7.7. textwrap — Text wrapping and filling

New in version 2.3:

New in version 2.3.

The textwrap module provides two convenience functions, wrap() and fill(), as well as TextWrapper, the class that does all the work, and a utility function dedent(). If you’re just wrapping or filling one or two text strings, the convenience functions should be good enough; otherwise, you should use an instance of TextWrapper for efficiency.

textwrap.wrap(text[, width[, ...]])

Wraps the single paragraph in text (a string) so every line is at most width characters long. Returns a list of output lines, without final newlines.

Optional keyword arguments correspond to the instance attributes of TextWrapper, documented below. width defaults to 70.

textwrap.fill(text[, width[, ...]])

Wraps the single paragraph in text, and returns a single string containing the wrapped paragraph. fill() is shorthand for

"\n".join(wrap(text, ...))

In particular, fill() accepts exactly the same keyword arguments as wrap().

Both wrap() and fill() work by creating a TextWrapper instance and calling a single method on it. That instance is not reused, so for applications that wrap/fill many text strings, it will be more efficient for you to create your own TextWrapper object.

Text is preferably wrapped on whitespaces and right after the hyphens in hyphenated words; only then will long words be broken if necessary, unless TextWrapper.break_long_words is set to false.

An additional utility function, dedent(), is provided to remove indentation from strings that have unwanted whitespace to the left of the text.

textwrap.dedent(text)

Remove any common leading whitespace from every line in text.

This can be used to make triple-quoted strings line up with the left edge of the display, while still presenting them in the source code in indented form.

Note that tabs and spaces are both treated as whitespace, but they are not equal: the lines "  hello" and "\thello" are considered to have no common leading whitespace. (This behaviour is new in Python 2.5; older versions of this module incorrectly expanded tabs before searching for common leading whitespace.)

For example:

def test():
    # end first line with \ to avoid the empty line!
    s = '''\
    hello
      world
    '''
    print repr(s)          # prints '    hello\n      world\n    '
    print repr(dedent(s))  # prints 'hello\n  world\n'

class textwrap.TextWrapper(...)

The TextWrapper constructor accepts a number of optional keyword arguments. Each argument corresponds to one instance attribute, so for example

wrapper = TextWrapper(initial_indent="* ")

is the same as

wrapper = TextWrapper()
wrapper.initial_indent = "* "

You can re-use the same TextWrapper object many times, and you can change any of its options through direct assignment to instance attributes between uses.

The TextWrapper instance attributes (and keyword arguments to the constructor) are as follows:

width

(default: 70) The maximum length of wrapped lines. As long as there are no individual words in the input text longer than width, TextWrapper guarantees that no output line will be longer than width characters.

expand_tabs

(default: True) If true, then all tab characters in text will be expanded to spaces using the expandtabs() method of text.

replace_whitespace

(default: True) If true, each whitespace character (as defined by string.whitespace) remaining after tab expansion will be replaced by a single space.

Note

If expand_tabs is false and replace_whitespace is true, each tab character will be replaced by a single space, which is not the same as tab expansion.

drop_whitespace

(default: True) If true, whitespace that, after wrapping, happens to end up at the beginning or end of a line is dropped (leading whitespace in the first line is always preserved, though).

New in version 2.6:

New in version 2.6: Whitespace was always dropped in earlier versions.