char*)nullptr)
 #else // !wxDEBUG_LEVEL
     #define wxTrap()
 
@@ -357,10 +357,10 @@ extern void WXDLLIMPEXP_BASE wxAbort();
     debug level 1 -- they call the assert handler if the condition is false
 
     They are supposed to be used only in invalid situation: for example, an
-    invalid parameter (e.g. a NULL pointer) is passed to a function. Instead of
+    invalid parameter (e.g. a null pointer) is passed to a function. Instead of
     dereferencing it and causing core dump the function might use
 
-        wxCHECK_RET( p != NULL, "pointer can't be NULL" )
+        wxCHECK_RET( p != nullptr, "pointer can't be null" )
 */
 
 // the generic macro: takes the condition to check, the statement to be executed
@@ -379,10 +379,10 @@ extern void WXDLLIMPEXP_BASE wxAbort();
 #define wxCHECK_MSG(cond, rc, msg)   wxCHECK2_MSG(cond, return rc, msg)
 
 // check that expression is true, "return" if not (also FAILs in debug mode)
-#define wxCHECK(cond, rc)            wxCHECK_MSG(cond, rc, (const char*)NULL)
+#define wxCHECK(cond, rc)            wxCHECK_MSG(cond, rc, (const char*)nullptr)
 
 // check that expression is true, perform op if not
-#define wxCHECK2(cond, op)           wxCHECK2_MSG(cond, op, (const char*)NULL)
+#define wxCHECK2(cond, op)           wxCHECK2_MSG(cond, op, (const char*)nullptr)
 
 // special form of wxCHECK2: as wxCHECK, but for use in void functions
 //

include/wx/defs.h

@@ -707,9 +707,7 @@ typedef short int WXTYPE;
         wxDEPRECATED(func) { body }
 #endif
 
-/*  NULL declaration: it must be defined as 0 for C++ programs (in particular, */
+/* Get size_t declaration. */
-/*  it must not be defined as "(void *)0" which is standard for C but completely */
-/*  breaks C++ code) */
 #include <stddef.h>
 
 /*  size of statically declared array */
@@ -852,29 +850,29 @@ typedef short int WXTYPE;
 // everybody gets the assert and other debug macros
 #include "wx/debug.h"
 
-    // delete pointer if it is not NULL and NULL it afterwards
+    // delete pointer if it is not null and null it afterwards
     template <typename T>
     inline void wxDELETE(T*& ptr)
     {
         typedef char TypeIsCompleteCheck[sizeof(T)] WX_ATTRIBUTE_UNUSED;
 
-        if ( ptr != NULL )
+        if ( ptr != nullptr )
         {
             delete ptr;
-            ptr = NULL;
+            ptr = nullptr;
         }
     }
 
-    // delete an array and NULL it (see comments above)
+    // delete an array and null it (see comments above)
     template <typename T>
     inline void wxDELETEA(T*& ptr)
     {
         typedef char TypeIsCompleteCheck[sizeof(T)] WX_ATTRIBUTE_UNUSED;
 
-        if ( ptr != NULL )
+        if ( ptr != nullptr )
         {
             delete [] ptr;
-            ptr = NULL;
+            ptr = nullptr;
         }
     }
 
@@ -973,16 +971,10 @@ typedef double wxDouble;
 #endif /* wxWCHAR_T_IS_REAL_TYPE/!wxWCHAR_T_IS_REAL_TYPE */
 
 /*
-   This constant should be used instead of NULL in vararg functions taking
+   Deprecated constant existing only for compatibility, use nullptr directly in
-   wxChar* arguments: passing NULL (which is the same as 0, unless the compiler
+   the new code.
-   defines it specially, e.g. like gcc does with its __null built-in) doesn't
-   work in this case as va_arg() wouldn't interpret the integer 0 correctly
-   when trying to convert it to a pointer on architectures where sizeof(int) is
-   strictly less than sizeof(void *).
-
-   Examples of places where this must be used include wxFileTypeInfo ctor.
  */
-#define wxNullPtr ((void *)NULL)
+#define wxNullPtr nullptr
 
 
 /* Define wxChar16 and wxChar32                                              */

include/wx/dfb/bitmap.h

@@ -59,7 +59,7 @@ public:
     virtual wxBitmap GetSubBitmap(const wxRect& rect) const;
 
     virtual bool SaveFile(const wxString &name, wxBitmapType type,
-                          const wxPalette *palette = NULL) const;
+                          const wxPalette *palette = nullptr) const;
     virtual bool LoadFile(const wxString &name, wxBitmapType type = wxBITMAP_DEFAULT_TYPE);
 
 #if wxUSE_PALETTE

include/wx/dfb/dc.h

@@ -25,14 +25,14 @@ class WXDLLIMPEXP_CORE wxDFBDCImpl : public wxDCImpl
 {
 public:
     // ctors
-    wxDFBDCImpl(wxDC *owner) : wxDCImpl(owner) { m_surface = NULL; }
+    wxDFBDCImpl(wxDC *owner) : wxDCImpl(owner) { m_surface = nullptr; }
     wxDFBDCImpl(wxDC *owner, const wxIDirectFBSurfacePtr& surface)
         : wxDCImpl(owner)
     {
         DFBInit(surface);
     }
 
-    bool IsOk() const { return m_surface != NULL; }
+    bool IsOk() const { return m_surface != nullptr; }
 
     // implement base class pure virtuals
     // ----------------------------------
@@ -62,9 +62,9 @@ public:
     virtual wxCoord GetCharWidth() const;
     virtual void DoGetTextExtent(const wxString& string,
                                  wxCoord *x, wxCoord *y,
-                                 wxCoord *descent = NULL,
+                                 wxCoord *descent = nullptr,
-                                 wxCoord *externalLeading = NULL,
+                                 wxCoord *externalLeading = nullptr,
-                                 const wxFont *theFont = NULL) const;
+                                 const wxFont *theFont = nullptr) const;
 
     virtual bool CanDrawBitmap() const { return true; }
     virtual bool CanGetTextExtent() const { return true; }

include/wx/dfb/dcclient.h

@@ -26,7 +26,7 @@ public:
     virtual ~wxWindowDCImpl();
 
 protected:
-    // initializes the DC for painting on given window; if rect!=NULL, then
+    // initializes the DC for painting on given window; if rect!=nullptr, then
     // for painting only on the given region of the window
     void InitForWin(wxWindow *win, const wxRect *rect);
 

include/wx/dfb/dfbptr.h

@@ -54,7 +54,7 @@ public:
 
         Takes ownership of @a ptr, i.e. AddRef() is @em not called on it.
      */
-    wxDfbPtr(T *ptr = NULL) : m_ptr(ptr) {}
+    wxDfbPtr(T *ptr = nullptr) : m_ptr(ptr) {}
 
     /// Copy ctor
     wxDfbPtr(const wxDfbPtr& ptr) { InitFrom(ptr); }
@@ -62,13 +62,13 @@ public:
     /// Dtor. Releases the interface
     ~wxDfbPtr() { Reset(); }
 
-    /// Resets the pointer to NULL, decreasing reference count of the interface.
+    /// Resets the pointer to nullptr, decreasing reference count of the interface.
     void Reset()
     {
         if ( m_ptr )
         {
             this->DoRelease((wxDfbWrapperBase*)m_ptr);
-            m_ptr = NULL;
+            m_ptr = nullptr;
         }
     }
 

include/wx/dfb/window.h

@@ -72,7 +72,7 @@ public:
     virtual void WarpPointer(int x, int y);
 
     virtual void Refresh(bool eraseBackground = true,
-                         const wxRect *rect = (const wxRect *) NULL);
+                         const wxRect *rect = nullptr);
     virtual void Update();
 
     virtual bool SetCursor(const wxCursor &cursor);
@@ -105,9 +105,9 @@ protected:
     // implement the base class pure virtuals
     virtual void DoGetTextExtent(const wxString& string,
                                  int *x, int *y,
-                                 int *descent = NULL,
+                                 int *descent = nullptr,
-                                 int *externalLeading = NULL,
+                                 int *externalLeading = nullptr,
-                                 const wxFont *theFont = NULL) const;
+                                 const wxFont *theFont = nullptr) const;
     virtual void DoClientToScreen(int *x, int *y) const;
     virtual void DoScreenToClient(int *x, int *y) const;
     virtual void DoGetPosition(int *x, int *y) const;
@@ -178,7 +178,7 @@ private:
     // don't access it directly)
     wxRect m_rect;
 
