[Boost-bugs] [Boost C++ Libraries] #2340: Regex : Invalid preceding regular expression problem

Subject: [Boost-bugs] [Boost C++ Libraries] #2340: Regex : Invalid preceding regular expression problem
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2008-09-18 13:26:40

#2340: Regex : Invalid preceding regular expression problem
-------------------------------+--------------------------------------------
 Reporter:  jcombe_at_[hidden]  |       Owner:  johnmaddock
     Type:  Bugs               |      Status:  new        
Milestone:  To Be Determined   |   Component:  regex      
  Version:  Boost 1.36.0       |    Severity:  Problem    
 Keywords:  regex              |  
-------------------------------+--------------------------------------------
 I have the following code:-

 std::cout << "BUILD REGEX" << std::endl;
 try
 {
    boost::u32regex uregex= boost::make_u32regex (
 "(.*?)(\\b?\\s?)(\\w*?)&(\\w+?)(\\b\\s?&?)(.*)" , boost::regex::perl );
 }
 catch ( boost::regex_error x )
 {
    std::cout << "REGEX ERROR [" << x.what() << "]" << std::endl;
    return false;
 }
 std::cout << "REGEX BUILT" << std::endl;
 return false;

 When I compile this code and then run it, it throws an exception and
 prints this message:-

 REGEX ERROR [Invalid preceding regular expression]

 When I use this line instead

    boost::u32regex uregex= boost::make_u32regex (
 "(.*?)(\\b\\s?)(\\w*?)&(\\w+?)(\\b\\s?&?)(.*)" , boost::regex::perl );

 It does work.

 Both regular expressions compile and run as I expect in Perl. Is it a bug
 that this regex does not work in Boost?

-- 
Ticket URL: <http://svn.boost.org/trac/boost/ticket/2340>
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