module Roda::RodaPlugins::EarlyHints::InstanceMethods

def send_early_hints(hash)

key 'Link', and a string or array of strings for each of the early hints.
currenly only supported by puma. hash given should generally have the single
Send given hash of Early Hints using the rack.early_hints environment variable, 
def send_early_hints(hash)
  if eh_proc = env['rack.early_hints']
    eh_proc.call(hash)
  end
end