Assertions

In the Debug environment, the ASSERT macro evaluates a specified condition. If the condition is false, the macro prints the source filename and the line number, then it terminates the program . In the Release environment, the statement has no effect.

VERIFY, a companion macro, evaluates the condition in both the Debug and Release environments. It prints and terminates only in the Debug environment.

With Windows, ASSERT and VERIFY display their messages in a pop-up
dialog box.