Regex and unicode

Question

I have a script that parses the filenames of TV episodes (show.name.s01e02.avi for example), grabs the episode name (from the www.thetvdb.com API) and automatically renames them into something nicer (Show Name - [01x02].avi)

The script works fine, that is until you try and use it on files that have Unicode show-names (something I never really thought about, since all the files I have are English, so mostly pretty-much all fall within [a-zA-Z0-9'\-])

How can I allow the regular expressions to match accented characters and the likes? Currently the regex's config section looks like..

config['valid_filename_chars'] = """0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!@£$%^&*()_+=-[]{}"'.,<>`~? """
config['valid_filename_chars_regex'] = re.escape(config['valid_filename_chars'])

config['name_parse'] = [
    # foo_[s01]_[e01]
    re.compile('''^([%s]+?)[ \._\-]\[[Ss]([0-9]+?)\]_\[[Ee]([0-9]+?)\]?[^\\/]*$'''% (config['valid_filename_chars_regex'])),
    # foo.1x09*
    re.compile('''^([%s]+?)[ \._\-]\[?([0-9]+)x([0-9]+)[^\\/]*$''' % (config['valid_filename_chars_regex'])),
    # foo.s01.e01, foo.s01_e01
    re.compile('''^([%s]+?)[ \._\-][Ss]([0-9]+)[\.\- ]?[Ee]([0-9]+)[^\\/]*$''' % (config['valid_filename_chars_regex'])),
    # foo.103*
    re.compile('''^([%s]+)[ \._\-]([0-9]{1})([0-9]{2})[\._ -][^\\/]*$''' % (config['valid_filename_chars_regex'])),
    # foo.0103*
    re.compile('''^([%s]+)[ \._\-]([0-9]{2})([0-9]{2,3})[\._ -][^\\/]*$''' % (config['valid_filename_chars_regex'])),
]

Answer 1

Use a subrange of [\u0000-\uFFFF] for what you want.

You can also use the re.UNICODE compile flag. The docs say that if UNICODE is set, \w will match the characters [0-9_] plus whatever is classified as alphanumeric in the Unicode character properties database.

See also http://coding.derkeiler.com/Archive/Python/comp.lang.python/2004-05/2560.html.

Answer 2

\X seems to be available as a generic word-character in some languages, it allows you to match a single character disregarding of how many bytes it takes up. Might be useful.

Answer 3

In Mastering Regular Expressions from Jeffrey Friedl (great book) it is mentioned that you could use \p{Letter} which will match unicode stuff that is considered a letter.