gtk:window-destroy-with-parent (object)

object -- a gtk:window widget
setting -- a boolean whether to destroy the window with its transient parent

The accessor for the destroy-with-parent slot gets or sets whether the window will be destroyed with its transient parent.

If the setting argument is true, then destroying the transient parent of the window will also destroy the window itself. This is useful for dialogs that should not persist beyond the lifetime of the main window they are associated with.