-Each time the "defer" statement
+Each time a "defer" statement
executes, the function value and parameters to the call are
evaluated as usual
-and saved anew but the actual function body is not executed.
-Instead, deferred functions are executed immediately before
+and saved anew but the actual function is not invoked.
+Instead, deferred functions are invoked immediately before
the surrounding function returns, in the reverse order
they were deferred.
+If a deferred function value evaluates
+to nil, execution panics
+when the function is invoked not when the "defer" statement is executed.