onDeleteRange  
  fun onDeleteRange(connectFlags: <Error class: unknown class> = ConnectFlags(0u), handler: (start: TextIter, end: TextIter) -> Unit): <Error class: unknown class>(source)
Emitted to delete a range from a GtkTextBuffer.
Note that if your handler runs before the default handler it must not invalidate the @start and @end iters (or has to revalidate them). The default signal handler revalidates the @start and @end iters to both point to the location where text was deleted. Handlers which run after the default handler (see g_signal_connect_after()) do not have access to the deleted text.
See also: method@Gtk.TextBuffer.delete.
Parameters
connectFlags 
a combination of ConnectFlags
handler
the Callback to connect. Params: start the start of the range to be deleted; end the end of the range to be deleted