[regex] Working with wchar_t on older UNIX platforms
Hi! I am experiencing a problem with integrating boost::regex into one of software projects. The problem is that the project supports a number of old operating systems (such as AIX 4.3.3 and HP-UX 11.00), where full support for functions working with wide characters (wchar_t) does not exist. This causes GCC to be compiled without wstring support. On the other hand, we do use wchar_t to the extent allowed by these operating systems and find the limited support more or less enough. Now I tried to integrate wregex in the software, but it just would not compile complaining about missing wstring (and defined BOOST_NO_WREGEX). I tried to make up my own regex character traits class, but this does not seem to help, because some other classes/types (such as sub_match) make use of basic_string<charT>. Is there any way to bypass the problem? I could be using the plain-char version of regex, but that causes me problems with determining the position of a match in the original wide-character string (conversion from wchar_t to char could involve some multibyte encoding). Thanks, -- ANDREI TARASSOV Software Engineer III Altiris OÜ T > +372 6507154 M > +372 53403298 www.altiris.com Security. Compliance. Patch management. IT service management. Altiris solves your most pressing IT issues. www.altiris.com
Now I tried to integrate wregex in the software, but it just would not compile complaining about missing wstring (and defined BOOST_NO_WREGEX). I tried to make up my own regex character traits class, but this does not seem to help, because some other classes/types (such as sub_match) make use of basic_string<charT>.
Is there any way to bypass the problem?
OK all the following comments apply to 1.33.1. There are two easy options and one harder option: Easy option #1, use STLport if it supports wstring. Easy option #2, use the ICU/Unicode support in 1.33.1 to search your data directly (as long as it's in UTF-8, UTF-16 or UTF-32 format). You'll get back iterators into your data (whatever encoding it's in), so there's no problems determining offsets etc. The slightly harder option, as you've guessed already: write your own traits class, from 1.33 onwards you can use vector<charT> in place of basic_string<charT> in the traits class. If you take a look at the traits class used by the Unicode/ICU support code it should give you the general idea, and there are docs here: http://www.boost.org/libs/regex/doc/concepts.html#traits And finally... if you data is in MBCS format you might get some ideas from the unicode suuport code in 1.33.x: basically in order to handle multibyte encodings it converts from UTF-8 or UTF-16 to UTF-32 code points on the fly. Of course this requires that the on-the-fly conversions are bidirectional, this works OK for Unicode, but I'm not sure about how far you would get with other encodings. HTH, John.
participants (2)
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Andrei Tarassov -
John Maddock