def speller
      return @speller if @speller
      # raspell is an optional dependency, handle the missing case nicely
      begin
        require "raspell"
      rescue LoadError
        $stderr.puts "ERROR: Ruby gem \"raspell\" is not installed."
        exit 1
      end

      # initialize aspell
      @speller = Aspell.new("en_US")
      @speller.suggestion_mode = Aspell::NORMAL
      # ignore the HTML tags in the text
      @speller.set_option("mode", "html")

      @speller
    end
def speller
      return @speller if @speller
      # raspell is an optional dependency, handle the missing case nicely
      begin
        require "raspell"
      rescue LoadError
        $stderr.puts "ERROR: Ruby gem \"raspell\" is not installed."
        exit 1
      end

      # initialize aspell
      @speller = Aspell.new("en_US")
      @speller.suggestion_mode = Aspell::NORMAL
      # ignore the HTML tags in the text
      @speller.set_option("mode", "html")

      @speller
    end
create an Aspell speller object
 @return [Aspell] the speller object