invoke.cpp

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/*=============================================================================
    Copyright (c) 2005-2006 Joao Abecasis
    Copyright (c) 2006-2007 Tobias Schwinger

    Use modification and distribution are subject to 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/fusion/functional/invocation/invoke.hpp>
#include <boost/detail/lightweight_test.hpp>

#include <memory>
#include <boost/noncopyable.hpp>

#include <boost/type_traits/is_same.hpp>

#include <boost/mpl/int.hpp>

#include <boost/fusion/container/vector.hpp>
#include <boost/fusion/container/list.hpp>
#include <boost/fusion/sequence/intrinsic/size.hpp>
#include <boost/fusion/sequence/intrinsic/begin.hpp>
#include <boost/fusion/view/single_view.hpp>
#include <boost/fusion/view/iterator_range.hpp>
#include <boost/fusion/iterator/advance.hpp>
#include <boost/fusion/algorithm/transformation/join.hpp>

namespace mpl = boost::mpl;
namespace fusion = boost::fusion;

template <typename T>
inline T const & const_(T const & t)
{
    return t;
}

struct object {};
struct object_nc : boost::noncopyable {};

struct fobj
{
    // Handle nullary separately to exercise result_of support
    template <typename Sig>
    struct result;

    template <class Self, typename T0>
    struct result< Self(T0) >
    {
        typedef int type;
    };

    template <class Self, typename T0, typename T1>
    struct result< Self(T0, T1) >
    {
        typedef int type;
    };

    template <class Self, typename T0, typename T1, typename T2>
    struct result< Self(T0, T1, T2) >
    {
        typedef int type;
    };

    int operator()(int i)       { return 2 + i; }
    int operator()(int i) const { return 3 + i; }

    int operator()(int i, object &)             { return 4 + i; }
    int operator()(int i, object &) const       { return 5 + i; }
    int operator()(int i, object const &)       { return 6 + i; }
    int operator()(int i, object const &) const { return 7 + i; }

    int operator()(int i, object &, object_nc &)       { return 10 + i; }
    int operator()(int i, object &, object_nc &) const { return 11 + i; }
};

struct nullary_fobj
{
    typedef int result_type;

    int operator()()       { return 0; }
    int operator()() const { return 1; }
};

struct fobj_nc
      : boost::noncopyable
{
    // Handle nullary separately to exercise result_of support
    template <typename Sig>
    struct result;

    template <class Self, typename T0>
    struct result< Self(T0)>
    {
        typedef int type;
    };

    int operator()(int i)       { return 14 + i; }
    int operator()(int i) const { return 15 + i; }
};

struct nullary_fobj_nc
      : boost::noncopyable
{
    typedef int result_type;

    int operator()()       { return 12; }
    int operator()() const { return 13; }
};

int nullary() { return 16; }
int unary(int i) { return 17 + i; }
int binary1(int i, object &) { return 18 + i; }
int binary2(int i, object const &) { return 19 + i; }

typedef int (*                   func_ptr)(int);
typedef int (* const           c_func_ptr)(int);
typedef int (* volatile        v_func_ptr)(int);
typedef int (* const volatile cv_func_ptr)(int);

   func_ptr func_ptr1 = &unary;
 c_func_ptr func_ptr2 = &unary;
 v_func_ptr func_ptr3 = &unary;
cv_func_ptr func_ptr4 = &unary;

class members
{
  public:
    int data;

    members()
        : data(20)
    { }

    int nullary() { return data + 1; }
    int nullary_c() const { return data + 2; }
    int unary(int i) { return data + 3 + i; }
    int unary_c(int i) const { return data + 4 + i; }
    int binary(int i, object) { return data + 5 + i; }
    int binary_c(int i, object) const { return data + 6 + i; }
};

struct derived
    : members
{
};

typedef int         element1_type;
typedef object      element2_type;
typedef object_nc & element3_type;

int         element1 = 100;
object      element2 = object();
object_nc   element3;

members that;

std::auto_ptr<members> spt_that(new members);
std::auto_ptr<members const> spt_that_c(new members);

fusion::single_view<members  > sv_obj_ctx(  that);
fusion::single_view<members &> sv_ref_ctx(  that);
fusion::single_view<members *> sv_ptr_ctx(& that);
fusion::single_view<members const  > sv_obj_c_ctx(  that);
fusion::single_view<members const &> sv_ref_c_ctx(  that);
fusion::single_view<members const *> sv_ptr_c_ctx(& that);
fusion::single_view<std::auto_ptr<members> const &> sv_spt_ctx(spt_that);
fusion::single_view< std::auto_ptr<members const> const &> sv_spt_c_ctx(spt_that_c);

derived derived_that;

std::auto_ptr<derived> spt_derived_that(new derived);
std::auto_ptr<derived const> spt_derived_that_c(new derived);

fusion::single_view<derived  > sv_obj_d_ctx(  derived_that);
fusion::single_view<derived &> sv_ref_d_ctx(  derived_that);
fusion::single_view<derived *> sv_ptr_d_ctx(& derived_that);
fusion::single_view<derived const  > sv_obj_c_d_ctx(  derived_that);
fusion::single_view<derived const &> sv_ref_c_d_ctx(  derived_that);
fusion::single_view<derived const *> sv_ptr_c_d_ctx(& derived_that);
fusion::single_view<std::auto_ptr<derived> const &> sv_spt_d_ctx(spt_derived_that);
fusion::single_view< std::auto_ptr<derived const> const &> sv_spt_c_d_ctx(spt_derived_that_c);

template <class Sequence>
void test_sequence_n(Sequence & seq, mpl::int_<0>)
{
    // Function Objects

    nullary_fobj f;

    BOOST_TEST(f () == fusion::invoke(f ,        seq ));
    BOOST_TEST(f () == fusion::invoke(f , const_(seq)));

    // Note: The function object is taken by value, so we request the copy
    // to be const with an explicit template argument. We can also request
    // the function object to be pased by reference...
    BOOST_TEST(const_(f)() == fusion::invoke<nullary_fobj const  >(const_(f),        seq ));
    BOOST_TEST(const_(f)() == fusion::invoke<nullary_fobj const &>(const_(f), const_(seq)));