How to pass data from a view to a partial rendered in a layout?

In the application I'm working on, a layout renders a partial that displays a breadcrumb navigation bar across the top of a page. In other words, the layout renders a partial that displays breadcrumbs.

But the navigation bar rendered by a partial in a layout needs to use data from the view to determine which breadcrumbs to display.

My question is: how can data be passed from a view to a partial rendered in a layout? The ActionController::Layout::ClassMethods explains that data in a view is shared by a partial rendered by the view (using :locals), but I see no reference for how to pass data from a view to a partial being rendered in the layout in which the view "resides." Thanks.

This article explains some different techniques for doing that:

http://www.railsdev.ws/blog/3/modular-page-assembly-in-rails/

-- gw