FAQ 9.06 What are the advantages of throw ... catch ?

FAQ 9.06 What are the advantages of throw...catch?

Clarity, compiler support, and runtime support.

The most important advantage is that throw...catch clearly separates normal logic from exception-handling logic. In contrast, when a function call uses return codes to signal exceptions, the caller must check the return code with control flow logic (if). This mingles normal logic with exception-handling logic, increasing the complexity of both paths.

A second advantage is that throw...catch can transmit an arbitrarily large amount of information from the throw point to the catch point. This is because C++ allows arbitrary objects, as opposed to just simple data types, to be thrown, and these objects can carry behavior as well as data from where the error is detected to where the error is handled. In contrast return codes are almost always simple data types such as int.

Also, throw...catch allows different error handlers to be defined for different types of objects and automatically transfers control to the correct error handler.

Finally, throw...catch is suited for OO programming. In contrast, return codes are ill suited for OO: since many member functions tend to be short, return codes would overwhelm the routine's normal logic with error-handling logic.