module ActionView::Helpers::CaptureHelper

the layout to stop looking for more contents.
template, you should use +content_for+, if not, use +provide+ to tell
concatenate several times to the same buffer when rendering a given
straight back to the layout. In other words, if you want to
The same as +content_for+ but when used with streaming flushes

def provide(name, content = nil, &block)
  content = capture(&block) if block_given?
  result = @view_flow.append!(name, content) if content
  result unless content
end