working program assumptions

run.rb

@@ -1,3 +1,26 @@
+def describe(description, &block)
+  ExampleGroup.new(block).evaluate
+end
+
+class ExampleGroup
+
+  def initialize(block)
+    @block = block
+  end
+
+  def evaluate
+    # we are using instance_eval because otherwise we are working in describe method context, where program don't know about it method
+    # by usind self.instance eval, we are executing provided block code inside ExampleGroup class, that mean, program knows about it method
+    self.instance_eval(&@block)
+  end
+
+  def it(description, &block)
+    block.call
+  end
+
+end
+
+
 describe "Amazing RSpeclike example" do
   it "works!" do
     puts "hello"