-    // overlays for this window (or NULL if it doesn't have any)
+    // overlays for this window (or nullptr if it doesn't have any)
     wxDfbOverlaysList *m_overlays;
 
     friend class wxNonOwnedWindow; // for HandleXXXEvent

include/wx/dfb/wrapdfb.h

@@ -126,7 +126,7 @@ protected:
     The wrapper provides same API as DirectFB, with a few exceptions:
      - methods return true/false instead of error code
      - methods that return or create another interface return pointer to the
-       interface (or NULL on failure) instead of storing it in the last
+       interface (or nullptr on failure) instead of storing it in the last
        argument
      - interface arguments use wxFooPtr type instead of raw DirectFB pointer
      - methods taking flags use int type instead of an enum when the flags
@@ -245,9 +245,9 @@ struct wxIDirectFBSurface : public wxDfbWrapper<IDirectFBSurface>
 
     /**
         Updates the front buffer from the back buffer. If @a region is not
-        NULL, only given rectangle is updated.
+        nullptr, only given rectangle is updated.
      */
-    bool FlipToFront(const DFBRegion *region = NULL);
+    bool FlipToFront(const DFBRegion *region = nullptr);
 
     wxIDirectFBSurfacePtr GetSubSurface(const DFBRectangle *rect)
     {
@@ -255,7 +255,7 @@ struct wxIDirectFBSurface : public wxDfbWrapper<IDirectFBSurface>
         if ( Check(m_ptr->GetSubSurface(m_ptr, rect, &s)) )
             return new wxIDirectFBSurface(s);
         else
-            return NULL;
+            return nullptr;
     }
 
     wxIDirectFBPalettePtr GetPalette()
@@ -264,7 +264,7 @@ struct wxIDirectFBSurface : public wxDfbWrapper<IDirectFBSurface>
         if ( Check(m_ptr->GetPalette(m_ptr, &s)) )
             return new wxIDirectFBPalette(s);
         else
-            return NULL;
+            return nullptr;
     }
 
     bool SetPalette(const wxIDirectFBPalettePtr& pal)
@@ -336,7 +336,7 @@ struct wxIDirectFBSurface : public wxDfbWrapper<IDirectFBSurface>
             : m_surface(surface)
         {
             if ( !surface->Lock(flags, &ptr, &pitch) )
-                ptr = NULL;
+                ptr = nullptr;
         }
 
         ~Locked()
@@ -415,7 +415,7 @@ struct wxIDirectFBWindow : public wxDfbWrapper<IDirectFBWindow>
         if ( Check(m_ptr->GetSurface(m_ptr, &s)) )
             return new wxIDirectFBSurface(s);
         else
-            return NULL;
+            return nullptr;
     }
 
     bool AttachEventBuffer(const wxIDirectFBEventBufferPtr& buffer)
@@ -443,7 +443,7 @@ struct wxIDirectFBDisplayLayer : public wxDfbWrapper<IDirectFBDisplayLayer>
         if ( Check(m_ptr->CreateWindow(m_ptr, desc, &w)) )
             return new wxIDirectFBWindow(w);
         else
-            return NULL;
+            return nullptr;
     }
 
     bool GetConfiguration(DFBDisplayLayerConfig *config)
@@ -466,7 +466,7 @@ struct wxIDirectFBDisplayLayer : public wxDfbWrapper<IDirectFBDisplayLayer>
 struct wxIDirectFB : public wxDfbWrapper<IDirectFB>
 {
     /**
-        Returns pointer to DirectFB singleton object, it never returns NULL
+        Returns pointer to DirectFB singleton object, it never returns nullptr
         after wxApp was initialized. The object is cached, so calling this
         method is cheap.
      */
@@ -485,7 +485,7 @@ struct wxIDirectFB : public wxDfbWrapper<IDirectFB>
         if ( Check(m_ptr->CreateSurface(m_ptr, desc, &s)) )
             return new wxIDirectFBSurface(s);
         else
-            return NULL;
+            return nullptr;
     }
 
     wxIDirectFBEventBufferPtr CreateEventBuffer()
@@ -494,7 +494,7 @@ struct wxIDirectFB : public wxDfbWrapper<IDirectFB>
         if ( Check(m_ptr->CreateEventBuffer(m_ptr, &b)) )
             return new wxIDirectFBEventBuffer(b);
         else
-            return NULL;
+            return nullptr;
     }
 
     wxIDirectFBFontPtr CreateFont(const char *filename,
@@ -504,7 +504,7 @@ struct wxIDirectFB : public wxDfbWrapper<IDirectFB>
         if ( Check(m_ptr->CreateFont(m_ptr, filename, desc, &f)) )
             return new wxIDirectFBFont(f);
         else
-            return NULL;
+            return nullptr;
     }
 
     wxIDirectFBDisplayLayerPtr
@@ -514,7 +514,7 @@ struct wxIDirectFB : public wxDfbWrapper<IDirectFB>
         if ( Check(m_ptr->GetDisplayLayer(m_ptr, id, &l)) )
             return new wxIDirectFBDisplayLayer(l);
         else
-            return NULL;
+            return nullptr;
     }
 
     /// Returns primary surface

include/wx/dialog.h

@@ -104,7 +104,7 @@ public:
     // not set yet and hence must be passed explicitly to it so that we could
     // check whether it contains wxDIALOG_NO_PARENT bit.
     //
-    // This function always returns a valid top level window or NULL.
+    // This function always returns a valid top level window or nullptr.
     wxWindow *GetParentForModalDialog(wxWindow *parent, long style) const
     {
         return DoGetParentForDialog(wxDIALOG_MODALITY_APP_MODAL, parent, style);
@@ -142,7 +142,7 @@ public:
 
     // returns a horizontal wxBoxSizer containing the given buttons
     //
-    // notice that the returned sizer can be NULL if no buttons are put in the
+    // notice that the returned sizer can be null if no buttons are put in the
     // sizer (this mostly happens under smart phones and other atypical
     // platforms which have hardware buttons replacing OK/Cancel and such)
     wxSizer *CreateButtonSizer(long flags);
@@ -171,7 +171,7 @@ public:
 
     // Returns a content window if there is one. This can be used by the layout adapter, for
     // example to make the pages of a book control into scrolling windows
-    virtual wxWindow* GetContentWindow() const { return NULL; }
+    virtual wxWindow* GetContentWindow() const { return nullptr; }
 
     // Add an id to the list of main button identifiers that should be in the button sizer
     void AddMainButtonId(wxWindowID id) { m_mainButtonIds.Add((int) id); }
@@ -262,7 +262,7 @@ private:
                                    long style) const;
 
     // helper of DoGetParentForDialog(): returns the passed in window if it
-    // can be used as parent for this kind of dialog or NULL if it can't
+    // can be used as parent for this kind of dialog or nullptr if it can't
     wxWindow *CheckIfCanBeUsedAsParent(wxDialogModality modality,
                                        wxWindow *parent) const;
 
@@ -349,8 +349,8 @@ public:
 #endif // wxUSE_BUTTON
 
     // Reparent the controls to the scrolled window, except those in buttonSizer
-    virtual void ReparentControls(wxWindow* parent, wxWindow* reparentTo, wxSizer* buttonSizer = NULL);
+    virtual void ReparentControls(wxWindow* parent, wxWindow* reparentTo, wxSizer* buttonSizer = nullptr);
-    static void DoReparentControls(wxWindow* parent, wxWindow* reparentTo, wxSizer* buttonSizer = NULL);
+    static void DoReparentControls(wxWindow* parent, wxWindow* reparentTo, wxSizer* buttonSizer = nullptr);
 
     // A function to fit the dialog around its contents, and then adjust for screen size.
     // If scrolled windows are passed, scrolling is enabled in the required orientation(s).

include/wx/dir.h

@@ -96,7 +96,7 @@ public:
     // -----
 
     // default, use Open()
-    wxDir() { m_data = NULL; }
+    wxDir() { m_data = nullptr; }
 
     // opens the directory for enumeration, use IsOpened() to test success
     wxDir(const wxString& dir);
@@ -162,7 +162,7 @@ public:
 
