This class describes an exception thrown when calls to the Block and Unblock methods of a Context object are not properly paired.
class context_unblock_unbalanced : public std::exception;
Overloaded. Constructs a context_unblock_unbalanced object.
Calls to the Block and Unblock methods of a Context object must always be properly paired. The Concurrency Runtime allows the operations to happen in either order. For example, a call to Block can be followed by a call to Unblock, or vice-versa. This exception would be thrown if, for instance, two calls to the Unblock method were made in a row, on a Context object which was not blocked.