private-members

问题 I asked another question before about how to access a global variable in Swift, but realized the global variable did not work for my purposes. Some background: The game is a math/match game. Player's will have an equation, and they have to get the sheep with the matching answer. I have sheep that spawn on screen. Each sheep holds a unique int value (1-12) that is generated within my spawnSheep method: var sheepValue: Int = Int(arc4random_uniform(UInt32(12))+1) Multiple sheep will spawn on

问题 I am trying to use the following line to specify a double constant, can anybody help explain to me why at runtime this constant has a value of 0.0 : private static final double CONSTANT = 1/2; 回答1: 1 and 2 are interpreted as integers and produce integer result of division. Add D at the end to make them interpreted as doubles. private static final double CONSTANT = 1D/2D; 回答2: The constant ends up with a value of 0.0 because the result of integer division is an integer, truncated. So your the

问题 I would like to get private properties of the class using TypeDescriptor in c#. So far calling TypeDescriptor.GetProperties(myType); returns only public, non-static properties. I have not found a way how to influence GetProperties or GetProvider methods to force them to return other than "default" (public, non-static) members. Please do not suggest reflection (I am well aware of BindingFlags) unless it gives me a PropertyDescriptor object. 回答1: To do that you would have to write and register

问题 I have a pointer to a list of pointers, as a private variable. I also have a getter that returns the pointer to the list. I need to protect it from changes. I couldn't find how to use reinterpret_cast or const_cast on this. class typeA{ shared_ptr<list<shared_ptr<typeB>>> l; public: shared_ptr<list<shared_ptr<const typeB>>> getList(){return (l);}; }; The compiler returns: error: could not convert ‘((typeA*)this)->typeA::x’ from ‘std::shared_ptr<std::__cxx11::list<std::shared_ptr<typeB> > >’

问题 Why does this happen? http://coliru.stacked-crooked.com/a/e1376beff0c157a1 class Base{ private: virtual void do_run() = 0; public: void run(){ do_run(); } }; class A : public Base { public: // uplift ?? virtual void do_run() override {} }; int main() { A a; a.do_run(); } Why can I override a PRIVATE virtual method as public? 回答1: According to https://en.cppreference.com/w/cpp/language/virtual#In_detail overwriting a base's virtual member function only care about the function name, parameters,

问题 Since I'm a newbie in C++, here it goes! I have a base class (I'm not using inheritance anywhere) with two objects from two other classes. I need to have access from a private member to the other in another class. class base { private: myClass1 m1; myClass2 m2; public: base() {}; ~base() {}; }; class myClass1 { private: int m_member1; public: myClass1() {}; ~myClass1() {}; }; class myClass2 { private: int m_member2; public: myClass2() {}; ~myClass2() {}; int sum_members_because_yes(void) {

问题 I need to make t static to each thread, how can I do that? I tried this but t is not static private to each thread. #pragma omp Parallel { traceRays(); } ... ... void traceRays() { static float t = 1; } 回答1: if the static variable is not declared in the parallel region, then everytime you attempt to define in the parallel region use: #omp parallel private(t) 回答2: You can do it by just making t threadprivate: void traceRays() { static float t = 1; #pragma omp threadprivate(t) } 来源： https:/

问题 I have a public property (AllCustomers), which is backed by a private property for lazy loading. I understand that the public property should be IEnumerable ("program to interfaces, not implementations"). However, I can see two ways to build the private property. First option, with private List- private List<Customer> _AllCustomers; public IEnumerable<Customer> AllCustomers { get { if (_AllCustomers == null) { _AllCustomers = DAL.GetAllCustomers().ToList(); } return _AllCustomers; } } Second

问题 In a method of my class MyHeader i access the private property _label of another MyHeader object new_header : class MyHeader: def __init__(self, label, n_elem): self._label = label self._n_elem = n_elem def check_header_update(self, new_header): # check that label is preserved if new_header._label != self._label: raise Exception("new header must have the same label") In PyCharm, this results in the syntax highlighting error " Access to a protected member _label of a class ". I tried

问题 I have some understanding of the difference between private members and let bindings. It may help me clarify my doubts understanding why something like this is not possible type B () = inherit A () let doSomething () = base.CallToA () Is it to prevent partially constructed objects or some leaks during construction? 回答1: The base keyword is only really needed to call a base-class implementation of a virtual method. That is the only case where you need base because you cannot invoke the method