lab19: init

lab19/block.rb

@@ -0,0 +1,52 @@
+def do_noisy
+  puts "About to call block"
+  yield
+  puts "Just called block"
+end
+
+do_noisy do
+  puts 3 + 4
+end
+
+
+class Array
+  def each_downcase
+    self.each do |word|
+      yield word.downcase
+    end
+  end
+end
+
+["Alpha", "Beta", "AndSoOn"].each_downcase do |word|
+  puts word
+end
+
+def iff b
+  return if b == false
+  yield
+end
+
+def test_block
+  iff true do
+    puts "hello block"
+    return
+  end
+  puts "goodbye block"
+end
+
+def iff2 b, lam
+  return if b == false
+  lam.call
+end
+
+def test_lambda
+  iff2 true, (lambda do
+      puts "hello lambda"
+      return
+  end)
+  puts "goodbye lambda"
+end
+
+test_block
+test_lambda
+