libs/parameter/test/parameterized_inheritance.cpp
// Copyright Cromwell D. Enage 2018.
// 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/parameter/config.hpp>
#if !defined(BOOST_PARAMETER_HAS_PERFECT_FORWARDING) && \
(BOOST_PARAMETER_COMPOSE_MAX_ARITY < 3)
#error Define BOOST_PARAMETER_COMPOSE_MAX_ARITY as 3 or greater.
#endif
#include <boost/parameter/name.hpp>
namespace test {
BOOST_PARAMETER_NAME(a0)
BOOST_PARAMETER_NAME(a1)
BOOST_PARAMETER_NAME(a2)
}
#if !defined(BOOST_NO_SFINAE)
#include <boost/parameter/is_argument_pack.hpp>
#include <boost/type_traits/is_convertible.hpp>
#include <boost/core/enable_if.hpp>
#endif
namespace test {
#if !defined(BOOST_NO_SFINAE)
struct _enabler
{
};
#endif
template <typename T>
class backend0
{
T _a0;
public:
template <typename ArgPack>
explicit backend0(
ArgPack const& args
#if !defined(BOOST_NO_SFINAE)
, typename boost::enable_if<
boost::parameter::is_argument_pack<ArgPack>
, test::_enabler
>::type = test::_enabler()
#endif
) : _a0(args[test::_a0])
{
}
#if !defined(BOOST_NO_SFINAE)
template <typename U>
backend0(
backend0<U> const& copy
, typename boost::enable_if<
boost::is_convertible<U,T>
, test::_enabler
>::type = test::_enabler()
) : _a0(copy.get_a0())
{
}
#endif
template <typename Iterator>
backend0(Iterator itr, Iterator itr_end) : _a0(itr, itr_end)
{
}
T const& get_a0() const
{
return this->_a0;
}
protected:
template <typename ArgPack>
void initialize_impl(ArgPack const& args)
{
this->_a0 = args[test::_a0];
}
};
template <typename B, typename T>
class backend1 : public B
{
T _a1;
public:
template <typename ArgPack>
explicit backend1(
ArgPack const& args
#if !defined(BOOST_NO_SFINAE)
, typename boost::enable_if<
boost::parameter::is_argument_pack<ArgPack>
, test::_enabler
>::type = test::_enabler()
#endif
) : B(args), _a1(args[test::_a1])
{
}
#if !defined(BOOST_NO_SFINAE)
template <typename Derived>
backend1(
Derived const& copy
, typename boost::disable_if<
boost::parameter::is_argument_pack<Derived>
, test::_enabler
>::type = test::_enabler()
) : B(copy), _a1(copy.get_a1())
{
}
#endif
T const& get_a1() const
{
return this->_a1;
}
protected:
template <typename ArgPack>
void initialize_impl(ArgPack const& args)
{
B::initialize_impl(args);
this->_a1 = args[test::_a1];
}
};
template <typename B, typename T>
class backend2 : public B
{
T _a2;
public:
template <typename ArgPack>
explicit backend2(
ArgPack const& args
#if !defined(BOOST_NO_SFINAE)
, typename boost::enable_if<
boost::parameter::is_argument_pack<ArgPack>
, test::_enabler
>::type = test::_enabler()
#endif
) : B(args), _a2(args[test::_a2])
{
}
#if !defined(BOOST_NO_SFINAE)
template <typename Derived>
backend2(
Derived const& copy
, typename boost::disable_if<
boost::parameter::is_argument_pack<Derived>
, test::_enabler
>::type = test::_enabler()
) : B(copy), _a2(copy.get_a2())
{
}
#endif
T const& get_a2() const
{
return this->_a2;
}
protected:
template <typename ArgPack>
void initialize_impl(ArgPack const& args)
{
B::initialize_impl(args);
this->_a2 = args[test::_a2];
}
};
}
#include <boost/parameter/preprocessor_no_spec.hpp>
#if !defined(BOOST_NO_SFINAE)
#include <boost/parameter/are_tagged_arguments.hpp>
#endif
namespace test {
template <typename B>
struct frontend : public B
{
BOOST_PARAMETER_NO_SPEC_CONSTRUCTOR(frontend, (B))
#if !defined(BOOST_NO_SFINAE)
template <typename Iterator>
frontend(
Iterator itr
, Iterator itr_end
, typename boost::disable_if<
boost::parameter::are_tagged_arguments<Iterator>
, test::_enabler
>::type = test::_enabler()
) : B(itr, itr_end)
{
}
template <typename O>
frontend(frontend<O> const& copy) : B(copy)
{
}
#endif
BOOST_PARAMETER_NO_SPEC_MEMBER_FUNCTION((void), initialize)
{
this->initialize_impl(args);
}
BOOST_PARAMETER_NO_SPEC_FUNCTION_CALL_OPERATOR((void))
{
this->initialize_impl(args);
}
};
} // namespace test
#include <boost/core/lightweight_test.hpp>
#if !defined(BOOST_NO_SFINAE)
#include <string>
#endif
int main()
{
char const* p = "foo";
char const* q = "bar";
test::frontend<
test::backend2<test::backend1<test::backend0<char const*>, char>, int>
> composed_obj0(test::_a2 = 4, test::_a1 = ' ', test::_a0 = p);
#if defined(BOOST_NO_SFINAE)
test::frontend<
test::backend1<test::backend2<test::backend0<char const*>, int>, char>
> composed_obj1(test::_a0 = p, test::_a1 = ' ', test::_a2 = 4);
#else
test::frontend<
test::backend1<test::backend2<test::backend0<char const*>, int>, char>
> composed_obj1(composed_obj0);
#endif
BOOST_TEST_EQ(composed_obj0.get_a0(), composed_obj1.get_a0());
BOOST_TEST_EQ(composed_obj0.get_a1(), composed_obj1.get_a1());
BOOST_TEST_EQ(composed_obj0.get_a2(), composed_obj1.get_a2());
composed_obj0.initialize(test::_a0 = q, test::_a1 = '!', test::_a2 = 8);
composed_obj1.initialize(test::_a2 = 8, test::_a1 = '!', test::_a0 = q);
BOOST_TEST_EQ(composed_obj0.get_a0(), composed_obj1.get_a0());
BOOST_TEST_EQ(composed_obj0.get_a1(), composed_obj1.get_a1());
BOOST_TEST_EQ(composed_obj0.get_a2(), composed_obj1.get_a2());
composed_obj0(test::_a2 = 8, test::_a1 = '!', test::_a0 = q);
composed_obj1(test::_a0 = q, test::_a1 = '!', test::_a2 = 8);
BOOST_TEST_EQ(composed_obj0.get_a0(), composed_obj1.get_a0());
BOOST_TEST_EQ(composed_obj0.get_a1(), composed_obj1.get_a1());
BOOST_TEST_EQ(composed_obj0.get_a2(), composed_obj1.get_a2());
#if !defined(BOOST_NO_SFINAE)
test::frontend<test::backend0<std::string> > string_wrap(p, p + 3);
BOOST_TEST_EQ(string_wrap.get_a0(), std::string(p));
#endif
return boost::report_errors();
}