libs/phoenix/example/container_actor.cpp
/*==============================================================================
Copyright (c) 2005-2010 Joel de Guzman
Copyright (c) 2010 Thomas Heller
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 <boost/phoenix/core.hpp>
#include <boost/phoenix/function.hpp>
#include <boost/phoenix/stl/container.hpp>
#include <boost/phoenix/stl/algorithm.hpp>
#include <vector>
#include <iostream>
namespace phoenix = boost::phoenix;
using phoenix::actor;
using phoenix::function;
using phoenix::arg_names::arg1;
struct size_impl
{
// result_of protocol:
template <typename Sig>
struct result;
template <typename This, typename Container>
struct result<This(Container)>
{
// Note, remove reference here, because Container can be anything
typedef typename boost::remove_reference<Container>::type container_type;
// The result will be size_type
typedef typename container_type::size_type type;
};
template <typename Container>
typename result<size_impl(Container const&)>::type
operator()(Container const& container) const
{
return container.size();
}
};
template <typename Expr>
struct container_actor
: actor<Expr>
{
typedef actor<Expr> base_type;
typedef container_actor<Expr> that_type;
container_actor( base_type const& base = base_type() )
: base_type( base ) {}
typename phoenix::expression::function<phoenix::stl::begin, that_type>::type const
begin() const
{
return phoenix::begin(*this);
}
typename phoenix::expression::function<phoenix::stl::end, that_type>::type const
end() const
{
return phoenix::end(*this);
}
typename phoenix::expression::function<size_impl, that_type>::type const
size() const
{
function<size_impl> const f = size_impl();
return f(*this);
}
typename phoenix::expression::function<phoenix::stl::max_size, that_type>::type const
max_size() const
{
return phoenix::max_size(*this);
}
typename phoenix::expression::function<phoenix::stl::empty, that_type>::type const
empty() const
{
return phoenix::empty(*this);
}
template <typename Container>
typename phoenix::expression::function<phoenix::impl::swap, that_type, Container>::type const
swap(actor<Container> const& expr) const
{
return phoenix::swap(*this, expr);
}
};
template <typename Expr>
container_actor<Expr> const
container( actor<Expr> const& expr )
{
return expr;
}
int main()
{
container_actor<phoenix::expression::argument<1>::type> const con1;
std::vector<int> v;
v.push_back(0);
v.push_back(1);
v.push_back(2);
v.push_back(3);
std::cout << (container(arg1).size())(v) << " == " << v.size() << "\n";
std::cout << (con1.size())(v) << " == " << v.size() << "\n";
}