C6: Batman REPL Game

batman.rb

# display a line on the screen
#
# refactoring to 
# - remove some Ruby jargon by defining a 
#   domain-specific-language (DSL)
# - remove some repetitive (copy-pasted) code
# - have a single place to change the line width
def put_a_line
  puts "*" * 50
end

# ask a question, display the valid options
# and return the answer
#
# refactoring a repeated code pattern into a 
# block "template"
def ask_question(question, options)
  puts question, options
  # downcase: canonicalize your inputs
  gets.chomp.downcase 
end

# display a message on the screen
#
# refactoring to 
# - implement a REPL game DSL
# - do once, apply everywhere
#   - fix a bug: capitalizing the person name
#   - refactor an if-statement
def say(person, message)
  puts(person.nil? ? message : "#{person.capitalize}: #{message}")
end

# display the weapon and the sidekick
#
# refactoring to implement a game DSL that improves
# the readability of the main code below
# even if you don't plan to use this method more than
# once
def display_weapon(weapon, sidekick)
  case weapon
  when "batarang"
    say sidekick, "Awesome! A Batarang! Thanks Batman!"
  when "flashlight"
    say sidekick, "Uh... thanks? I'll make sure to keep the light on you."
  when "fists"
    say sidekick, "I don't need a weapon! I'll just use my fists like you, Batman!"
  else
    say "Don't be selfish. Share your toys with your sidekick."
    weapon = nil
  end
end

#####

put_a_line
say nil, "After all your hardwork, you've finally become Batman."
put_a_line

# sanitize/validate your inputs
options = ["batgirl", "robin"]
begin
  sidekick = ask_question("Who will be your sidekick?", 
    "BatGirl or Robin")
end until options.include? sidekick

put_a_line

weapon = ask_question("Pick a weapon for your sidekick.", 
  "batarang, flashlight, or fists")

display_weapon weapon, sidekick