文件名称：Perl-compatible Regular Expressions VC compile project
文件大小：51KB
文件格式：ZIP
更新时间：2012-04-02 16:18:05
PCRE
The PCRE library is a set of functions that implement regular expression pattern matching using the same syntax and semantics as Perl, with just a few differences. Certain features that appeared in Python and PCRE before they appeared in Perl are also available using the Python syntax. There is also some support for certain .NET and Oniguruma syntax items, and there is an option for requesting some minor changes that give better JavaScript compatibility. The current implementation of PCRE (release 7.x) corresponds approximately with Perl 5.10, including support for UTF-8 encoded strings and Unicode general category properties. However, UTF-8 and Unicode support has to be explicitly enabled; it is not the default. The Unicode tables correspond to Unicode release 5.0.0. In addition to the Perl-compatible matching function, PCRE contains an alternative matching function that matches the same compiled patterns in a different way. In certain circumstances, the alternative function has some advantages. For a discussion of the two matching algorithms, see the pcrematching page. PCRE is written in C and released as a C library. A number of people have written wrappers and interfaces of various kinds. In particular, Google Inc. have provided a comprehensive C++ wrapper. This is now included as part of the PCRE distribution. The pcrecpp page has details of this interface. Other people's contributions can be found in the Contrib directory at the primary FTP site, which is: ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre Details of exactly which Perl regular expression features are and are not supported by PCRE are given in separate documents. See the pcrepattern and pcrecompat pages. There is a syntax summary in the pcresyntax page. Some features of PCRE can be included, excluded, or changed when the library is built. The pcre_config() function makes it possible for a client to discover which features are available. The features themselves are described in the pcrebuild page. Documentation about building PCRE for various operating systems can be found in the README file in the source distribution. The library contains a number of undocumented internal functions and data tables that are used by more than one of the exported external functions, but which are not intended for use by external callers. Their names all begin with "_pcre_", which hopefully will not provoke any name *es. In some environments, it is possible to control which external symbols are exported when a shared library is built, and in these cases the undocumented symbols are not exported.