 #if wxUSE_LONGLONG
     // returns the size of all directories recursively found in given path
-    static wxULongLong GetTotalSize(const wxString &dir, wxArrayString *filesSkipped = NULL);
+    static wxULongLong GetTotalSize(const wxString &dir, wxArrayString *filesSkipped = nullptr);
 #endif // wxUSE_LONGLONG
 
 

include/wx/dirdlg.h

@@ -136,7 +136,7 @@ wxDirSelector(const wxString& message = wxASCII_STR(wxDirSelectorPromptStr),
               const wxString& defaultPath = wxEmptyString,
               long style = wxDD_DEFAULT_STYLE,
               const wxPoint& pos = wxDefaultPosition,
-              wxWindow *parent = NULL);
+              wxWindow *parent = nullptr);
 
 #endif // wxUSE_DIRDLG
 

include/wx/display.h

@@ -73,7 +73,7 @@ public:
 
 
     // return true if the object was initialized successfully
-    bool IsOk() const { return m_impl != NULL; }
+    bool IsOk() const { return m_impl != nullptr; }
 
     // get the full display size
     wxRect GetGeometry() const;

include/wx/dlist.h

@@ -42,7 +42,7 @@ public:
 
     public:
         compatibility_iterator()
-            : m_iter(), m_list( NULL ) {}
+            : m_iter(), m_list( nullptr ) {}
         compatibility_iterator( ListType* li, iterator i )
             : m_iter( i ), m_list( li ) {}
         compatibility_iterator( const ListType* li, iterator i )
@@ -206,10 +206,10 @@ public:
     class Node
     {
     public:
-        Node(wxDList<T> *list = NULL,
+        Node(wxDList<T> *list = nullptr,
-             Node *previous = NULL,
+             Node *previous = nullptr,
-             Node *next = NULL,
+             Node *next = nullptr,
-             T *data = NULL)
+             T *data = nullptr)
         {
             m_list = list;
             m_previous = previous;
@@ -226,7 +226,7 @@ public:
             // handle the case when we're being deleted from the list by
             // the user (i.e. not by the list itself from DeleteNode) -
             // we must do it for compatibility with old code
-            if (m_list != NULL)
+            if (m_list != nullptr)
                 m_list->DetachNode(this);
         }
 
@@ -267,7 +267,7 @@ public:
     class compatibility_iterator
     {
     public:
-        compatibility_iterator(nodetype *ptr = NULL) : m_ptr(ptr) { }
+        compatibility_iterator(nodetype *ptr = nullptr) : m_ptr(ptr) { }
         nodetype *operator->() const { return m_ptr; }
         operator nodetype *() const  { return m_ptr; }
 
@@ -279,7 +279,7 @@ private:
     void Init()
     {
         m_nodeFirst =
-        m_nodeLast = NULL;
+        m_nodeLast = nullptr;
         m_count = 0;
         m_destroy = false;
     }
@@ -289,7 +289,7 @@ private:
         if ( m_destroy )
             node->DeleteData();
         // so that the node knows that it's being deleted by the list
-        node->m_list = NULL;
+        node->m_list = nullptr;
         delete node;
     }
 
@@ -328,7 +328,7 @@ public:
     ~wxDList()
     {
         nodetype *each = m_nodeFirst;
-        while ( each != NULL )
+        while ( each != nullptr )
         {
             nodetype *next = each->GetNext();
                 DoDeleteNode(each);
@@ -342,8 +342,8 @@ public:
                       "copying list which owns it's elements is a bad idea" );
         Clear();
         m_destroy = list.m_destroy;
-        m_nodeFirst = NULL;
+        m_nodeFirst = nullptr;
-        m_nodeLast = NULL;
+        m_nodeLast = nullptr;
         nodetype* node;
         for (node = list.GetFirst(); node; node = node->GetNext() )
             Append(node->GetData());
@@ -352,7 +352,7 @@ public:
 
     nodetype *Append( T *object )
     {
-        nodetype *node = new nodetype( this, m_nodeLast, NULL, object );
+        nodetype *node = new nodetype( this, m_nodeLast, nullptr, object );
 
         if ( !m_nodeFirst )
         {
@@ -370,7 +370,7 @@ public:
 
     nodetype *Insert( T* object )
     {
-        return Insert( NULL, object );
+        return Insert( nullptr, object );
     }
 
     nodetype *Insert( size_t pos, T* object )
@@ -383,7 +383,7 @@ public:
 
     nodetype *Insert( nodetype *position, T* object )
     {
-        wxCHECK_MSG( !position || position->m_list == this, NULL,
+        wxCHECK_MSG( !position || position->m_list == this, nullptr,
                      "can't insert before a node from another list" );
 
         // previous and next node for the node being inserted
@@ -396,13 +396,13 @@ public:
         else
         {
             // inserting in the beginning of the list
-            prev = NULL;
+            prev = nullptr;
             next = m_nodeFirst;
         }
         nodetype *node = new nodetype( this, prev, next, object );
         if ( !m_nodeFirst )
             m_nodeLast = node;
-        if ( prev == NULL )
+        if ( prev == nullptr )
             m_nodeFirst = node;
         m_count++;
         return node;
@@ -424,19 +424,19 @@ public:
                return current;
         }
         wxFAIL_MSG( "invalid index in Item()" );
-        return NULL;
+        return nullptr;
     }
 
     T *operator[](size_t index) const
     {
         nodetype *node = Item(index);
-        return node ? node->GetData() : NULL;
+        return node ? node->GetData() : nullptr;
     }
 
     nodetype *DetachNode( nodetype *node )
     {
-        wxCHECK_MSG( node, NULL, "detaching NULL wxNodeBase" );
+        wxCHECK_MSG( node, nullptr, "detaching null wxNodeBase" );
-        wxCHECK_MSG( node->m_list == this, NULL,
+        wxCHECK_MSG( node->m_list == this, nullptr,
                      "detaching node which is not from this list" );
         // update the list
         nodetype **prevNext = node->GetPrevious() ? &node->GetPrevious()->m_next
@@ -447,7 +447,7 @@ public:
         *nextPrev = node->GetPrevious();
         m_count--;
         // mark the node as not belonging to this list any more
-        node->m_list = NULL;
+        node->m_list = nullptr;
         return node;
     }
 
@@ -486,7 +486,7 @@ public:
                 return current;
         }
         // not found
-        return NULL;
+        return nullptr;
     }
 
     int IndexOf(const T *object) const
@@ -511,7 +511,7 @@ public:
             current = next;
         }
         m_nodeFirst =
-        m_nodeLast = NULL;
+        m_nodeLast = nullptr;
         m_count = 0;
     }
 
@@ -556,7 +556,7 @@ public:
             if ( (*F)(current->GetData()) )
                 return current->GetData();
         }
-        return NULL;
+        return nullptr;
     }
 
     T *LastThat(wxListIterateFunction F)
@@ -566,7 +566,7 @@ public:
             if ( (*F)(current->GetData()) )
                 return current->GetData();
         }
-        return NULL;
+        return nullptr;
     }
 
     /* STL interface */
@@ -593,7 +593,7 @@ public:
         typedef ptr_type pointer_type;
 
         iterator(Node* node, Node* init) : m_node(node), m_init(init) {}
-        iterator() : m_node(NULL), m_init(NULL) { }
+        iterator() : m_node(nullptr), m_init(nullptr) { }
         reference_type operator*() const
             { return *m_node->GetDataPtr(); }
         // ptrop
@@ -633,7 +633,7 @@ public:
 
         const_iterator(Node* node, Node* init)
             : m_node(node), m_init(init) { }
-        const_iterator() : m_node(NULL), m_init(NULL) { }
+        const_iterator() : m_node(nullptr), m_init(nullptr) { }
         const_iterator(const iterator& it)
             : m_node(it.m_node), m_init(it.m_init) { }
         reference_type operator*() const
@@ -676,7 +676,7 @@ public:
 
         reverse_iterator(Node* node, Node* init)
             : m_node(node), m_init(init) { }
-        reverse_iterator() : m_node(NULL), m_init(NULL) { }
+        reverse_iterator() : m_node(nullptr), m_init(nullptr) { }
         reference_type operator*() const
             { return *m_node->GetDataPtr(); }
         // ptrop
@@ -715,7 +715,7 @@ public:
 
