/*============================================================================= Copyright (c) 2001-2011 Hartmut Kaiser http://spirit.sourceforge.net/ 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 //[customize_karma_embedded_container_includes #include #include #include //] /////////////////////////////////////////////////////////////////////////////// //[customize_karma_embedded_container_data namespace client { struct embedded_container { // expose the iterator of the embedded vector as our iterator typedef std::vector::const_iterator iterator; // expose the type of the held data elements as our type typedef std::vector::value_type type; // this is the vector holding the actual elements we need to generate // output from std::vector data; }; } //] //[customize_karma_embedded_container_traits // All specializations of attribute customization points have to be placed into // the namespace boost::spirit::traits. // // Note that all templates below are specialized using the 'const' type. // This is necessary as all attributes in Karma are 'const'. namespace boost { namespace spirit { namespace traits { // The specialization of the template 'is_container<>' will tell the // library to treat the type 'client::embedded_container' as a // container holding the items to generate output from. template <> struct is_container : mpl::true_ {}; // The specialization of the template 'container_iterator<>' will be // invoked by the library to evaluate the iterator type to be used // for iterating the data elements in the container. We simply return // the type of the iterator exposed by the embedded 'std::vector'. template <> struct container_iterator { typedef client::embedded_container::iterator type; }; // The specialization of the templates 'begin_container<>' and // 'end_container<>' below will be used by the library to get the iterators // pointing to the begin and the end of the data to generate output from. // These specializations simply return the 'begin' and 'end' iterators as // exposed by the embedded 'std::vector'. // // The passed argument refers to the attribute instance passed to the list // generator. template <> struct begin_container { static client::embedded_container::iterator call(client::embedded_container const& d) { return d.data.begin(); } }; template <> struct end_container { static client::embedded_container::iterator call(client::embedded_container const& d) { return d.data.end(); } }; }}} //] /////////////////////////////////////////////////////////////////////////////// namespace karma = boost::spirit::karma; int main() { //[customize_karma_embedded_container client::embedded_container d1; // create some test data d1.data.push_back(1); d1.data.push_back(2); d1.data.push_back(3); // use the instance of an 'client::embedded_container' instead of a // STL vector std::cout << karma::format(karma::int_ % ", ", d1) << std::endl; // prints: '1, 2, 3' //] return 0; }