What is `constinit` in C++20?
问题 constinit is a new keyword and specifier in C++20 which was proposed in P1143. The following example is provided in the standard: const char * g() { return "dynamic initialization"; } constexpr const char * f(bool p) { return p ? "constant initializer" : g(); } constinit const char * c = f(true); // OK constinit const char * d = f(false); // ill-formed A few questions come to mind: What does constinit mean? Why was it introduced? In which cases should we use it? Does it make a variable