         const_reverse_iterator(Node* node, Node* init)
             : m_node(node), m_init(init) { }
-        const_reverse_iterator() : m_node(NULL), m_init(NULL) { }
+        const_reverse_iterator() : m_node(nullptr), m_init(nullptr) { }
         const_reverse_iterator(const reverse_iterator& it)
             : m_node(it.m_node), m_init(it.m_init) { }
         reference_type operator*() const
@@ -746,15 +746,15 @@ public:
     iterator begin() { return iterator(GetFirst(), GetLast()); }
     const_iterator begin() const
         { return const_iterator(GetFirst(), GetLast()); }
-    iterator end() { return iterator(NULL, GetLast()); }
+    iterator end() { return iterator(nullptr, GetLast()); }
-    const_iterator end() const { return const_iterator(NULL, GetLast()); }
+    const_iterator end() const { return const_iterator(nullptr, GetLast()); }
     reverse_iterator rbegin()
         { return reverse_iterator(GetLast(), GetFirst()); }
     const_reverse_iterator rbegin() const
         { return const_reverse_iterator(GetLast(), GetFirst()); }
-    reverse_iterator rend() { return reverse_iterator(NULL, GetFirst()); }
+    reverse_iterator rend() { return reverse_iterator(nullptr, GetFirst()); }
     const_reverse_iterator rend() const
-        { return const_reverse_iterator(NULL, GetFirst()); }
+        { return const_reverse_iterator(nullptr, GetFirst()); }
     void resize(size_type n, value_type v = value_type())
     {
         while (n < size())

include/wx/dnd.h

@@ -62,7 +62,7 @@ public:
         : m_cursorCopy(cursorCopy),
           m_cursorMove(cursorMove),
           m_cursorStop(cursorStop)
-        { m_data = NULL; }
+        { m_data = nullptr; }
     virtual ~wxDropSourceBase() { }
 
     // set the data which is transferred by drag and drop
@@ -134,7 +134,7 @@ public:
     // ctor takes a pointer to heap-allocated wxDataObject which will be owned
     // by wxDropTarget and deleted by it automatically. If you don't give it
     // here, you can use SetDataObject() later.
-    wxDropTargetBase(wxDataObject *dataObject = NULL)
+    wxDropTargetBase(wxDataObject *dataObject = nullptr)
         { m_dataObject = dataObject; m_defaultAction = wxDragNone; }
     // dtor deletes our data object
     virtual ~wxDropTargetBase()

include/wx/docview.h

@@ -67,7 +67,7 @@ typedef wxVector<wxDocTemplate*> wxDocTemplateVector;
 class WXDLLIMPEXP_CORE wxDocument : public wxEvtHandler
 {
 public:
-    wxDocument(wxDocument *parent = NULL);
+    wxDocument(wxDocument *parent = nullptr);
     virtual ~wxDocument();
 
     // accessors
@@ -159,7 +159,7 @@ public:
 
     wxView *GetFirstView() const;
 
-    virtual void UpdateAllViews(wxView *sender = NULL, wxObject *hint = NULL);
+    virtual void UpdateAllViews(wxView *sender = nullptr, wxObject *hint = nullptr);
     virtual void NotifyClosing();
 
     // Remove all views (because we're closing the document)
@@ -183,7 +183,7 @@ public:
 
     // Returns true if this document is a child document corresponding to a
     // part of the parent document and not a disk file as usual.
-    bool IsChildDocument() const { return m_documentParent != NULL; }
+    bool IsChildDocument() const { return m_documentParent != nullptr; }
 
     // Ask the user if the document should be saved if it's modified and save
     // it if necessary.
@@ -199,7 +199,7 @@ protected:
     wxDocTemplate*        m_documentTemplate;
     bool                  m_documentModified;
 
-    // if the document parent is non-NULL, it's a pseudo-document corresponding
+    // if the document parent is non-null, it's a pseudo-document corresponding
     // to a part of the parent document which can't be saved or loaded
     // independently of its parent and is always closed when its parent is
     wxDocument*           m_documentParent;
@@ -245,7 +245,7 @@ public:
                                 wxView *deactiveView);
     virtual void OnDraw(wxDC *dc) = 0;
     virtual void OnPrint(wxDC *dc, wxObject *info);
-    virtual void OnUpdate(wxView *sender, wxObject *hint = NULL);
+    virtual void OnUpdate(wxView *sender, wxObject *hint = nullptr);
     virtual void OnClosingDocument() {}
     virtual void OnChangeFilename();
 
@@ -280,7 +280,7 @@ public:
     // destroyed
     void SetDocChildFrame(wxDocChildFrameAnyBase *docChildFrame);
 
-    // get the associated frame, may be NULL during destruction
+    // get the associated frame, may be null during destruction
     wxDocChildFrameAnyBase* GetDocChildFrame() const { return m_docChildFrame; }
 
 protected:
@@ -314,8 +314,8 @@ public:
                   const wxString& ext,
                   const wxString& docTypeName,
                   const wxString& viewTypeName,
-                  wxClassInfo *docClassInfo = NULL,
+                  wxClassInfo *docClassInfo = nullptr,
-                  wxClassInfo *viewClassInfo = NULL,
+                  wxClassInfo *viewClassInfo = nullptr,
                   long flags = wxDEFAULT_TEMPLATE_FLAGS);
 
     virtual ~wxDocTemplate();
@@ -446,10 +446,10 @@ public:
     void AssociateTemplate(wxDocTemplate *temp);
     void DisassociateTemplate(wxDocTemplate *temp);
 
-    // Find template from document class info, may return NULL.
+    // Find template from document class info, may return nullptr.
     wxDocTemplate* FindTemplate(const wxClassInfo* documentClassInfo);
 
-    // Find document from file name, may return NULL.
+    // Find document from file name, may return nullptr.
     wxDocument* FindDocumentByPath(const wxString& path) const;
 
     wxDocument *GetCurrentDocument() const;
@@ -476,7 +476,7 @@ public:
     virtual wxView *GetCurrentView() const { return m_currentView; }
 
     // This method tries to find an active view harder than GetCurrentView():
-    // if the latter is NULL, it also checks if we don't have just a single
+    // if the latter is null, it also checks if we don't have just a single
     // view and returns it then.
     wxView *GetAnyUsableView() const;
 
@@ -576,10 +576,10 @@ public:
     // default ctor, use Create() after it
     wxDocChildFrameAnyBase()
     {
-        m_childDocument = NULL;
+        m_childDocument = nullptr;
-        m_childView = NULL;
+        m_childView = nullptr;
-        m_win = NULL;
+        m_win = nullptr;
-        m_lastEvent = NULL;
+        m_lastEvent = nullptr;
     }
 
     // full ctor equivalent to using the default one and Create()
@@ -611,7 +611,7 @@ public:
         // prevent the view from deleting us if we're being deleted directly
         // (and not via Close() + Destroy())
         if ( m_childView )
-            m_childView->SetDocChildFrame(NULL);
+            m_childView->SetDocChildFrame(nullptr);
     }
 
     wxDocument *GetDocument() const { return m_childDocument; }
@@ -808,7 +808,7 @@ public:
     wxDocParentFrameAnyBase(wxWindow* frame)
         : m_frame(frame)
     {
-        m_docManager = NULL;
+        m_docManager = nullptr;
     }
 
     wxDocManager *GetDocumentManager() const { return m_docManager; }
@@ -949,7 +949,7 @@ private:
 class WXDLLIMPEXP_CORE wxDocPrintout : public wxPrintout
 {
 public:
-    wxDocPrintout(wxView *view = NULL, const wxString& title = wxString());
+    wxDocPrintout(wxView *view = nullptr, const wxString& title = wxString());
 
     // implement wxPrintout methods
     virtual bool OnPrintPage(int page) override;

include/wx/dvrenderers.h

@@ -203,7 +203,7 @@ public:
     virtual wxWindow* CreateEditorCtrl(wxWindow * WXUNUSED(parent),
                                        wxRect WXUNUSED(labelRect),
                                        const wxVariant& WXUNUSED(value))
-        { return NULL; }
+        { return nullptr; }
     virtual bool GetValueFromEditorCtrl(wxWindow * WXUNUSED(editor),
                                         wxVariant& WXUNUSED(value))
         { return false; }

include/wx/dynarray.h

@@ -360,7 +360,7 @@ public:
         T* const pItem = Traits::Clone(item);
 
         const size_t nOldSize = size();
-        if ( pItem != NULL )
+        if ( pItem != nullptr )
             base::insert(this->end(), nInsert, pItem);
 
         for ( size_t i = 1; i < nInsert; i++ )
@@ -381,7 +381,7 @@ public:
             return;
 
