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

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

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