+ virtual void put(std::string const & lyx, docstring const & text) = 0;
+
+ /// Does the clipboard contain LyX contents?
+ virtual bool hasLyXContents() const = 0;
+ /// state of clipboard.
+ /// \returns true if the system clipboard has been set within LyX
+ /// (document contents, dialogs count as external here).
+ virtual bool isInternal() const = 0;
+ /// Is the clipboard empty?
+ /// \returns true if both the LyX and the plaintext versions of the
+ /// clipboard are empty.
+ virtual bool empty() const = 0;