# File lib/action_mailer/vendor/tmail-1.2.3/tmail/interface.rb, line 792 def set_content_type( str, sub = nil, param = nil ) if sub main, sub = str, sub else main, sub = str.split(%r</>, 2) raise ArgumentError, "sub type missing: #{str.inspect}" unless sub end if h = @header['content-type'] h.main_type = main h.sub_type = sub h.params.clear else store 'Content-Type', "#{main}/#{sub}" end @header['content-type'].params.replace param if param str end