ActionView::Helpers::CaptureHelper content_for method

Howdy!

I'm trying to do some templating with inhertance from other templates.
While working on this, I stubled on a problem I believe to be caused by
the content_for method.

    # File
vendor/rails/actionpack/lib/action_view/helpers/capture_helper.rb, line
92
92: def content_for(name, content = nil, &block)
93: eval "@content_for_#{name} = (@content_for_#{name} || '') +
capture(&block)"
94: end

There is a parameter :content which is not used at all in the function.
I am curious as to the history behind this. My problem arose from the
fact that content_for will only append to previous content for the same
name. In my application, I need to be able to clear the content for a
block before creating it. I could just clear @content_for#{name}
locally, but that seems like a pretty dirty hack, and something that
could break later on.

Let me know if this has any merit, or if I'm absolutely crazy. The
method looks easy enough to add this functionality without much of a
problem.

-micah