gistfile1.rb

    def guarded(task)
      %x{#{task}}.tap { raise "bad exit" if $?.exitstatus!=0 }
    rescue => e
      yield e if block_given?
    end

    guarded("git config --global github.token") do |error|
      abort "please add your token to ~/.gitconfig with git config --global github.token MYTOKEN"
    end