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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_bind_expression;
// A program may specialize this template for a program-defined type T
// to have a base characteristic of true_type to indicate that T should
// be treated as a subexpression in a bind call.
// https://llvm.org/PR51753
#include <functional>
#include <cassert>
#include <type_traits>
struct MyBind {
int operator()(int x, int y) const { return 10*x + y; }
};
template<> struct std::is_bind_expression<MyBind> : std::true_type {};
int main(int, char**)
{
{
auto f = [](auto x) { return 10*x + 9; };
MyBind bindexpr;
auto bound = std::bind(f, bindexpr);
assert(bound(7, 8) == 789);
}
{
auto f = [](auto x) { return 10*x + 9; };
const MyBind bindexpr;
auto bound = std::bind(f, bindexpr);
assert(bound(7, 8) == 789);
}
{
auto f = [](auto x) { return 10*x + 9; };
MyBind bindexpr;
auto bound = std::bind(f, std::move(bindexpr));
assert(bound(7, 8) == 789);
}
{
auto f = [](auto x) { return 10*x + 9; };
const MyBind bindexpr;
auto bound = std::bind(f, std::move(bindexpr));
assert(bound(7, 8) == 789);
}
return 0;
}
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