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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11
// <functional>
// template<class T> struct is_placeholder;
// A program may specialize this template for a program-defined type T
// to have a base characteristic of integral_constant<int, N> with N > 0
// to indicate that T should be treated as a placeholder type.
// https://llvm.org/PR51753
#include <functional>
#include <cassert>
#include <type_traits>
struct My2 {};
template<> struct std::is_placeholder<My2> : std::integral_constant<int, 2> {};
int main(int, char**)
{
{
auto f = [](auto x) { return 10*x + 9; };
My2 place;
auto bound = std::bind(f, place);
assert(bound(7, 8) == 89);
}
{
auto f = [](auto x) { return 10*x + 9; };
const My2 place;
auto bound = std::bind(f, place);
assert(bound(7, 8) == 89);
}
{
auto f = [](auto x) { return 10*x + 9; };
My2 place;
auto bound = std::bind(f, std::move(place));
assert(bound(7, 8) == 89);
}
{
auto f = [](auto x) { return 10*x + 9; };
const My2 place;
auto bound = std::bind(f, std::move(place));
assert(bound(7, 8) == 89);
}
return 0;
}
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