spirit/classic/example/fundamental/regular_expression.cpp
2017-11-21 19:49:36 +03:00

111 lines
3.5 KiB
C++

/*=============================================================================
Copyright (c) 2002-2003 Hartmut Kaiser
http://spirit.sourceforge.net/
Use, modification and distribution is subject to the Boost Software
License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
http://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/
///////////////////////////////////////////////////////////////////////////////
//
// Demonstrate regular expression parser objects
// See the "Regular Expression Parser" chapter in the User's Guide.
//
// This sample requires an installed version of the boost regex library
// (http://www.boost.org) The sample was tested with boost V1.28.0
//
///////////////////////////////////////////////////////////////////////////////
#include <string>
#include <iostream>
#include <boost/version.hpp>
#include <boost/spirit/include/classic_core.hpp>
///////////////////////////////////////////////////////////////////////////////
//
// The following header must be included, if regular expression support is
// required for Spirit.
//
// The BOOST_SPIRIT_NO_REGEX_LIB PP constant should be defined, if you're
// using the Boost.Regex library from one translation unit only. Otherwise
// you have to link with the Boost.Regex library as defined in the related
// documentation (see. http://www.boost.org).
//
// For Boost > V1.32.0 you'll always have to link against the Boost.Regex
// libraries.
//
///////////////////////////////////////////////////////////////////////////////
#if BOOST_VERSION <= 103200
#define BOOST_SPIRIT_NO_REGEX_LIB
#endif
#include <boost/spirit/include/classic_regex.hpp>
///////////////////////////////////////////////////////////////////////////////
// used namespaces
using namespace std;
using namespace BOOST_SPIRIT_CLASSIC_NS;
///////////////////////////////////////////////////////////////////////////////
// main entry point
int main()
{
const char *ptest = "123 E 456";
const char *prx = "[1-9]+[[:space:]]*E[[:space:]]*";
cout << "Parse " << ptest << " against regular expression: " << prx
<< endl;
// 1. direct use of rxlit<>
rxstrlit<> regexpr(prx);
parse_info<> result;
string str;
result = parse (ptest, regexpr[assign(str)]);
if (result.hit)
{
cout << "Parsed regular expression successfully!" << endl;
cout << "Matched (" << (int)result.length << ") characters: ";
cout << "\"" << str << "\"" << endl;
}
else
{
cout << "Failed to parse regular expression!" << endl;
}
cout << endl;
// 2. use of regex_p predefined parser object
str.empty();
result = parse (ptest, regex_p(prx)[assign(str)]);
if (result.hit)
{
cout << "Parsed regular expression successfully!" << endl;
cout << "Matched (" << (int)result.length << ") characters: ";
cout << "\"" << str << "\"" << endl;
}
else
{
cout << "Failed to parse regular expression!" << endl;
}
cout << endl;
// 3. test the regression reported by Grzegorz Marcin Koczyk (gkoczyk@echostar.pl)
string str1;
string str2;
char const *ptest1 = "Token whatever \nToken";
result = parse(ptest1, rxstrlit<>("Token")[assign(str1)]
>> rxstrlit<>("Token")[assign(str2)]);
if (!result.hit)
cout << "Parsed regular expression successfully!" << endl;
else
cout << "Failed to parse regular expression!" << endl;
cout << endl;
return 0;
}