I've been using content_for a lot to put things in the header like
just appends it all and it all works nicely.
I have a problem where I want to declare a content space like when I
use content for:
<%= yield :help %>
But I want to make any content_for declarations override what was
previously in there.
Specifically I'm using it for help (you might have guessed :-P). I
have a global generic help message, replaced in layouts with a more
specific message, which in turn could be replaced by page specific
help if necessary.
what's the best way of doing this?