Apparently this works very well, except for a single letter, Turkish I. Turkish has two version of 'i' and Unicode folks decided to use the Latin 'i' for lowerc

Apparently this works very well, except for a single letter, Turkish I. Turkish has two version of 'i' and Unicode folks decided to use the Latin 'i' for lowercase dotted i, and Latin 'I' for uppercase dot-less I (and have two new code points for upper-case dotted I and lower-case dot-less I). Now, 'I'.lower() depends on your locale. A cause for a number of security exploits and lots of pain in regular expression engines. edit: Well, apparently 'I'.lower() doesn't depend on locale (so it's incorrect for Turkish languages); in JS you have to do 'I'.toLocaleLowerCase('tr-TR'). Regexps don't support it in neither.