Question

I’m following along with a tutorial that’s building a hangman application in Ruby. It has a function masquerade which hides the word, which is just a country name that’s imported from a file. Problem is I don’t understand how this actually disguises the words, or how the ternary operator is working in inject. It’s checking if the character is blank (i.e. ” “), and, if it is, it’s setting it to blank (i.e. ” “), but if it’s not, it’s making it &nbsp. The function doesn’t seem to deal with the fact that the words have actual characters i.e. letters.

Can anyone explain for this sort of noob, what I’m misunderstanding? Also, why does it add ‘disguise’ again at the end (before the closing }?

def masquerade(word)

      word.each_char.inject([]) { |disguise, char| disguise << (char == " " ? " " : "&nbsp;"); disguise }

end

Examples of game words

Afghanistan
Albania
Algeria
Andorra
Angola
Antigua & Deps
Argentina
Armenia

The whole Word class

class Word

  class << self
    def get_random
      content = File.read("countries.txt")
      words = content.split("\n")
      words[rand(words.size)].upcase
    end

    def masquerade(word)
      word.each_char.inject([]) { |disguise, char| disguise << (char == " " ? " " : "&nbsp;"); disguise }
    end

    def reveal(last_revealed_word, char_clicked, final_word)
      chars = final_word.each_char.to_a

      last_revealed_word.each_index do |i|
        last_revealed_word[i] = chars[i] if last_revealed_word[i] == "&nbsp;" and chars[i] == char_clicked
      end
    end

    def chars_left(revealed_word)
      revealed_word.count { |c| c == "&nbsp;" }
    end

  end

end

Answer 1

Adding disguise at the end is not required. The << already changes the object.

You can see no difference:

[1] pry(main)> "wor d".each_char.inject([]) { |d, c| d << ( c == " " ? " " : "&nbsp;"); d }
=> ["&nbsp;", "&nbsp;", "&nbsp;", " ", "&nbsp;"]

[2] pry(main)> "wor d".each_char.inject([]) { |d, c| d << ( c == " " ? " " : "&nbsp;") }
=> ["&nbsp;", "&nbsp;", "&nbsp;", " ", "&nbsp;"]

upd: Masking here is to replace characters with non-breaking spaces