some integral data to search int const data = // create a null_regex_traits object for searching integers. It recognizes no character classes and does no case-sensitiveįor example, with null_regex_traits, you can write a static regex toįind a pattern in a sequence of integers as follows: You can search for patterns in raw bytes, integers,Ĭoncept. With xpressive static regexes, you are not limitted to searching for patterns Non-Character Data With null_regex_traits ERROR! Cannot imbue() only part of a regex sregex error = _w > imbue ( loc )( _w ) Searching It is an error to imbue only part of a static regex. Pattern modifier must wrap the entire pattern. */ cpp_regex_traits cpptraits ( loc ) sregex cpprx1 = imbue ( cpptraits )( + _w ) // A shorthand for above sregex cpprx2 = imbue ( loc )( + _w )
Define a regex that uses the global C locale c_regex_traits ctraits sregex crx = imbue ( ctraits )( + _w ) // Define a regex that uses a customized std::locale std :: locale loc = /*. If you want a particular static regex to use a different set of traits, youĬan use the special imbue () pattern modifier. Once they have been imbued with a locale, every regex compile ( "\\w+" ) Īct as regex factories. */ regex_compiler > cpprxcomp ( loc ) cregex cpprx = cpprxcomp. compile ( "\\w+" ) // Declare a regex_compiler that uses a custom std::locale std :: locale loc = /*. Declare a regex_compiler that uses the global C locale regex_compiler > crxcomp cregex crx = crxcomp. The basic steps are shown in the following example: To create a dynamic regex that uses a custom traits object, you must use If you compile with BOOST_XPRESSIVE_USE_C_TRAITSĭefined, then xpressive will use c_regex_traits by default. Regex objects to use the global std :: locale. All traits templates conform toīy default, xpressive uses cpp_regex_traits for all patterns. The second wraps the global C locale, and the third is a stub traits typeįor use when searching non-character data. Three traits class templates: cpp_regex_traits, c_regex_traits and null_regex_traits. The locale-sensitive behavior is captured in a traits class. For example, how are case-insensitive comparisons performed? Matching a regular expression against a string often requires locale-dependent
0 kommentar(er)
