Wrap long lines in Python

Question

How do I wrap long lines in Python without sacrificing on the indentation part?

For example, consider this:

>>> def fun():
    print '{0} Here is a really long sentence with {1}'.format(3, 5)

Suppose that this goes over the 79 character recommended limit. The way I read it, here is how to indent it:

    >>> def fun():
        print '{0} Here is a really long \
    sentence with {1}'.format(3, 5)

However, with this approach, there is one problem I have. The indentation of the continued line matches the indentation of the fun(). This looks kinda ugly. I personally feel if someone was to go through my code, it would look bad to have uneven indentation cause of this print statement.

My question is: how do I indent lines such as above effectively without sacrificing code readability?

Answer 1

I'd probably split the long statement up into multiple shorter statements so that the program logic is separated from the definition of the long string:

>>> def fun():
...     format_string = '{0} Here is a really long ' \
...                     'sentence with {1}'
...     print format_string.format(3, 5)

If the string is only just too long and you choose a short variable name then by doing this you might even avoid having to split the string:

>>> def fun():
...     s = '{0} Here is a really long sentence with {1}'
...     print s.format(3, 5)

Answer 2

You can use the fact that Python concatenates string literals which appear adjacent to each other:

>>> def fun():
...     print '{0} Here is a really long ' \
...           'sentence with {1}'.format(3, 5)

Answer 3

You could use the following code where indentation doesn't matter:

>>> def fun():
        return ('{0} Here is a really long'
        ' sentence with {1}').format(3, 5)

You just need to enclose string in the parentheses.

Answer 4

def fun():
    print '{0} Here is a really long ' \
          'sentence with {1}'.format(3, 5)

Adjecent string literals are concatenated at compile time, just as in C. http://docs.python.org/reference/lexical_analysis.html#string-literal-concatenation is a good place to start for more info.