code for chapter 5 in ruby

05_hash_tables/ruby/01_price_of_groceries.rb

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+# {} is the same as Hash.new
+book = {}
+# an apple costs 67 cents
+book["apple"] = 0.67
+# milk costs $1.49
+book["milk"] = 1.49
+book["avocado"] = 1.49
+puts book

05_hash_tables/ruby/02_check_voter.rb

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+# in order to be accessible from within the check_voter function
+# voted has to be an instance variable (or global / class)
+@voted = {}
+
+def check_voter(name)
+  if @voted.key?(name) && @voted[name]
+    puts "kick them out!"
+  else
+    @voted[name] = true
+    puts "let them vote!"
+  end
+end
+
+check_voter("tom")
+check_voter("mike")
+check_voter("mike")