Descargar pfr - Descargar el código fuente de pfr

pfr

C/C++

2.2.0

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Boost.PFR

Esta es una biblioteca C ++ 14 para una reflexión muy básica que le brinda acceso a los elementos de estructura por índice y proporciona otros métodos de std::tuple para el usuario sin ningún código de macro o calderera.

BOOST.PFR es parte de las bibliotecas Boost C ++. Sin embargo, BOOST.PFR es una biblioteca de solo encabezado que no depende de Boost. Puede copiar el contenido de la carpeta "Incluir" desde el GitHub en su proyecto, y la biblioteca funcionará bien.

Para una versión de la biblioteca sin boost:: Namespace, ver PFR.

Resultados de las pruebas

Sucursales	Construir	Cobertura de prueba	Más información
Desarrollar:			detalles...
Maestro:			detalles...

Última documentación del desarrollador

Ejemplo motivador #0

# include < iostream >
# include < fstream >
# include < string >

# include " boost/pfr.hpp "

struct some_person {
  std::string name;
  unsigned birth_year;
};

int main ( int argc, const char * argv[]) {
  some_person val{ " Edgar Allan Poe " , 1809 };

  std::cout << boost::pfr::get< 0 >(val)                // No macro!
      << " was born in " << boost::pfr::get< 1 >(val);  // Works with any aggregate initializables!

  if (argc > 1 ) {
    std::ofstream ofs (argv[ 1 ]);
    ofs << boost::pfr::io (val);                       // File now contains: {"Edgar Allan Poe", 1809}
  }
}

Salidas:

 Edgar Allan Poe was born in 1809

Ejecute la muestra anterior

Ejemplo motivador #1

# include < iostream >
# include " boost/pfr.hpp "

struct my_struct { // no ostream operator defined!
    int i;
    char c;
    double d;
};

int main () {
    my_struct s{ 100 , ' H ' , 3.141593 };
    std::cout << " my_struct has " << boost::pfr::tuple_size<my_struct>::value
        << " fields: " << boost::pfr::io (s) << " n " ;
}

Salidas:

 my_struct has 3 fields: {100, H, 3.14159}

Ejemplo motivador #2

# include < iostream >
# include " boost/pfr.hpp "

struct my_struct { // no ostream operator defined!
    std::string s;
    int i;
};

int main () {
    my_struct s{{ " Das ist fantastisch! " }, 100 };
    std::cout << " my_struct has " << boost::pfr::tuple_size<my_struct>::value
        << " fields: " << boost::pfr::io (s) << " n " ;
}

Salidas:

 my_struct has 2 fields: {"Das ist fantastisch!", 100}

Ejemplo motivador #3

# include < iostream >
# include < string >

# include < boost/config/warning_disable.hpp >
# include < boost/spirit/home/x3.hpp >
# include < boost/fusion/include/adapt_boost_pfr.hpp >

# include " boost/pfr/io.hpp "

namespace x3 = boost::spirit::x3;

struct ast_employee { // No BOOST_FUSION_ADAPT_STRUCT defined
    int age;
    std::string forename;
    std::string surname;
    double salary;
};

auto const quoted_string = x3::lexeme[ ' " ' >> +(x3::ascii::char_ - ' " ' ) >> ' " ' ];

x3::rule< class employee , ast_employee> const employee = " employee " ;
auto const employee_def =
    x3::lit ( " employee " )
    >> '{ '
    >>  x3::int_ >> ' , '
    >>  quoted_string >> ' , '
    >>  quoted_string >> ' , '
    >>  x3::double_
    >>  ' } '
    ;
BOOST_SPIRIT_DEFINE(employee);

int main() {
    std::string str = R"(employee{34, "Chip", "Douglas", 2500.00})";
    ast_employee emp;
    x3::phrase_parse(str.begin(),
                     str.end(),
                     employee,
                     x3::ascii::space,
                     emp);
    std::cout << boost::pfr::io(emp) << std::endl;
}