mirror/example/factories/physical_units.cpp

This example shows how to use a factory created by the factory generator with a xml parsing plugin to generically construct instances of classes with non default constructors, from input strings.

Copyright 2006-2011 Matus Chochlik. Distributed under 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)

#include <mirror/mirror_base.hpp>
#include <mirror/pre_registered/type/native.hpp>
#include <mirror/pre_registered/type/std/string.hpp>
#include <mirror/pre_registered/class/std/list.hpp>
#include <mirror/pre_registered/class/std/map.hpp>
#include <mirror/utils/rapidxml_factory.hpp>
#include <iostream>

int main(void)
{
    using namespace mirror;
    //
    // make the input object for the factory
    rapidxml_factory_input in;
    // create a factory plugged with the rapidxml parser
    typedef std::map<std::string, std::list<std::string> > unit_map;
    rapidxml_factory_maker::factory<unit_map>::type f = in.data();
    //
    const char xml[] = " \
        <?xml version='1.0' encoding='utf-8' ?> \
        <data> \
          <quantity first='length'> \
            <second> \
              <unit name='meter'/> \
              <unit name='inch'/> \
              <unit name='foot'/> \
              <unit name='yard'/> \
              <unit name='mile'/> \
              <unit name='furlong'/> \
              <unit name='parsec'/> \
              <unit name='lightyear'/> \
            </second> \
          </quantity> \
          <quantity first='mass'> \
            <second> \
              <unit name='kilogram'/> \
              <unit name='tonne'/> \
              <unit name='pound'/> \
            </second> \
          </quantity> \
          <quantity first='time'> \
            <second> \
              <unit name='second'/> \
              <unit name='minute'/> \
              <unit name='hour'/> \
              <unit name='week'/> \
              <unit name='fortnight'/> \
              <unit name='month'/> \
              <unit name='year'/> \
            </second> \
          </quantity> \
          <quantity first='electric current'> \
            <second> \
              <unit name='ampere'/> \
            </second> \
          </quantity> \
          <quantity first='temperature'> \
            <second> \
              <unit name='Kelvin'/> \
              <unit name='degrees Celsius'/> \
              <unit name='degrees Fahrenheit'/> \
              <unit name='degrees Rankine'/> \
            </second> \
          </quantity> \
        </data> \
    ";

    rapidxml::xml_document<> doc;
    doc.parse<rapidxml::parse_non_destructive>((char*)xml);
    in.set(doc.first_node("data"));
    unit_map units(f());
    //
    for(auto i = units.begin(), e = units.end(); i != e; ++i)
    {
        std::cout << "Some units for '" << i->first << "': '";
        auto j = i->second.begin(), f = i->second.end();
        while(j != f)
        {
            std::cout << *j;
            ++j;
            if(j == f) std::cout << "'.";
            else std::cout << "', '";
        }
        std::cout << std::endl;
    }
    //
    return 0;
}

/* Example of output:
Some units for 'electric current': 'ampere'.
Some units for 'length': 'meter', 'inch', 'foot', 'yard', 'mile', 'furlong', 'parsec', 'lightyear'.
Some units for 'mass': 'kilogram', 'tonne', 'pound'.
Some units for 'temperature': 'Kelvin', 'degrees Celsius', 'degrees Fahrenheit', 'degrees Rankine'.
Some units for 'time': 'second', 'minute', 'hour', 'week', 'fortnight', 'month', 'year'.
 */