在C++中,当需要从线程中返回一个std::vector时,可以使用std::future和std::promise来实现异步结果的获取。下面将分步说明如何实现这一功能: 1. 创建一个C++线程函数,该函数返回一个std::vector 由于C++标准线程库(std::thread)不直接支持返回类型,我们可以通过线程函数内的std::promise对象来存储结果,并通过std:...
总结一下，其实vector x=v这步并不是原子操作，它分两步，申请内存和copy数据（copy时会重重新计算大...
std::vector Defined in header<vector> template< classT, classAllocator=std::allocator<T> >classvector; (1) namespace { template<classT> usingvector=std::vector<T,std::pmr::polymorphic_allocator<T>>; } (2) (since C++17) 1)std::vectoris a sequence container that encapsulates dynamic siz...
voidAssign(std::future<void>&& future){std::lock_guard<std::mutex> lock(mutex); futures.emplace_back(std::move(future)); EraseReady(); } 开发者ID:arrrrrrr,项目名称:ebftpd,代码行数:6,代码来源:futureminder.hpp 示例8: boolean ▲点赞 1▼ boolboolean(constboolval){ m_items.emplace_back(...
// resize() is useful when you know that the vector will not be resized in the future. std::vector<int> c = {1, 2, 3}; std::cout << "The vector holds: "; for(auto& el: c) std::cout << el << ' '; std::cout << '\n'; c.resize(5); std::cout << "After resi...
assert(*_closed);for(typenamestd::vector< Future<T> >::iterator it =this->_futures.begin(); it !=this->_futures.end(); ++it) it->cancel(); } 开发者ID:dmerejkowsky,项目名称:libqi,代码行数:7,代码来源:futurebarrier.hpp 示例7: ...
2019-12-15 22:10 −C++11 并发指南五(std::condition_variable 详解) 前面三讲《C++11 并发指南二(std::thread 详解)》,《C++11 并发指南三(std::mutex 详解)》分别介绍了 std::thread,std::mutex,std::future ... 南哥的天下 0 1770 C++11 并发指南三(std::mutex 详解) ...
const std::type_identity_t<Allocator>& alloc ); (since C++23) (10) vector( vector&& other, const Allocator& alloc ); (since C++11) (until C++23) constexpr vector( vector&& other, const std::type_identity_t<Allocator>& alloc ); (since C++23) vector( std::initializer_list<T...
You doreservewhen you just want to preallocate uninitialized memory for future objects. 1 2 3 4 obj z; std::vector<obj> x( 42, z ); std::vector<obj> y; y.resize( 42, z ); Both x and y have 42 valid objects. Value of each object is copied from z. ...
{conststaticstd::vector<std::string> trueValues = {"on","true","yes","1"};conststaticstd::vector<std::string> allValues = {"on","true","yes","1","off","false","no","0"};std::vector<std::string> possible = chooseWord(allValues, message);if(possible.empty())returnfalse;/...