def command_for(file, line)
      line = line.to_s
      words = Shellwords.shellwords(command)
      words.map! do |word|
        word.gsub!(/%f/, file)
        word.gsub!(/%l/, line)
        word.gsub!(/%%/, '%')
        word
      end
    end
def command_for(file, line)
      line = line.to_s
      words = Shellwords.shellwords(command)
      words.map! do |word|
        word.gsub!(/%f/, file)
        word.gsub!(/%l/, line)
        word.gsub!(/%%/, '%')
        word
      end
    end
Return the editor command for the given file and line.

 This is an array of the command with its arguments.