Convert letters to lower case

I use the following with respect to letters from any language:

text = regex.sub("[^\p{alpha}\d]+"," ",text

Can I use p{alpha} to convert letters to their lower case equivalent开发者_如何学C if such an equivalency exists? How would this regex look?

>>> re.sub('[AEIOU]+', lambda m: m.group(0).lower(), 'SOME TEXT HERE')
'SoMe TeXT HeRe'

As oxtopus suggested, you can simply convert letters to their lowercase version with text.lower() (no need for a regular expression). This works with Unicode strings too (À -> à, etc.)

I believe you can find your answer here: http://docs.python.org/library/re.html#re.sub

You can provide a tolower function that takes a match object to the sub method which will return replacement string

You can change the re.findall("([A-Z]+)", text) to use whatever regex you need. This will just go through the matches, and replace each match with its lowercase equivalent:

text = 'ABCDEF_ghjiklm_OPQRSTUVWXYZ'
for f in re.findall("([A-Z]+)", text):
    text = text.replace(f, f.lower())
print text

Output is:

abcdef_ghjiklm_opqrstuvwxyz

in languages like Perl or Js the regex engine supports \L -- python is poor that way