module Roda::RodaPlugins::AssetsPreloading::InstanceMethods

def preload_assets_link_header(*args)

given asset types/groups.
Return a string suitable for a Link header for the 
def preload_assets_link_header(*args)
  _preload_assets_array(args).map{|path, as| "<#{path}>;rel=preload;as=#{as}"}.join(",")
end