Python - Exceptions

Exceptions - Python module Y109

There's a limit to how many checks you can build into programs, and some things (such as a connection being lost) that you can't check for at all. Exceptions allow you to try to run a block of code, and if it fails you jump to a block that catches the exception so that you can.

This topic is presented on public course Python Programming

Examples from our training material

bug.py	Program with a bug!
deltemp.py	Use of pass to provide an empty block
insist.py	try and except within a loop
pushit.py	Handling multiple exceptions types
ranger.py	passing exceptions back to calling code
runtime.py	Example of a runtime error
sometimes.py	Example of a piece of code that sometimes crashes
syntax.py	Example of a syntax error
trapper.py	Use of try and except

Opentalk forum discussions related to this topic

Where do add an exception block

Pictures

Python practical on a Public training course in Melksham

Background information

Some modules are available for download as a sample of our material or under an Open Training Notes License for free download from http://www.training-notes.co.uk.

Topics covered in this module

What is an exception?.
Using try and except.
Types of exceptions.
Running mandatory cleanup code.
Raising an exception.
Practical examples - exceptions in use.
Simple application - generate a list of prime numbers.
Code testing and optimisation.

Complete learning

If you are looking for a complete course and not just a information on a single subject, visit our Listing and schedule page.

Well House Consultants specialise in training courses in Python, Perl, PHP, and MySQL. We run Private Courses throughout the UK (and beyond for longer courses), and Public Courses at our training centre in Melksham, Wiltshire, England. It's surprisingly cost effective to come on our public courses - even if you live in a different country or continent to us.

We have a technical library of over 600 books on the subjects on which we teach. These books are available for reference at our training centre. Also available is the Opentalk Forum for discussion of technical questions.