Format parameter in RESTful named routes

In my application I have a RESTful named route:

map.resources :discussions

And I'm attempting to generate a URL like:

/discussions/27.atom

using the discussion_url helper method.

The following:

discussion_url(:id => @discussion.id, :format => 'atom')

just generates /discussions/27, ignoring the format parameter.

Anyone know the correct way of doing this? As far as I can see, the docs have nothing to say on the matter.

Ta, Ben

Ben :

In my application I have a RESTful named route:

map.resources :discussions

And I'm attempting to generate a URL like:

/discussions/27.atom

using the discussion_url helper method.

The following:

discussion_url(:id => @discussion.id, :format => 'atom')

formatted_discussion_url(:id => @discussion.id, :format => :atom)

   -- Jean-François.