Can anyone explain C++ exception specifications to me?

Question

Can anyone explain Exception Specifications as used in C++ ?

• When are they used (I have rarely seen it used in code)
• What are the pros and cons (benefits/

Answer 1

When are they used (I have rarely seen it used in code)
Hopefully never as they are deprecated in the next version of C++ due for standardization next year.

What are the pros and cons (benefits/disadvantages) of using exception specifications?
They provide a way for readers of your code to know exactly what exceptions a function is allowed to throw. The problem is, that if an unexpected exception (one not in the specification) is thrown, then the program will be terminated (by default).