working through discussion of 7.2

cookbook/007/02.rb

@@ -1,21 +1,14 @@
 def call_twice
-  puts "I'm about to call your block."
-  yield
-  puts "I'm about to call your block again."
-  yield
+  puts "Calling your block."
+  ret1 = yield("very first")
+  puts "The value of your block: #{ret1}"
+
+  puts "Calling your block again."
+  ret2 = yield("second")
+  puts "The value of your block: #{ret2}"
 end
 
-call_twice { puts "Hi, I'm a talking code block." }
-
-
-def repeat(n)
-  if block_given?
-    n.times { yield }
-  else
-    raise ArgumentError.new("I can't repeat a block you don't give me!")
-  end
+call_twice do |which_time|
+  puts "I'm a code block, called for the #{which_time} time."
+  which_time == "very first" ? 1 : 2
 end
-
-repeat(4) { puts "Hello." }
-
-repeat(4)