cxx/test/thread/futures/futures.tas/futures.task.members/get_future.pass.cpp
Howard Hinnant b64f8b07c1 license change
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@119395 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-16 22:09:02 +00:00

63 lines
1.4 KiB
C++

//===----------------------------------------------------------------------===//
//
// 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.
//
//===----------------------------------------------------------------------===//
// <future>
// class packaged_task<R(ArgTypes...)>
// future<R> get_future();
#include <future>
#include <cassert>
class A
{
long data_;
public:
explicit A(long i) : data_(i) {}
long operator()(long i, long j) const {return data_ + i + j;}
};
int main()
{
{
std::packaged_task<double(int, char)> p(A(5));
std::future<double> f = p.get_future();
p(3, 'a');
assert(f.get() == 105.0);
}
{
std::packaged_task<double(int, char)> p(A(5));
std::future<double> f = p.get_future();
try
{
f = p.get_future();
assert(false);
}
catch (const std::future_error& e)
{
assert(e.code() == make_error_code(std::future_errc::future_already_retrieved));
}
}
{
std::packaged_task<double(int, char)> p;
try
{
std::future<double> f = p.get_future();
assert(false);
}
catch (const std::future_error& e)
{
assert(e.code() == make_error_code(std::future_errc::no_state));
}
}
}