例： const int max = 20； // max是常量表达式 const int maxx = max+1； //maxx是常量表达...
A non-formal description of a constant expression could be: Given compile time input, the constant expression can compute the result. For a variable, it's pretty straightforward. You set the value at compile time, you have the result at compile time. In C++ 14 (and also C++ 11 actually,...
A non-formal description of a constant expression could be: Given compile time input, the constant expression can compute the result. For a variable, it's pretty straightforward. You set the value at compile time, you have the result at compile time. In C++ 14 (and also C++ 11 actually,...
constexpr表示值或者返回值是常量，并且如果可能，在编译时计算它们。constexpr和const的主要区别是const变...
ENconst类型变量 --- int i; const int *p; --- int i; int *const p = &i; --...
};/*constexpr variable 'g_PERT_S1' must be initialized by a constant expression non-constexpr function 'data' cannot be used in a constant expression array(226): declared here*/constexprarray<ELPMPP02Pertubations, 4> g_PERT_S1/*ERROR HERE*/{ { ...
First, use ofconstdoes not make it immediately clear whether the variable is usable in a constant expression or not. In some cases, we can figure it out fairly easily: inta{5};// not const at allconstintb{a};// clearly not a constant expression (since initializer is non-const)constin...
'c' must be initialized by a constant expressionb=5;//error! Cannot assign to variable 'b' ...
begin1.csh: begin1.csh: 0:441(28): error: initializer of const variable `worldSunColor' must be a constant expression 0:442(32): error: initializer of const variable `worldHorizonColor' must be a constant expression 0:443(29): error: initializer of const variable `worldMoonColor' must ...
Defines an expression that can be evaluated at compile time. Such expressions can be used as non-type template arguments, array sizes, and in other contexts that require constant expressions. If you have a constant integral variable that isconstinitialized, or enumeration value, then it can be ...