         T* const pItem = Traits::Clone(item);
-        if ( pItem != NULL )
+        if ( pItem != nullptr )
             base::insert(this->begin() + uiIndex, nInsert, pItem);
 
         for ( size_t i = 1; i < nInsert; ++i )

include/wx/dynlib.h

@@ -62,7 +62,7 @@ enum wxDLFlags
     // and especially don't use directly, use wxLoadedDLL instead if you really
     // do need it
     wxDL_GET_LOADED = 0x00000040,   // Win32 only: return handle of already
-                                    // loaded DLL or NULL otherwise; Unload()
+                                    // loaded DLL or nullptr otherwise; Unload()
                                     // should not be called so don't forget to
                                     // Detach() if you use this function
 
@@ -162,7 +162,7 @@ class WXDLLIMPEXP_BASE wxDynamicLibraryDetails
 public:
     // ctor, normally never used as these objects are only created by
     // wxDynamicLibrary::ListLoaded()
-    wxDynamicLibraryDetails() { m_address = NULL; m_length = 0; }
+    wxDynamicLibraryDetails() { m_address = nullptr; m_length = 0; }
 
     // get the (base) name
     wxString GetName() const { return m_name; }
@@ -213,16 +213,16 @@ WX_DECLARE_USER_EXPORTED_OBJARRAY(wxDynamicLibraryDetails,
 class WXDLLIMPEXP_BASE wxDynamicLibrary
 {
 public:
-    // return a valid handle for the main program itself or NULL if back
+    // return a valid handle for the main program itself or nullptr if back
     // linking is not supported by the current platform (e.g. Win32)
     static wxDllType         GetProgramHandle();
 
     // return the platform standard DLL extension (with leading dot)
     static wxString GetDllExt(wxDynamicLibraryCategory cat = wxDL_LIBRARY);
 
-    wxDynamicLibrary() : m_handle(NULL) { }
+    wxDynamicLibrary() : m_handle(nullptr) { }
     wxDynamicLibrary(const wxString& libname, int flags = wxDL_DEFAULT)
-        : m_handle(NULL)
+        : m_handle(nullptr)
     {
         Load(libname, flags);
     }
@@ -232,14 +232,14 @@ public:
     ~wxDynamicLibrary() { Unload(); }
 
     // return true if the library was loaded successfully
-    bool IsLoaded() const { return m_handle != NULL; }
+    bool IsLoaded() const { return m_handle != nullptr; }
 
     // load the library with the given name (full or not), return true if ok
     bool Load(const wxString& libname, int flags = wxDL_DEFAULT);
 
     // raw function for loading dynamic libs: always behaves as if
     // wxDL_VERBATIM were specified and doesn't log error message if the
-    // library couldn't be loaded but simply returns NULL
+    // library couldn't be loaded but simply returns nullptr
     static wxDllType RawLoad(const wxString& libname, int flags = wxDL_DEFAULT);
 
     // attach to an existing handle
@@ -248,13 +248,13 @@ public:
     // detach the library object from its handle, i.e. prevent the object from
     // unloading the library in its dtor -- the caller is now responsible for
     // doing this
-    wxDllType Detach() { wxDllType h = m_handle; m_handle = NULL; return h; }
+    wxDllType Detach() { wxDllType h = m_handle; m_handle = nullptr; return h; }
 
     // unload the given library handle (presumably returned by Detach() before)
     static void Unload(wxDllType handle);
 
     // unload the library, also done automatically in dtor
-    void Unload() { if ( IsLoaded() ) { Unload(m_handle); m_handle = NULL; } }
+    void Unload() { if ( IsLoaded() ) { Unload(m_handle); m_handle = nullptr; } }
 
     // Return the raw handle from dlopen and friends.
     wxDllType GetLibHandle() const { return m_handle; }
@@ -273,14 +273,14 @@ public:
     // 'name' is the (possibly mangled) name of the symbol. (use extern "C" to
     // export unmangled names)
     //
-    // Since it is perfectly valid for the returned symbol to actually be NULL,
+    // Since it is perfectly valid for the returned symbol to actually be null,
     // that is not always indication of an error.  Pass and test the parameter
     // 'success' for a true indication of success or failure to load the
     // symbol.
     //
-    // Returns a pointer to the symbol on success, or NULL if an error occurred
+    // Returns a pointer to the symbol on success, or nullptr if an error occurred
     // or the symbol wasn't found.
-    void *GetSymbol(const wxString& name, bool *success = NULL) const;
+    void *GetSymbol(const wxString& name, bool *success = nullptr) const;
 
     // low-level version of GetSymbol()
     static void *RawGetSymbol(wxDllType handle, const wxString& name);
@@ -334,11 +334,11 @@ public:
     static wxString GetPluginsDirectory();
 
     // Return the load address of the module containing the given address or
-    // NULL if not found.
+    // nullptr if not found.
     //
-    // If path output parameter is non-NULL, fill it with the full path to this
+    // If path output parameter is non-null, fill it with the full path to this
     // module disk file on success.
-    static void* GetModuleFromAddress(const void* addr, wxString* path = NULL);
+    static void* GetModuleFromAddress(const void* addr, wxString* path = nullptr);
 
 #ifdef __WINDOWS__
     // return the handle (HMODULE/HINSTANCE) of the DLL with the given name
@@ -355,13 +355,13 @@ public:
 
 protected:
     // common part of GetSymbol() and HasSymbol()
-    void* DoGetSymbol(const wxString& name, bool* success = NULL) const;
+    void* DoGetSymbol(const wxString& name, bool* success = nullptr) const;
 
     // log the error after an OS dynamic library function failure
     static void ReportError(const wxString& msg,
                             const wxString& name = wxString());
 
-    // the handle to DLL or NULL
+    // the handle to DLL or nullptr
     wxDllType m_handle;
 
     // no copy ctor/assignment operators (or we'd try to unload the library

include/wx/dynload.h

@@ -81,7 +81,7 @@ public:
 
 private:
 
-    // These pointers may be NULL but if they are not, then m_ourLast follows
+    // These pointers may be null but if they are not, then m_ourLast follows
     // m_ourFirst in the linked list, i.e. can be found by calling GetNext() a
     // sufficient number of times.
     const wxClassInfo    *m_ourFirst; // first class info in this plugin
@@ -112,7 +112,7 @@ public:
 
         // Instance methods.
 
-    wxPluginManager() : m_entry(NULL) {}
+    wxPluginManager() : m_entry(nullptr) {}
     wxPluginManager(const wxString &libname, int flags = wxDL_DEFAULT)
     {
         Load(libname, flags);
@@ -123,22 +123,22 @@ public:
     void   Unload();
 
     bool   IsLoaded() const { return m_entry && m_entry->IsLoaded(); }
-    void* GetSymbol(const wxString& symbol, bool* success = NULL)
+    void* GetSymbol(const wxString& symbol, bool* success = nullptr)
     {
         return m_entry->GetSymbol( symbol, success );
     }
 
     static void CreateManifest() { ms_manifest = new wxDLManifest(wxKEY_STRING); }
-    static void ClearManifest() { delete ms_manifest; ms_manifest = NULL; }
+    static void ClearManifest() { delete ms_manifest; ms_manifest = nullptr; }
 
 private:
     // return the pointer to the entry for the library with given name in
-    // ms_manifest or NULL if none
+    // ms_manifest or nullptr if none
     static wxPluginLibrary *FindByName(const wxString& name)
     {
         const wxDLManifest::iterator i = ms_manifest->find(name);
 
-        return i == ms_manifest->end() ? NULL : i->second;
+        return i == ms_manifest->end() ? nullptr : i->second;
     }
 
     static wxDLManifest* ms_manifest;  // Static hash of loaded libs.

include/wx/editlbox.h

@@ -74,8 +74,8 @@ protected:
     {
         m_style = 0;
         m_selection = 0;
-        m_bEdit = m_bNew = m_bDel = m_bUp = m_bDown = NULL;
+        m_bEdit = m_bNew = m_bDel = m_bUp = m_bDown = nullptr;
-        m_listCtrl = NULL;
+        m_listCtrl = nullptr;
     }
 
     void OnItemSelected(wxListEvent& event);

include/wx/event.h

@@ -87,7 +87,7 @@ typedef int wxEventType;
     wxEventTableEntry(type, winid, idLast, wxNewEventTableFunctor(type, fn), obj)
 
