constexpr是对象或者函数接口的一部分，所以如果你使用了constexpr但反悔了，移除constexpr可能会导致大量的...
Aconstexprintegral value can be used wherever a const integer is required, such as in template arguments and array declarations. And when a value is computed at compile time instead of run time, it helps your program run faster and use less memory. ...
constexpr不是对象类型的一部分，无论对static T data_member用const还是constexpr，他的类型都是const ...
Unlike const, constexpr can also be applied to functions and class constructors. constexpr indicates that the value, or return value, is constant and, where possible, is computed at compile time.A constexpr integral value can be used wherever a const integer is required, such as in template...
template <class C> constexpr NL f6(C c) { // OK, the constexpr specifier ignored return NL(); } void g() { f6(55); // OK, not used in a constant expression } A call to aconstexprfunction produces the same result as a call to an equivalent non-constexprfunction in all respec...
template <class C> constexpr NL f6(C c) { // OK, the constexpr specifier ignored return NL(); } void g() { f6(55); // OK, not used in a constant expression } A call to aconstexprfunction produces the same result as a call to an equivalent non-constexprfunction in all respec...
classPoint{public:constexprPoint(doublexVal,doubleyVal)noexcept:x_{xVal},y_{yVal}{}constexprdoublexValue()constnoexcept{returnx_;}constexprdoubleyValue()constnoexcept{returny_;}constexprvoidsetX(doublexNew)noexcept{x_=xNew;}// C++14 onlyconstexprvoidsetY(doubleyNew)noexcept{y_=yNew;}//...
For constexpr function templates and constexpr member functions of class templates, at least one specialization must satisfy the abovementioned requirements. Other specializations are still considered as constexpr, even though a call to such a function cannot appear in a constant expression. ...
class T { public: T(int _n): n(_n){} int geti()const{return n;} private: int n; }; void fun(T &t) { cout<<t.geti()<<endl; } int main() { fun(100); return 0; } === constexpr和const数组的区别 const是表bai明这个值是constant的,但是不必在编译du期确定,然而数...
classPoint{public:constexprPoint(doublexVal,doubleyVal)noexcept:x_{xVal},y_{yVal}{}constexprdoublexValue()constnoexcept{returnx_;}constexprdoubleyValue()constnoexcept{returny_;}constexprvoidsetX(doublexNew)noexcept{x_=xNew;}// C++14 onlyconstexprvoidsetY(doubleyNew)noexcept{y_=yNew;}//...