Core Python Programming

2.12. while Loop

The standard while conditional loop statement is similar to the if. Again, as with every code sub-block, indentation (and dedentation) are used to delimit blocks of code as well as to indicate which block of code statements belong to:

						while
						expression:
						while_suite
					

The statement suite is executed continuously in a loop until the expression becomes zero or false; execution then continues on the first succeeding statement.

>>> counter = 0
>>> while counter < 5:
…       print 'loop #%d' % (counter)
…       counter = counter + 1

loop #0
loop #1
loop #2
loop #3
loop #4
loop #5

Loops such as while and for (see below) are covered in the loops section of Chapter 8.