diff options
Diffstat (limited to 'Lib/exceptions.py')
| -rw-r--r-- | Lib/exceptions.py | 32 |
1 files changed, 20 insertions, 12 deletions
diff --git a/Lib/exceptions.py b/Lib/exceptions.py index 28711df..9c733ce 100644 --- a/Lib/exceptions.py +++ b/Lib/exceptions.py @@ -1,19 +1,23 @@ """Class based built-in exception hierarchy. -This is a new feature whereby all the standard built-in exceptions, -traditionally string objects, are replaced with classes. This gives -Python's exception handling mechanism a more object-oriented feel. +New with Python 1.5, all standard built-in exceptions are now class objects by +default. This gives Python's exception handling mechanism a more +object-oriented feel. Traditionally they were string objects. Python will +fallback to string based exceptions if the interpreter is invoked with the -X +option, or if some failure occurs during class exception initialization (in +this case a warning will be printed). -Most existing code should continue to work with class based -exceptions. Some tricky uses of IOError may break, but the most -common uses should work. +Most existing code should continue to work with class based exceptions. Some +tricky uses of IOError may break, but the most common uses should work. -To disable this feature, start the Python executable with the -X option. +Here is a rundown of the class hierarchy. You can change this by editing this +file, but it isn't recommended. The class names described here are expected +to be found by the bltinmodule.c file. -Here is a rundown of the class hierarchy. You can change this by -editing this file, but it isn't recommended. The classes with a `*' -are new with this feature. They are defined as tuples containing the -derived exceptions when string-based exceptions are used. +The classes with a `*' are new as of Python 1.5. They are defined as tuples +containing the derived exceptions when string-based exceptions are used. If +you define your own class based exceptions, they should be derived from +Exception. Exception(*) | @@ -22,7 +26,11 @@ Exception(*) +-- SystemExit +-- KeyboardInterrupt +-- ImportError - +-- IOError + +-- EnvironmentError(*) + | | + | +-- IOError + | +-- OSError(*) + | +-- EOFError +-- RuntimeError +-- NameError |