Unfortunately, as you noticed, expanding a parameter pack is only valid in certain contexts where the parser expects a comma-separated list of entries – contexts where the comma is just a syntactic separator, not the comma operator. This is arguably a deficiency in the current text. An ugly workaround: func((some(p), 0)…); Do note that the … Read more
The best practice is not to reuse the pool (what would be the use of pooling, if you keep creating new pools?). If you want to be sure you “time” the batches together, I’d suggest using when_all on futures: Live On Coliru #define BOOST_THREAD_PROVIDES_FUTURE_WHEN_ALL_WHEN_ANY #include <iostream> #include <boost/bind.hpp> #include <boost/asio.hpp> #include <boost/thread.hpp> uint64_t foo(uint64_t begin) … Read more
1). Are there any other differences between the two? I find std::atoi() a horrible function: It returns zero on error. If you consider zero as a valid input, then you cannot tell whether there was an error during the conversion or the input was zero. That’s just bad. See for example How do I tell … Read more
That’s a bug, possibly an incomplete port of some library code to cygwin (it’s a cplusplus11 feature) – some stuff has to be changed after all. Make sure to report it. The solution is easy of course: #include <cstdlib> strtol(s.c_str(),0,10); www.cplusplus.com/…/strtol A similar mingw bug is mentioned also here std::stoi doesn’t exist in g++ 4.6.1 … Read more
C++ 11 I think the pertinent part are 3.9.1/1 In C++11 For character types, all bits of the object representation participate in the value representation. For unsigned character types, all possible bit patterns of the value representation represent numbers. These requirements do not hold for other types. Along with 3.9.1/7 The representations of integral types … Read more
The point of having a seed_seq is to increase the entropy of the generated sequence. If you have a random_device on your system, initializing with multiple numbers from that random device may arguably do that. On a system that has a pseudo-random number generator I don’t think there is an increase in randomness, i.e. generated … Read more
http://www.justsoftwaresolutions.co.uk/cplusplus/rvalue_references_and_perfect_forwarding.html Why is this useful? Well, it means that a function template can pass its arguments through to another function whilst retaining the lvalue/rvalue nature of the function arguments by using std::forward. This is called “perfect forwarding”, avoids excessive copying, and avoids the template author having to write multiple overloads for lvalue and rvalue references.
By definition, default initialization is the initialization that occurs when no other initialization is specified; the C++ language guarantees you that any object for which you do not provide an explicit initializer will be default initialized (C++11 §8.5/11). That includes objects of type std::array<T, N> and T[N]. Be aware that there are types for which … Read more
std::weak_ptr is a very good way to solve the dangling pointer problem. By just using raw pointers it is impossible to know if the referenced data has been deallocated or not. Instead, by letting a std::shared_ptr manage the data, and supplying std::weak_ptr to users of the data, the users can check validity of the data … Read more
H2CO3 is right, you can use a makefile with the CXXFLAGS set with -std=c++11 A makefile is a simple text file with instructions about how to compile your program. Create a new file named Makefile (with a capital M). To automatically compile your code just type the make command in a terminal. You may have … Read more