gistfile1.txt

require 'yaml'
require 'open-uri'

URL = "https://github.com/TheNotary/the_notarys_linux_mint_postinstall_configuration"

def valid_yaml_string?(yaml)
  !!YAML.load(yaml)
rescue Exception => e
  STDERR.puts e.message
  return false
end

puts valid_yaml_string?(open(URL).read)

#  http://stackoverflow.com/questions/16329059/ruby-check-if-valid-yaml