constexpr int f2(NL) { // Error, the parameter type NL is not a literal type. return 55; } constexpr S f3() { return S(); } enum { val = f3() }; // Error, initialization of the return value in f3() // uses a non
例： const int max = 20； // max是常量表达式 const int maxx = max+1； //maxx是常量表达...
constexpr int f5(int x) { // Error, function body contains more than if (x<0) // return statement. x = -x; return x; } When a function template is declared as aconstexprfunction, if the instantiation results in a function that does not satisfy the requirements of aconstexprfunction...
if (is_this_parameter (x)) { if (DECL_CONSTRUCTOR_P (DECL_CONTEXT (x))) { if (flags & tf_error) sorry ("calling a member function of the " "object being constructed in a constant " "expression"); return false; } /* Otherwise OK. */; } else if (!potential_constant_expression...
if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fun) && !DECL_CONSTRUCTOR_P (fun)) { tree x = get_nth_callarg (t, 0); if (is_this_parameter (x)) { if (DECL_CONSTRUCTOR_P (DECL_CONTEXT (x))) { if (flags & tf_error) sorry ("calling a member function of the " ...
exp2(x * x, n / 2) : exp2(x * x, (n - 1) / 2) * x; } // Compile-time computation of array length template<typename T, int N> constexpr int length(const T(&)[N]) { return N; } // Recursive constexpr function constexpr int fac(int n) { return n == 1 ? 1 :...
问在Constexpr函数中使用Reinterpret_CastEN在Python中，format()函数是一种强大且灵活的字符串格式化工具...
Each of its parameter types is a literal type. (until C++23) It is not acoroutine. (since C++20) Its function body is=default,=delete, or a compound statementenclosingonly the following: null statements static_assertdeclarations typedefdeclarations andaliasdeclarations that do not define classes ...
Default use of std::source_location means adding it as a default parameter to the log function. If the log function is a variadic template of the formlog(fmtstr, args...)adding a default parameter is non-trivial. Replacing the macros with constexpr functions makes no sense because ultimately...
static constexpr int ATAN = 14; // get ordinary two-parameter atan static constexpr int HYPOT = 15; // get ordinary two-parameter hypot static constexpr int GROUND_HEIGHT = 16; // get land height, 0 if below water static constexpr int BUILD_PERCENT_LEFT = 17; // get 0 = unit is...