 #define wxDECLARE_EVENT_TABLE_TERMINATOR() \
-    wxEventTableEntry(wxEVT_NULL, 0, 0, NULL, NULL)
+    wxEventTableEntry(wxEVT_NULL, 0, 0, nullptr, nullptr)
 
 // generate a new unique event type
 extern WXDLLIMPEXP_BASE wxEventType wxNewEventType();
@@ -241,14 +241,14 @@ public:
     // If the functor holds an wxEvtHandler, then get access to it and track
     // its lifetime with wxEventConnectionRef:
     virtual wxEvtHandler *GetEvtHandler() const
-        { return NULL; }
+        { return nullptr; }
 
     // This is only used to maintain backward compatibility in
     // wxAppConsoleBase::CallEventHandler and ensures that an overwritten
     // wxAppConsoleBase::HandleEvent is still called for functors which hold an
     // wxEventFunction:
     virtual wxEventFunction GetEvtMethod() const
-        { return NULL; }
+        { return nullptr; }
 
 private:
     WX_DECLARE_ABSTRACT_TYPEINFO(wxEventFunctor)
@@ -289,7 +289,7 @@ private:
     wxEventFunction m_method;
 
     // Provide a dummy default ctor for type info purposes
-    wxObjectEventFunctor() : m_handler(NULL), m_method(NULL) { }
+    wxObjectEventFunctor() : m_handler(nullptr), m_method(nullptr) { }
 
     WX_DECLARE_TYPEINFO_INLINE(wxObjectEventFunctor)
 };
@@ -308,7 +308,7 @@ inline wxObjectEventFunctor *
 wxNewEventTableFunctor(const wxEventType& WXUNUSED(evtType),
                        wxObjectEventFunction method)
 {
-    return new wxObjectEventFunctor(method, NULL);
+    return new wxObjectEventFunctor(method, nullptr);
 }
 
 inline wxObjectEventFunctor
@@ -369,11 +369,11 @@ struct HandlerImpl<T, A, false>
     static bool IsEvtHandler()
         { return false; }
     static T *ConvertFromEvtHandler(wxEvtHandler *)
-        { return NULL; }
+        { return nullptr; }
     static wxEvtHandler *ConvertToEvtHandler(T *)
-        { return NULL; }
+        { return nullptr; }
     static wxEventFunction ConvertToEvtMethod(void (T::*)(A&))
-        { return NULL; }
+        { return nullptr; }
 };
 
 } // namespace wxPrivate
@@ -416,7 +416,7 @@ public:
         // if you get an error here it means that the signature of the handler
         // you're trying to use is not compatible with (i.e. is not the same as
         // or a base class of) the real event class used for this event type
-        CheckHandlerArgument(static_cast<EventClass *>(NULL));
+        CheckHandlerArgument(static_cast<EventClass *>(nullptr));
     }
 
     virtual void operator()(wxEvtHandler *handler, wxEvent& event) override
@@ -447,8 +447,8 @@ public:
         // the cast is valid because wxTypeId()s matched above
         const ThisFunctor& other = static_cast<const ThisFunctor &>(functor);
 
-        return (m_method == other.m_method || other.m_method == NULL) &&
+        return (m_method == other.m_method || other.m_method == nullptr) &&
-               (m_handler == other.m_handler || other.m_handler == NULL);
+               (m_handler == other.m_handler || other.m_handler == nullptr);
     }
 
     virtual wxEvtHandler *GetEvtHandler() const override
@@ -487,7 +487,7 @@ public:
         // if you get an error here it means that the signature of the handler
         // you're trying to use is not compatible with (i.e. is not the same as
         // or a base class of) the real event class used for this event type
-        CheckHandlerArgument(static_cast<EventClass *>(NULL));
+        CheckHandlerArgument(static_cast<EventClass *>(nullptr));
     }
 
     virtual void operator()(wxEvtHandler *WXUNUSED(handler), wxEvent& event) override
@@ -495,10 +495,10 @@ public:
         // If you get an error here like "must use .* or ->* to call
         // pointer-to-member function" then you probably tried to call
         // Bind/Unbind with a method pointer but without a handler pointer or
-        // NULL as a handler e.g.:
+        // nullptr as a handler e.g.:
         // Unbind( wxEVT_XXX, &EventHandler::method );
         // or
-        // Unbind( wxEVT_XXX, &EventHandler::method, NULL )
+        // Unbind( wxEVT_XXX, &EventHandler::method, nullptr )
         m_handler(static_cast<EventArg&>(event));
     }
 
@@ -540,10 +540,10 @@ public:
         // If you get an error here like "must use '.*' or '->*' to call
         // pointer-to-member function" then you probably tried to call
         // Bind/Unbind with a method pointer but without a handler pointer or
-        // NULL as a handler e.g.:
+        // nullptr as a handler e.g.:
         // Unbind( wxEVT_XXX, &EventHandler::method );
         // or
-        // Unbind( wxEVT_XXX, &EventHandler::method, NULL )
+        // Unbind( wxEVT_XXX, &EventHandler::method, nullptr )
         m_handler(static_cast<EventArg&>(event));
     }
 
@@ -643,7 +643,7 @@ inline wxEventFunctorMethod<EventTag, Class, EventArg, Class> *
 wxNewEventTableFunctor(const EventTag&, void (Class::*method)(EventArg&))
 {
     return new wxEventFunctorMethod<EventTag, Class, EventArg, Class>(
-                    method, NULL);
+                    method, nullptr);
 }
 
 
@@ -1085,7 +1085,7 @@ public:
     // never be used anywhere else.
     void DidntHonourProcessOnlyIn()
     {
-        m_handlerToProcessOnlyIn = NULL;
+        m_handlerToProcessOnlyIn = nullptr;
     }
 
 protected:
@@ -1107,7 +1107,7 @@ protected:
     // the parent window (if any)
     int               m_propagationLevel;
 
-    // The object that the event is being propagated from, initially NULL and
+    // The object that the event is being propagated from, initially nullptr and
     // only set by wxPropagateOnce.
     wxEvtHandler*     m_propagatedFrom;
 
@@ -1170,10 +1170,10 @@ private:
 class WXDLLIMPEXP_BASE wxPropagateOnce
 {
 public:
-    // The handler argument should normally be non-NULL to allow the parent
+    // The handler argument should normally be non-null to allow the parent
     // event handler to know that it's being used to process an event coming
-    // from the child, it's only NULL by default for backwards compatibility.
+    // from the child, it's only nullptr by default for backwards compatibility.
-    wxPropagateOnce(wxEvent& event, wxEvtHandler* handler = NULL)
+    wxPropagateOnce(wxEvent& event, wxEvtHandler* handler = nullptr)
         : m_event(event),
           m_propagatedFromOld(event.m_propagatedFrom)
     {
@@ -1607,8 +1607,8 @@ public:
     wxCommandEvent(wxEventType commandType = wxEVT_NULL, int winid = 0)
         : wxEvent(winid, commandType)
     {
-        m_clientData = NULL;
+        m_clientData = nullptr;
-        m_clientObject = NULL;
+        m_clientObject = nullptr;
         m_isCommandEvent = true;
 
         // the command events are propagated upwards by default
@@ -2420,7 +2420,7 @@ class WXDLLIMPEXP_CORE wxPaintEvent : public wxEvent
 #ifdef WXBUILDING
 public:
 #endif // WXBUILDING
-    explicit wxPaintEvent(wxWindowBase* window = NULL);
+    explicit wxPaintEvent(wxWindowBase* window = nullptr);
 
 public:
     // default copy ctor and dtor are fine
@@ -2438,7 +2438,7 @@ class WXDLLIMPEXP_CORE wxNcPaintEvent : public wxEvent
 #ifdef WXBUILDING
 public:
 #endif // WXBUILDING
-    explicit wxNcPaintEvent(wxWindowBase* window = NULL);
+    explicit wxNcPaintEvent(wxWindowBase* window = nullptr);
 
 public:
     virtual wxEvent *Clone() const override { return new wxNcPaintEvent(*this); }
@@ -2455,7 +2455,7 @@ private:
 class WXDLLIMPEXP_CORE wxEraseEvent : public wxEvent
 {
 public:
-    wxEraseEvent(int Id = 0, wxDC *dc = NULL)
+    wxEraseEvent(int Id = 0, wxDC *dc = nullptr)
         : wxEvent(Id, wxEVT_ERASE_BACKGROUND),
           m_dc(dc)
         { }
@@ -2487,7 +2487,7 @@ class WXDLLIMPEXP_CORE wxFocusEvent : public wxEvent
 public:
     wxFocusEvent(wxEventType type = wxEVT_NULL, int winid = 0)
         : wxEvent(winid, type)
-        { m_win = NULL; }
+        { m_win = nullptr; }
 
     wxFocusEvent(const wxFocusEvent& event)
         : wxEvent(event)
@@ -2495,7 +2495,7 @@ public:
 
