c++14

I want to implement a small thread wrapper that provides the information if a thread is still active, or if the thread has finished its work. For this I need to pass the function and its parameters to be executed by the thread class to another function. I have a simple implementation that should work but cannot get it to compile, and I can't figure out what to do to make it work. Here is my code: #include <unistd.h> #include <iomanip> #include <iostream> #include <thread> #include <utility> class ManagedThread { public: template< class Function, class... Args> explicit ManagedThread( Function&

So I have an std::string and have a function which takes char* and writes into it. Since std::string::c_str() and std::string::data() return const char* , I can't use them. So I was allocating a temporary buffer, calling a function with it and copying it into std::string . Now I plan to work with big amount of information and copying this buffer will have a noticeable impact and I want to avoid it. Some people suggested to use &str.front() or &str[0] but does it invoke the undefined behavior? C++98/03 Impossible. String can be copy on write so it needs to handle all reads and writes. C++11/14

Is it possible to write C++ code where we rely on the return value optimization (RVO) when possible, but fall back on move semantics when not? For example, the following code can not use the RVO due to the conditional, so it copies the result back: #include <iostream> struct Foo { Foo() { std::cout << "constructor" << std::endl; } Foo(Foo && x) { std::cout << "move" << std::endl; } Foo(Foo const & x) { std::cout << "copy" << std::endl; } ~Foo() { std::cout << "destructor" << std::endl; } }; Foo f(bool b) { Foo x; Foo y; return b ? x : y; } int main() { Foo x(f(true)); std::cout << "fin" << std

Trying to create a way to identify if a given class has a given function that can be invoked, and returns some type. Any idea on what I'm doing wrong here? Is there a better way to determine if a given method is invoke'able given a class? #include <string> #include <type_traits> #define GENERATE_HAS_MEMBER_FUNC(func, rettype) \ template<typename T, class Enable = void> struct has_##func; \ template<typename T, class U> struct has_##func : std::false_type {}; \ template<typename T> \ struct has_##func<T, \ typename std::enable_if<std::is_same< \ typename std::result_of<decltype (&T::func)(T)>:

I have base object called IList . Then I have VectorList , that inherits IList . then I have function like this: std::unique_ptr<IList> factory(){ auto vlist = std::make_unique<VectorList>(); return vlist; } This compiles without problem under gcc , but clang gives following error: test_file.cc:26:9: error: no viable conversion from 'unique_ptr<VectorList, default_delete<VectorList>>' to 'unique_ptr<IList, default_delete<IList>>' return vlist; How is proper way to handle this kind of errors? It appears (your version of) Clang is still following C++11 behaviour in this regard. In C++11, you had

I'm trying to see if this is possible in the C++14 generic lambda, but I cannot find a right way to express it (or perhaps it is not possible). The simplified example is: auto confirmOperation = [](auto pr){ assert(pr.second); }; The idea is that if you pass it an std::pair where the second is a bool (such as what is returned from emplace functions), it can look at this bool. If this was a template parameter instead, I could explicitly show the pair with the types of the pair as generic, but I don't think that is possible with a lambda? Thus instead I mark the entire argument as generic, and

I am using variadic parameter packs for policy based class design. template <APITypes APIType, class... Policies> class IShader : public Policies... { }; Policies are defined when called or with defaults if none are specified. The problem comes when I need to add another variadic parameter pack: template <AttributeType... Attributes, APITypes APIType, class... Policies> class IShader : public Policies... { }; This results in the error "Template parameter pack must be the last template parameter". I am planning to use the attribute pack to change the behaviour of at least one of the policies.