fnmatch — Unix filename pattern matching - Python 3.12.0a3 documentation 编辑

Source code: Lib/fnmatch.py

This module provides support for Unix shell-style wildcards, which are not the same as regular expressions (which are documented in the re module). The special characters used in shell-style wildcards are:

For a literal match, wrap the meta-characters in brackets. For example, '[?]' matches the character '?'.

Note that the filename separator ('/' on Unix) is not special to this module. See module glob for pathname expansion (glob uses filter() to match pathname segments). Similarly, filenames starting with a period are not special for this module, and are matched by the * and ? patterns.

Also note that functools.lru_cache() with the maxsize of 32768 is used to cache the compiled regex patterns in the following functions: fnmatch(), fnmatchcase(), filter().

fnmatch.fnmatch(filename, pattern)

Test whether the filename string matches the pattern string, returning True or False. Both parameters are case-normalized using os.path.normcase(). fnmatchcase() can be used to perform a case-sensitive comparison, regardless of whether that’s standard for the operating system.

This example will print all file names in the current directory with the extension .txt:

import fnmatch
import os

for file in os.listdir('.'):
    if fnmatch.fnmatch(file, '*.txt'):
        print(file)

fnmatch.fnmatchcase(filename, pattern)

Test whether filename matches pattern, returning True or False; the comparison is case-sensitive and does not apply os.path.normcase().

fnmatch.filter(names, pattern)

Construct a list from those elements of the iterable names that match pattern. It is the same as [n for n in names if fnmatch(n, pattern)], but implemented more efficiently.

fnmatch.translate(pattern)

Return the shell-style pattern converted to a regular expression for using with re.match().

Example:

>>> import fnmatch, re
>>>
>>> regex = fnmatch.translate('*.txt')
>>> regex
'(?s:.*\\.txt)\\Z'
>>> reobj = re.compile(regex)
>>> reobj.match('foobar.txt')
<re.Match object; span=(0, 10), match='foobar.txt'>

See also

Module glob

Unix shell-style path expansion.