class Async::HTTP::Reference

def expand_path(base, relative)
	if relative.start_with? '/'
		return relative
	else
		path = base.split('/')
		parts = relative.split('/')
		
		parts.each do |part|
			if part == '..'
				path.pop
			else
				path << part
			end
		end
		
		return path.join('/')
	end
end