gistfile1.txt

# read contents of file if it exists and hasn't already been read and it exists

@@_file_contents ||= (File.read(file_name).strip if File.exists?(file_name))

-- or --

@@_file_contensts ||= File.exists?(file_name) ? File.read(file_name).strip : nil

@@_file_contents ||= if File.exists?(file_name)
                                          File.read(file_name)
                                         end