Time for action – printing with the print() function
We can print using the print()
function as follows:
The old syntax is as follows:
>>> print 'Hello' Hello
The new Python 3 syntax is as follows:
>>> print('Hello') Hello
The parentheses are now mandatory in Python 3. In this book, I try to use the new syntax as much as possible; however, I use Python 2 to be on the safe side. To enforce the syntax, each Python 2 script with
print()
calls in this book starts with:>>> from __future__ import print_function
Try to use the old syntax to get the following error message:
>>> print 'Hello' File "<stdin>", line 1 print 'Hello' ^ SyntaxError: invalid syntax
To print a newline, use the following syntax:
>>> print()
To print multiple items, separate them with commas:
>>> print(2, 'ham', 'egg') 2 ham egg
By default, Python separates the printed values with spaces and prints output to the screen. You can customize these settings. Read more about this function by typing the following command:
>>> help(print)
You can exit again by typing
q
.
What just happened?
We learned about the print()
function and its relation to Python 2 and Python 3.