libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/default.pass.cpp

//===----------------------------------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// <functional>

// class function<R(ArgTypes...)>

// explicit function();

#include <functional>
#include <cassert>

int main()
{
    std::function<int(int)> f;
    assert(!f);
}