A number of readers have the mysterious fifth sense which gives them the ability to deduce that the GetBars method from yesterday's post contains a yield return and is therefore an iterator. Remember, as the standard states (in section 10.14.4): [...] execution of the code in the iterator block occurs...

Here is a compiler bug report I got the other day. The user is trying to write a unit test for a method which takes a Foo and returns a collection of Bar s. The test is supposed to confirm that GetBars throws an exception if the argument is null . The test was failing with “got no exception”. The user...