Assume the existence of a File class with boolean data member, isValid, indicating the file is ready for I/O. Write a unary operator, !, that accepts a constant File reference, and returns true if the file is not ready for I/O and false otherwise.

LANGUAGE: C++

CHALLENGE:

Assume the existence of a File class with boolean data member, isValid, indicating the file is ready for I/O. Write a unary operator, !, that accepts a constant File reference, and returns true if the file is not ready for I/O and false otherwise.