pcre2cpp

pcre2cpp is a C++ wrapper for the PCRE2 (Perl Compatible Regular Expressions) library written in C. It provides an object-oriented interface for the original PCRE2 library, while maintaining the same functionality and behavior.

Features

• Object-oriented interface to PCRE2 10.44.
• Compatible with C++20.
• Easy to use regular expression matching with built-in result capturing.

Installation

To use pcre2cpp, simply download the latest release. There are no additional dependencies required.

1. Download the latest release of pcre2cpp.
2. Link the pcre2cpp library statically in your build system (e.g., CMake or Make).

Example for linking in CMake:

find_package(pcre2cpp REQUIRED)
target_link_libraries(your_project_name PRIVATE pcre2cpp)

Example Usage

Basic Match

#include <pcre2cpp/pcre2cpp.hpp>
#include <iostream>

using namespace std;
using namespace pcre2cpp;

int main() {
    regex expression("\\d+");
    
    if (expression.match("2")) { // is true
        cout << "Matches" << endl;
    }

    if (expression.match("a")) { // is false
        cout << "Matches" << endl;
    }

    if (expression.match("a2")) { // is true
        cout << "Matches" << endl;
    }
    
    return 0;
}

Match with Result

#include <pcre2cpp/pcre2cpp.hpp>
#include <iostream>

using namespace std;
using namespace pcre2cpp;

int main() {
    regex expression("\\d+");
    
    match_result result;
    if (expression.match("aa2", result, 2)) { // is true
        cout << "Matches result: " << result.get_result_value() << " at: " 
             << to_string(result.get_result_global_offset()) << endl;

        // Should print "Matches result: 2 at: 2"
    }
    
    return 0;
}

Match at Specified Offset

#include <pcre2cpp/pcre2cpp.hpp>
#include <iostream>

using namespace std;
using namespace pcre2cpp;

int main() {
    regex expression("\\d+");
    
    if (expression.match_at("aa2", 3, 2)) { // is true
        cout << "Matches result: 2 at: 2" << endl;
    }

    if (expression.match_at("aa2", 3, 1)) { // is false
        cout << "Matches result: 2 at: 2" << endl;
    }
    
    return 0;
}

Match at Specified Offset with Result

#include <pcre2cpp/pcre2cpp.hpp>
#include <iostream>

using namespace std;
using namespace pcre2cpp;

int main() {
    regex expression("\\d+");
    
    match_result result;
    if (expression.match_at("aa2", 3, result, 2)) { // is true
        cout << "Matches result: " << result.get_result_value() << " at: " 
             << to_string(result.get_result_global_offset()) << endl;

        // Should print: "Matches result: 2 at: 2"
    }
    
    return 0;
}

Match with Indexed Subexpression

#include <pcre2cpp/pcre2cpp.hpp>
#include <iostream>

using namespace std;
using namespace pcre2cpp;

int main() {
    regex expression("(\\d+)(a)");
    
    match_result result;
    if (expression.match("ab23a", result, 1)) { // is true
        cout << "Sub Match 0 result: " << result.get_sub_result_value(0) << " at: "
        << result.get_sub_result_global_offset(0) << ", Sub Match 1 result: "
        << result.get_sub_result_value(1) << " at: " 
        << result.get_sub_result_global_offset(1) << endl;

        // Should print: "Sub Match 0 result: 23 at: 2, Sub Match 1 result: a at: 4"
    }
    
    return 0;
}

Match with Named Subexpression

#include <pcre2cpp/pcre2cpp.hpp>
#include <iostream>

using namespace std;
using namespace pcre2cpp;

int main() {
    regex expression("(?<number>\\d+)(?<a>a)");
    
    match_result result;
    if (expression.match("ab23a", result, 1)) { // is true
        cout << "Sub Match <number> result: " << result.get_sub_result_value("number")
        << " at: " << result.get_sub_result_global_offset("number") 
        << ", Sub Match 1 result: " << result.get_sub_result_value("a") 
        << " at: " << result.get_sub_result_global_offset("a") << endl;

        // Should print: "Sub Match <number> result: 23 at: 2, Sub Match <a> result: a at: 4"
    }
    
    return 0;
}

Match All

#include <pcre2cpp/pcre2cpp.hpp>
#include <iostream>

using namespace std;
using namespace pcre2cpp;

int main() {
    regex expression("\\d+");
    
    std::vector<match_result> results;
    if (expression.match_all("Ala ma 23 lata i 3 koty", 23, results)) { // is true
        cout << "Match 0 result: " << results[0].get_result_value() 
        << " at: " << results[0].get_result_global_offset() 
        << ", Match 1 result: " << results[1].get_result_value() 
        << " at: " << results[1].get_result_global_offset() << endl;

        // Should print: "Match 0 result: 23 at: 7, Match 1 result: 3 at: 17"
    }

    match_result* resultsPtr;
    size_t resultsCount;
    if (expression.match_all("Ala ma 23 lata i 3 koty", 23, resultsPtr, resultsCount)) { // is true
        cout << "Match 0 result: " << resultsPtr[0].get_result_value() 
        << " at: " << resultsPtr[0].get_result_global_offset() 
        << ", Match 1 result: " << resultsPtr[1].get_result_value() 
        << " at: " << resultsPtr[1].get_result_global_offset() << endl;

        // Should print: "Match 0 result: 23 at: 7, Match 1 result: 3 at: 17"

        delete[] resultsPtr;
    }
    
    return 0;
}

Offsets Graph

Requirements

• C++20 or newer.

License

This project is licensed under the BSD 3-Clause License with Attribution Requirement. For more details, check the LICENSE file.

Acknowledgments

This project includes code from the PCRE2 library, distributed under the BSD License.