std::result_of 背后的动机是为了确定调用可调用 (Callable) 类型的结果,尤其是结果类型对不同实参集不同的情况。 F(Args...) 是以Args... 为实参类型而以 F 为返回类型的函数类型。因而,std::result_of 承受了许多怪异,导致它在 C++17 中被 std::invoke_result 取代而被弃用: F...
result_ofinvoke_result (C++11)(C++20 移除)(C++17) 推导以一组实参调用一个可调用对象的结果类型 (类模板) thread (C++11) 管理单独的线程 (类) jthread (C++20) 支持自动合并和取消的std::thread (类) call_once (C++11) 仅调用函数一次,即使从多个线程调用 ...
invoke(&Foo::num_, foo) << '\n'; std::cout << "invoke a function object: "; std::invoke(PrintNum(), 18); #if defined(__cpp_lib_invoke_r) auto add = [](int x, int y){ return x + y; }; std::cout << "invoke a lambda converting result to float: "; auto ret = ...
C++11,C++14,C++17,C++20,C++23,C++26│Compiler supportC++11,C++14,C++17,C++20,C++23,C++26 Language Keywords−Preprocessor ASCII chart Basic concepts Comments Names(lookup) Types(fundamental types) Themainfunction Expressions Value categories ...
std::invoke_result_t<std::decay_t<F>const, Args...>>()); (since C++17) (until C++20) template<class...Args> constexprautooperator()(Args&&...args)&& noexcept(/* see below */) ->decltype(!std::invoke( std::declval<std::decay_t<F>>(),std::declval<Args>()...)); ...
MySQL复制是一个非常强大的特性，它允许我们将一个MySQL数据库服务器（主服务器）的数据复制到一个或多...
It can be seen in the program output that .emplace_back doen’t invoke the copy constructor, so it has less overhead than .push_back which copies the passed element.$ clang++ stl-emplace.cpp -o stl-emplace.bin -g -std=c++11 -Wall -Wextra && ./stl-emplace.bin === Experiment .push...
typeChar; 312 case PRIM_INT: return gDvm.typeInt; 313 case PRIM_LONG: return gDvm.typeLong; 314 case PRIM_FLOAT: return gDvm.typeFloat; 315 case PRIM_DOUBLE: return gDvm.typeDouble; 316 default: { 317 ALOGW("Unknown primitive type '%c'", type); 318 return NULL; 319 } 320 } ...
If any A::apply() has a boolean return type and returns false, no further A::apply() calls are made and the result is equivalent to failure, otherwise: Equivalent to success wrt. parsing. Meta data and implementation mapping: apply< A... >::rule_t is internal::apply< A... > ap...
* rather than an offset into clazz->iftable. The invoke-interface 323 * code can test to see if the method returned is abstract or concrete, 324 * and use methodIndex accordingly. I'm not doing this yet because 325 * (a) we waste time in an unusual case, and (b) we're probably...