Add a simple wxStack<> template class based on wxVector<>.

This is still simpler than std::stack<> which can be used with any container
and not just wxVector<> but better than the WX_DECLARE_STACK() macro which was
all that we had before.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@67047 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/stack.h

@@ -0,0 +1,75 @@
+/////////////////////////////////////////////////////////////////////////////
+// Name:        wx/stack.h
+// Purpose:     interface of wxStack<T>
+// Author:      Vadim Zeitlin
+// RCS-ID:      $Id$
+// Copyright:   (c) 2011 Vadim Zeitlin <vadim@wxwidgets.org>
+// Licence:     wxWindows licence
+/////////////////////////////////////////////////////////////////////////////
+
+/**
+    wxStack<T> is similar to @c std::stack and can be used exactly like it.
+
+    If wxWidgets is compiled in STL mode, wxStack will just be a typedef to
+    @c std::stack but the advantage of this class is that it is also available
+    on the (rare) platforms where STL is not, so using it makes the code
+    marginally more portable. If you only target the standard desktop
+    platforms, please always use @c std::stack directly instead.
+
+    The main difference of this class compared to the standard version is that
+    it always uses wxVector<T> as the underlying container and doesn't allow
+    specifying an alternative container type. Another missing part is that the
+    comparison operators between wxStacks are not currently implemented. Other
+    than that, this class is exactly the same as @c std::stack, so please refer
+    to the STL documentation for further information.
+
+    @nolibrary
+    @category{containers}
+
+    @see @ref overview_container, wxVector<T>
+
+    @since 2.9.2
+*/
+template <typename T>
+class wxSort<T>
+{
+public:
+    /// Type of the underlying container used.
+    typedef wxVector<T> container_type;
+
+    /// Type returned by size() method.
+    typedef typename container_type::size_type size_type;
+
+    /// Type of the elements stored in the stack.
+    typedef typename container_type::value_type value_type;
+
+
+    /**
+        Stack can be created either empty or initialized with the contents of
+        an existing compatible container.
+     */
+    //@{
+    wxStack();
+    explicit wxStack(const container_type& cont);
+    //@}
+
+    /// Return whether the stack is currently empty.
+    bool empty() const;
+
+    /// Return the number of elements in the stack.
+    size_type size() const;
+
+    /**
+        Return the element on top of the stack.
+     */
+    //@{
+    value_type& top();
+    const value_type& top();
+    //@}
+
+    /// Adds an element to the stack.
+    void push(const value_type& val);
+
+    /// Removes the element currently on top of the stack.
+    void pop();
+};