Passing optional local variables to a partial

In verbose_index.html.erb i want to pass some additional parameters to the _thing.html.erb partial:

<% @things.each do |thing| %>

<%= render :partial => thing,

:locals => {:some_extra_stuff => some_extra_stuff} %>

<% end %>

in index.html.erb i do not want to pass any additional parameters to the _thing.html.erb partial:

<%= render :partial => things %>

when I hit verbose_index everything will work fine. but when I hit index, I'll see this error:

undefined local variable or method 'some_extra_stuff'

for #

to fix, in _thing.html.erb I add a check to see if the local variable is assigned:

<% unless local_assigns[:some_extra_stuff].nil? %>

<%= some_extra_stuff %>

<% end %>