     // The window associated with this event is the window which had focus
     // before for SET event and the window which will have focus for the KILL
-    // one. NB: it may be NULL in both cases!
+    // one. NB: it may be null in both cases!
     wxWindow *GetWindow() const { return m_win; }
     void SetWindow(wxWindow *win) { m_win = win; }
 
@@ -2513,7 +2513,7 @@ private:
 class WXDLLIMPEXP_CORE wxChildFocusEvent : public wxCommandEvent
 {
 public:
-    wxChildFocusEvent(wxWindow *win = NULL);
+    wxChildFocusEvent(wxWindow *win = nullptr);
 
     wxWindow *GetWindow() const { return (wxWindow *)GetEventObject(); }
 
@@ -2596,7 +2596,7 @@ private:
 class WXDLLIMPEXP_CORE wxMenuEvent : public wxEvent
 {
 public:
-    wxMenuEvent(wxEventType type = wxEVT_NULL, int winid = 0, wxMenu* menu = NULL)
+    wxMenuEvent(wxEventType type = wxEVT_NULL, int winid = 0, wxMenu* menu = nullptr)
         : wxEvent(winid, type)
         { m_menuId = winid; m_menu = menu; }
     wxMenuEvent(const wxMenuEvent& event)
@@ -2885,7 +2885,7 @@ public:
 
     wxDropFilesEvent(wxEventType type = wxEVT_NULL,
                      int noFiles = 0,
-                     wxString *files = NULL)
+                     wxString *files = nullptr)
         : wxEvent(0, type),
           m_noFiles(noFiles),
           m_pos(),
@@ -2897,7 +2897,7 @@ public:
         : wxEvent(other),
           m_noFiles(other.m_noFiles),
           m_pos(other.m_pos),
-          m_files(NULL)
+          m_files(nullptr)
     {
         m_files = new wxString[m_noFiles];
         for ( int n = 0; n < m_noFiles; n++ )
@@ -3057,7 +3057,7 @@ private:
 class WXDLLIMPEXP_CORE wxMouseCaptureChangedEvent : public wxEvent
 {
 public:
-    wxMouseCaptureChangedEvent(wxWindowID winid = 0, wxWindow* gainedCapture = NULL)
+    wxMouseCaptureChangedEvent(wxWindowID winid = 0, wxWindow* gainedCapture = nullptr)
         : wxEvent(winid, wxEVT_MOUSE_CAPTURE_CHANGED),
           m_gainedCapture(gainedCapture)
         { }
@@ -3158,7 +3158,7 @@ class WXDLLIMPEXP_CORE wxPaletteChangedEvent : public wxEvent
 public:
     wxPaletteChangedEvent(wxWindowID winid = 0)
         : wxEvent(winid, wxEVT_PALETTE_CHANGED),
-          m_changedWindow(NULL)
+          m_changedWindow(nullptr)
         { }
 
     wxPaletteChangedEvent(const wxPaletteChangedEvent& event)
@@ -3219,7 +3219,7 @@ public:
     wxNavigationKeyEvent()
         : wxEvent(0, wxEVT_NAVIGATION_KEY),
           m_flags(IsForward | FromTab),    // defaults are for TAB
-          m_focus(NULL)
+          m_focus(nullptr)
         {
             m_propagationLevel = wxEVENT_PROPAGATE_NONE;
         }
@@ -3250,7 +3250,7 @@ public:
     void SetFromTab(bool bIs)
         { if ( bIs ) m_flags |= FromTab; else m_flags &= ~FromTab; }
 
-    // the child which has the focus currently (may be NULL - use
+    // the child which has the focus currently (may be null - use
     // wxWindow::FindFocus then)
     wxWindow* GetCurrentFocus() const { return m_focus; }
     void SetCurrentFocus(wxWindow *win) { m_focus = win; }
@@ -3288,7 +3288,7 @@ private:
 class WXDLLIMPEXP_CORE wxWindowCreateEvent : public wxCommandEvent
 {
 public:
-    wxWindowCreateEvent(wxWindow *win = NULL);
+    wxWindowCreateEvent(wxWindow *win = nullptr);
 
     wxWindow *GetWindow() const { return (wxWindow *)GetEventObject(); }
 
@@ -3301,7 +3301,7 @@ private:
 class WXDLLIMPEXP_CORE wxWindowDestroyEvent : public wxCommandEvent
 {
 public:
-    wxWindowDestroyEvent(wxWindow *win = NULL);
+    wxWindowDestroyEvent(wxWindow *win = nullptr);
 
     wxWindow *GetWindow() const { return (wxWindow *)GetEventObject(); }
 
@@ -3484,7 +3484,7 @@ struct WXDLLIMPEXP_BASE wxEventTableEntryBase
         // being initialized (a temporary instance is created and then this
         // constructor is called).
 
-        const_cast<wxEventTableEntryBase&>( entry ).m_fn = NULL;
+        const_cast<wxEventTableEntryBase&>( entry ).m_fn = nullptr;
     }
 
     ~wxEventTableEntryBase()
@@ -3795,8 +3795,8 @@ public:
                  int lastId,
                  wxEventType eventType,
                  wxObjectEventFunction func,
-                 wxObject *userData = NULL,
+                 wxObject *userData = nullptr,
-                 wxEvtHandler *eventSink = NULL)
+                 wxEvtHandler *eventSink = nullptr)
     {
         DoBind(winid, lastId, eventType,
                   wxNewEventFunctor(eventType, func, eventSink),
@@ -3807,23 +3807,23 @@ public:
     void Connect(int winid,
                  wxEventType eventType,
                  wxObjectEventFunction func,
-                 wxObject *userData = NULL,
+                 wxObject *userData = nullptr,
-                 wxEvtHandler *eventSink = NULL)
+                 wxEvtHandler *eventSink = nullptr)
         { Connect(winid, wxID_ANY, eventType, func, userData, eventSink); }
 
     // Even more convenient: without id (same as using id of wxID_ANY)
     void Connect(wxEventType eventType,
                  wxObjectEventFunction func,
-                 wxObject *userData = NULL,
+                 wxObject *userData = nullptr,
-                 wxEvtHandler *eventSink = NULL)
+                 wxEvtHandler *eventSink = nullptr)
         { Connect(wxID_ANY, wxID_ANY, eventType, func, userData, eventSink); }
 
     bool Disconnect(int winid,
                     int lastId,
                     wxEventType eventType,
-                    wxObjectEventFunction func = NULL,
+                    wxObjectEventFunction func = nullptr,
-                    wxObject *userData = NULL,
+                    wxObject *userData = nullptr,
-                    wxEvtHandler *eventSink = NULL)
+                    wxEvtHandler *eventSink = nullptr)
     {
         return DoUnbind(winid, lastId, eventType,
                             wxMakeEventFunctor(eventType, func, eventSink),
@@ -3832,15 +3832,15 @@ public:
 
     bool Disconnect(int winid = wxID_ANY,
                     wxEventType eventType = wxEVT_NULL,
-                    wxObjectEventFunction func = NULL,
+                    wxObjectEventFunction func = nullptr,
-                    wxObject *userData = NULL,
+                    wxObject *userData = nullptr,
-                    wxEvtHandler *eventSink = NULL)
+                    wxEvtHandler *eventSink = nullptr)
         { return Disconnect(winid, wxID_ANY, eventType, func, userData, eventSink); }
 
     bool Disconnect(wxEventType eventType,
                     wxObjectEventFunction func,
-                    wxObject *userData = NULL,
+                    wxObject *userData = nullptr,
-                    wxEvtHandler *eventSink = NULL)
+                    wxEvtHandler *eventSink = nullptr)
         { return Disconnect(wxID_ANY, eventType, func, userData, eventSink); }
 
