All the languages we teach have if and else conditionals, and while loops. They're a necessary part of any language, accepted as something of a standard, and we teach them on all the fundamental courses.

Uniquely, Python allows you to add an else clause onto the end of a while loop. Why? So that you can define a block of code that's to be run upon an exit from the loop caused by the loop's condition becoming false, but that's to be skipped over if the loop exits through a break statement or because of an exception.

Here's an example. This program is going to loop, reading in people who are coming to your teenager's party. If you complete the data entry by pressing the "enter" key without entering another name, the <b>else</b> clause on the while is run and your party list is displayed. If you enter "parents" then the party plans are abandoned - you break out of the data entry loop and don't run the else block.


Let's see what that does when we run it



See also Python Programming course

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Python - Conditionals and Loops
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