Advanced C++ Topics

Exception Handling

If an exception is thrown and no catch clause exists to catch it, then the program terminates with an error message.
Because of potential dangers in throwing exceptions, a function can declare that it only throws exceptions of a certain type, or no exceptions at all.
You can use that knowledge to make sure that it is safe to call certain functions, or to know which kinds of exceptions you program needs to catch.
```
void process_products(fstream& fs)
   throw (UnexpectedEndOfFile, bad_alloc)
```
A function signature can optionally be followed by the keyword throw and a parenthesized, comma-separated list of exception types; for example:
To denote that a function throws no exceptions, use an empty exception list.
```
void process_products(fstream& fs)
   throw ()
```
A function without a throw specification is allowed to throw any exceptions.