     // Bind functions to an event:
@@ -3849,7 +3849,7 @@ public:
               void (*function)(EventArg &),
               int winid = wxID_ANY,
               int lastId = wxID_ANY,
-              wxObject *userData = NULL)
+              wxObject *userData = nullptr)
     {
         DoBind(winid, lastId, eventType,
                   wxNewEventFunctor(eventType, function),
@@ -3862,7 +3862,7 @@ public:
                 void (*function)(EventArg &),
                 int winid = wxID_ANY,
                 int lastId = wxID_ANY,
-                wxObject *userData = NULL)
+                wxObject *userData = nullptr)
     {
         return DoUnbind(winid, lastId, eventType,
                             wxMakeEventFunctor(eventType, function),
@@ -3875,7 +3875,7 @@ public:
               const Functor &functor,
               int winid = wxID_ANY,
               int lastId = wxID_ANY,
-              wxObject *userData = NULL)
+              wxObject *userData = nullptr)
     {
         DoBind(winid, lastId, eventType,
                   wxNewEventFunctor(eventType, functor),
@@ -3888,7 +3888,7 @@ public:
                 const Functor &functor,
                 int winid = wxID_ANY,
                 int lastId = wxID_ANY,
-                wxObject *userData = NULL)
+                wxObject *userData = nullptr)
     {
         return DoUnbind(winid, lastId, eventType,
                             wxMakeEventFunctor(eventType, functor),
@@ -3905,7 +3905,7 @@ public:
               EventHandler *handler,
               int winid = wxID_ANY,
               int lastId = wxID_ANY,
-              wxObject *userData = NULL)
+              wxObject *userData = nullptr)
     {
         DoBind(winid, lastId, eventType,
                   wxNewEventFunctor(eventType, method, handler),
@@ -3918,7 +3918,7 @@ public:
                 EventHandler *handler,
                 int winid = wxID_ANY,
                 int lastId = wxID_ANY,
-                wxObject *userData = NULL )
+                wxObject *userData = nullptr )
     {
         return DoUnbind(winid, lastId, eventType,
                             wxMakeEventFunctor(eventType, method, handler),
@@ -3967,13 +3967,13 @@ private:
                    int lastId,
                    wxEventType eventType,
                    wxEventFunctor *func,
-                   wxObject* userData = NULL);
+                   wxObject* userData = nullptr);
 
     bool DoUnbind(int winid,
                       int lastId,
                       wxEventType eventType,
                       const wxEventFunctor& func,
-                      wxObject *userData = NULL);
+                      wxObject *userData = nullptr);
 
     static const wxEventTableEntry sm_eventTableEntries[];
 
@@ -4099,7 +4099,7 @@ inline void wxObjectEventFunctor::operator()(wxEvtHandler *handler, wxEvent& eve
 class wxEventConnectionRef : public wxTrackerNode
 {
 public:
-    wxEventConnectionRef() : m_src(NULL), m_sink(NULL), m_refCount(0) { }
+    wxEventConnectionRef() : m_src(nullptr), m_sink(nullptr), m_refCount(0) { }
     wxEventConnectionRef(wxEvtHandler *src, wxEvtHandler *sink)
         : m_src(src), m_sink(sink), m_refCount(1)
     {
@@ -4474,7 +4474,7 @@ typedef void (wxEvtHandler::*wxPressAndTapEventFunction)(wxPressAndTapEvent&);
 //  - id1, id2 ids of the first/last id
 //  - fn the function (should be cast to the right type)
 #define wx__DECLARE_EVT2(evt, id1, id2, fn) \
-    wxDECLARE_EVENT_TABLE_ENTRY(evt, id1, id2, fn, NULL),
+    wxDECLARE_EVENT_TABLE_ENTRY(evt, id1, id2, fn, nullptr),
 #define wx__DECLARE_EVT1(evt, id, fn) \
     wx__DECLARE_EVT2(evt, id, wxID_ANY, fn)
 #define wx__DECLARE_EVT0(evt, fn) \

include/wx/eventfilter.h

@@ -40,7 +40,7 @@ public:
 
     wxEventFilter()
     {
-        m_next = NULL;
+        m_next = nullptr;
     }
 
     virtual ~wxEventFilter()

include/wx/evtloop.h

@@ -174,7 +174,7 @@ public:
     // active loop
     // -----------
 
-    // return currently active (running) event loop, may be NULL
+    // return currently active (running) event loop, may be null
     static wxEventLoopBase *GetActive() { return ms_activeLoop; }
 
     // set currently active (running) event loop
@@ -307,7 +307,7 @@ class WXDLLIMPEXP_FWD_CORE wxEventLoopImpl;
 class WXDLLIMPEXP_CORE wxGUIEventLoop : public wxEventLoopBase
 {
 public:
-    wxGUIEventLoop() { m_impl = NULL; }
+    wxGUIEventLoop() { m_impl = nullptr; }
     virtual ~wxGUIEventLoop();
 
     virtual void ScheduleExit(int rc = 0);
@@ -380,7 +380,7 @@ protected:
     virtual void OnExit() override
     {
         delete m_windowDisabler;
-        m_windowDisabler = NULL;
+        m_windowDisabler = nullptr;
 
         wxGUIEventLoop::OnExit();
     }
@@ -424,7 +424,7 @@ class wxEventLoopGuarantor
 public:
     wxEventLoopGuarantor()
     {
-        m_evtLoopNew = NULL;
+        m_evtLoopNew = nullptr;
         if (!wxEventLoop::GetActive())
         {
             m_evtLoopNew = new wxEventLoop;
@@ -436,7 +436,7 @@ public:
     {
         if (m_evtLoopNew)
         {
-            wxEventLoop::SetActive(NULL);
+            wxEventLoop::SetActive(nullptr);
             delete m_evtLoopNew;
         }
     }

include/wx/fdrepdlg.h

@@ -96,7 +96,7 @@ class WXDLLIMPEXP_CORE wxFindReplaceDialogBase : public wxDialog
 {
 public:
     // ctors and such
-    wxFindReplaceDialogBase() { m_FindReplaceData = NULL; }
+    wxFindReplaceDialogBase() { m_FindReplaceData = nullptr; }
     wxFindReplaceDialogBase(wxWindow * WXUNUSED(parent),
                             wxFindReplaceData *data,
                             const wxString& WXUNUSED(title),

include/wx/ffile.h

@@ -34,7 +34,7 @@ public:
   // ctors
   // -----
     // def ctor
-  wxFFile() { m_fp = NULL; }
+  wxFFile() { m_fp = nullptr; }
     // open specified file (may fail, use IsOpened())
   wxFFile(const wxString& filename, const wxString& mode = wxT("r"));
     // attach to (already opened) file
@@ -49,7 +49,7 @@ public:
   // assign an existing file descriptor and get it back from wxFFile object
   void Attach(FILE *lfp, const wxString& name = wxEmptyString)
     { Close(); m_fp = lfp; m_name = name; }
-  FILE* Detach() { FILE* fpOld = m_fp; m_fp = NULL; return fpOld; }
+  FILE* Detach() { FILE* fpOld = m_fp; m_fp = nullptr; return fpOld; }
   FILE *fp() const { return m_fp; }
 
   // read/write (unbuffered)
@@ -78,7 +78,7 @@ public:
   // simple accessors: note that Eof() and Error() may only be called if
   // IsOpened(). Otherwise they assert and return false.
     // is file opened?
-  bool IsOpened() const { return m_fp != NULL; }
+  bool IsOpened() const { return m_fp != nullptr; }
     // is end of file reached?
   bool Eof() const;
     // has an error occurred?
@@ -98,7 +98,7 @@ private:
   wxFFile(const wxFFile&);
   wxFFile& operator=(const wxFFile&);
 
-  FILE *m_fp;       // IO stream or NULL if not opened
+  FILE *m_fp;       // IO stream or nullptr if not opened
 
   wxString m_name;  // the name of the file (for diagnostic messages)
 };

include/wx/fileconf.h

@@ -189,7 +189,7 @@ public:
   // functions to work with this list
   wxFileConfigLineList *LineListAppend(const wxString& str);
   wxFileConfigLineList *LineListInsert(const wxString& str,
-                           wxFileConfigLineList *pLine);    // NULL => Prepend()
+                           wxFileConfigLineList *pLine);    // nullptr => Prepend()
   void      LineListRemove(wxFileConfigLineList *pLine);
   bool      LineListIsEmpty();