Python the Hard Way - exercise 6 - %r versus %s

Question

http://learnpythonthehardway.org/book/ex6.html

Zed seems to use %r and %s interchangeably here, is there any difference between the two? Wh

Answer 1

%r calls repr, while %s calls str. These may behave differently for some types, but not for others: repr returns "a printable representation of an object", while str returns "a nicely printable representation of an object". For example, they are different for strings:

>>> s = "spam"
>>> print(repr(s))
'spam'
>>> print(str(s))
spam

In this case, the repr is the literal representation of a string (which the Python interpreter can parse into a str object), while the str is just the contents of the string.