/*<-
Copyright Barrett Adair 2016
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENSE.md or copy at http ://boost.org/LICENSE_1_0.txt)
->*/

#include <boost/callable_traits/config.hpp>
#ifdef CALLABLE_TRAITS_DISABLE_VARIABLE_TEMPLATES
int main(){ return 0; }
#else

//[ intro
#include <type_traits>
#include <tuple>
#include <boost/callable_traits.hpp>

namespace ct = boost::callable_traits;

// This function template helps keep our example code neat
template<typename A, typename B>
void assert_same(){ static_assert(std::is_same<A, B>::value, ""); }

// foo is a function object
struct foo {
    void operator()(int, char, float) const {}
};

int main() {

    // Use args_t to retrieve a parameter list as a std::tuple:
    assert_same<
        ct::args_t<foo>,
        std::tuple<int, char, float>
    >();

    // arg_at_t gives us indexed access to a parameter list
    assert_same<
        ct::arg_at_t<1, foo>,
        char
    >();

    // has_void_return lets us perform a quick check for a void return type
    static_assert(ct::has_void_return_v<foo>, "");

    // Detect C-style variadics (ellipses) in a signature (e.g. printf)
    static_assert(!ct::has_varargs_v<foo>, "");

    // pmf is a pointer-to-member function: void (foo::*)(int, char, float) const
    using pmf = decltype(&foo::operator());

    // remove_member_const_t lets you remove the const member qualifier
    assert_same<
        ct::remove_member_const_t<pmf>,
        void (foo::*)(int, char, float) /*no const!*/
    >();

    // Conversely, add_member_const_t adds a const member qualifier
    assert_same<
        pmf,
        ct::add_member_const_t<void (foo::*)(int, char, float)>
    >();

    // is_const_member_v checks for the presence of member const
    static_assert(ct::is_const_member_v<pmf>, "");

    // pop_front_args_t removes the first parameter from signature:
    assert_same<
        ct::pop_front_args_t<pmf>,
        void (foo::*)(/*int is gone!*/ char, float) const
    >();

    // clear_args_t removes all parameter types:
    assert_same<
        ct::clear_args_t<pmf>,
        void (foo::*)(/* nothing to see here! */) const
    >();
}

// This program is just a glimpse at CallableTraits' features. There
// are many more traits and metafunctions which are not shown here. Every
// feature is demonstrated and specified in the reference documentation.

//]
#endif