Core Python Programming

10.9. *Creating Exceptions

Although the set of standard exceptions is fairly wide-ranging, it may be advantageous to create your own exceptions. One situation is where you would like additional information from what a standard or module-specific exception provides. We will present two examples, both related to IOError.

IOError is a generic exception used for input/output problems which may arise from invalid file access or other forms of communication. Suppose we wanted to be more specific in terms of identifying the source of the problem. For example, for file errors, we want to have a FileError exception which behaves like IOError, but with a name that has more meaning when performing file operations.

Another exception we will look at is related ...