August 4, 2013 02:12 · Aug 4, 2013
diff --git a/bob.rb b/bob.rb
@@ -0,0 +1,50 @@
+class Bob
+  def hey(phrase)
+    think_about(heard(phrase)).respond
+  end
+
+  def heard(phrase)
+    String(phrase)
+  end
+
+  def think_about(might_have_heard)
+    THOUGHTS.find(-> { Default }) { |thought| thought.heard?(might_have_heard) }
+  end
+
+  class << Silent = Object.new
+    def heard?(other)
+      other.empty?
+    end
+
+    def respond
+      "Fine. Be that way."
+    end
+  end
+
+  class << Question = Object.new
+    def heard?(other)
+      other.end_with?("?")
+    end
+
+    def respond
+      "Sure."
+    end
+  end
+
+  class << Shout = Object.new
+    def heard?(other)
+      other == other.upcase
+    end
+
+    def respond
+      "Woah, chill out!"
+    end
+  end
+
+  class << Default = Object.new
+    def respond
+      "Whatever."
+    end
+  end
+  THOUGHTS = [Silent, Question, Shout]
+end