hangman.rb

require 'readline'
require 'set'

word = File.readlines('/usr/share/dict/words').sample

letters = word.downcase.chars.to_a
seen = Hash[letters.zip(Array.new(letters.size, false))]
guessed = Set.new

lives = 6

while line = Readline.readline('guess> ', true)
  char = line[/[a-z]/]

  if guessed.include?(char)
    puts "You guessed that already."
  elsif seen.key?(char)
    seen[char] = true
  else
    lives -= 1
  end

  if seen.values.all?
    puts "You win!"
    exit
  end

  guessed << char

  case lives
  when 6
    puts(<<-ASCII)
_____________
|           |
|
|
|
|
|
|
|
|
|
|
    ASCII
  when 5
    puts(<<-ASCII)
_____________
|           |
|           o
|          o o
|          o o
|           o
|
|
|
|
|
|
    ASCII
  when 4
    puts(<<-ASCII)
_____________
|           |
|           o
|          o o
|          o o
|           o
|           |
|           |
|           |
|           |
|           |
|           |
    ASCII
  when 3
    puts(<<-ASCII)
_____________
|           |
|           o
|          o o
|          o o
|           o
|           |
|          /|
|         / |
|           |
|           |
|           |
    ASCII
  when 2
    puts(<<-ASCII)
_____________
|           |
|           o
|          o o
|          o o
|           o
|           |
|          /|\\
|         / | \\
|           |
|           |
|           |
    ASCII
  when 1
    puts(<<-ASCII)
_____________
|           |
|           o
|          o o
|          o o
|           o
|           |
|          /|\\
|         / | \\
|           |
|          /|
|         / |
    ASCII
  when 0
    puts(<<-ASCII)
_____________
|           |
|           o
|          o o
|          o o
|           o
|           |
|          /|\\
|         / | \\
|           |
|          /|\\
|         / | \\
    ASCII
    puts "You lose!"
    puts "The word was #{word}"
    exit
  end

  puts letters.map{|char| seen[char] ? char : "." }.join
end