Add wx headers and ext

wxheaders/wx/meta/movable.h

@@ -0,0 +1,44 @@
+/////////////////////////////////////////////////////////////////////////////
+// Name:        wx/meta/movable.h
+// Purpose:     Test if a type is movable using memmove() etc.
+// Author:      Vaclav Slavik
+// Created:     2008-01-21
+// Copyright:   (c) 2008 Vaclav Slavik
+// Licence:     wxWindows licence
+/////////////////////////////////////////////////////////////////////////////
+
+#ifndef _WX_META_MOVABLE_H_
+#define _WX_META_MOVABLE_H_
+
+#include "wx/meta/pod.h"
+#include "wx/string.h" // for wxIsMovable<wxString> specialization
+
+// Helper to decide if an object of type T is "movable", i.e. if it can be
+// copied to another memory location using memmove() or realloc() C functions.
+// C++ only guarantees that POD types (including primitive types) are
+// movable.
+template<typename T>
+struct wxIsMovable
+{
+    static const bool value = wxIsPod<T>::value;
+};
+
+// Macro to add wxIsMovable<T> specialization for given type that marks it
+// as movable:
+#define WX_DECLARE_TYPE_MOVABLE(type)                       \
+    template<> struct wxIsMovable<type>                     \
+    {                                                       \
+        static const bool value = true;                     \
+    };
+
+// Our implementation of wxString is written in such way that it's safe to move
+// it around (unless position cache is used which unfortunately breaks this).
+// OTOH, we don't know anything about std::string.
+// (NB: we don't put this into string.h and choose to include wx/string.h from
+// here instead so that rarely-used wxIsMovable<T> code isn't included by
+// everything)
+#if !wxUSE_STD_STRING && !wxUSE_STRING_POS_CACHE
+WX_DECLARE_TYPE_MOVABLE(wxString)
+#endif
+
+#endif // _WX_META_MOVABLE_H_