Python Pocket Reference, 3rd Edition

Specific Statements

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Extended print form

The print statement can also name an open output file-like

object to be the target of the printed text (instead of

sys.

stdout

):

fileobj = open('log', 'a')

print >> fileobj, "Warning-bad spam!"

If the file object is None, sys.stdout is used. Because sys.

stdout

can be reassigned, the >> form is not strictly needed;

however, it can often avoid both explicit

write method calls

and saving and restoring the original

sys.stdout value

around a redirected

print.

The if Statement

if test:

suite

[elif test:

suite]*

[else:

suite]

The if statement selects from among one or more actions

(statement blocks), and it runs the suite associated with the

first

if or elif test that is true, or the else suite if all are

false.

The while Statement

while test:

suite

[else:

suite]

The while loop is a general loop that keeps running the first

suite while the test at the top is true. It runs the

else suite if

the loop exits without hitting a

break statement.