Re: [boost] Newbie, problem getting regex library to work

From: Charles Fox (charles_at_[hidden])
Date: 2006-11-08 04:11:40

On Tue, 7 Nov 2006, John Maddock wrote:

> Charles Fox wrote:
>> Hi there, I'm new to boost, and am trying to install and test it on a
>> Fedora FC3 machine with gcc 3.4.3.  I have installed boost into the
>> default locations /usr/local/lib  and /usr/local/include/boost-1_33_1
>> respectively with bjam as instructed.  I then try to compile the
>> example regex program (copied below) with this command:
>>
>>     g++ -L/usr/local/lib -I/usr/local/include/boost-1_33_1
>> -lboost_regex-gcc-1_33_1 test.cpp
>>
>> but I get this error:
>> test.cpp: In function `void print_captures(const std::string&, const
>> std::string&)':
>> test.cpp:23: error: 'class boost::smatch' has no member named
>> 'captures' test.cpp:29: error: 'class boost::smatch' has no member
>> named 'captures'
>
> Two points: the -l option always has to appear *after* the source files that
> need the library in question, and the extended-captures information is only
> available when both the library, *and* your code is built with
> BOOST_REGEX_MATCH_EXTRA defined.  See
> http://www.boost.org/libs/regex/doc/captures.html for documentation
> explaining this.  Also note that building with BOOST_REGEX_MATCH_EXTRA
> defined is likely to have an impact on regex performance - you only need it
> if you really want to capture all occurances of a repeated sub-expression:
> normal perl-style sub-expression's work just fine without it.
>
> HTH, John.

Thanks -- I did not realize captures were an optional extra -- yes I am 
happy with the other perl-style matching.
charles