Cpp Coding Standards

哲学与接口 (P.*, I.*)

关键规则

应该做

// P.10 + I.4: Immutable, strongly typed interface
struct Temperature {
    double kelvin;
};

Temperature boil(const Temperature& water);

不应该做

// Weak interface: unclear ownership, unclear units
double boil(double* temp);

// Non-const global variable
int g_counter = 0;  // I.2 violation

函数 (F.*)

关键规则

参数传递

// F.16: Cheap types by value, others by const&
void print(int x);                           // cheap: by value
void analyze(const std::string& data);       // expensive: by const&
void transform(std::string s);               // sink: by value (will move)

// F.20 + F.21: Return values, not output parameters
struct ParseResult {
    std::string token;
    int position;
};

ParseResult parse(std::string_view input);   // GOOD: return struct

// BAD: output parameters
void parse(std::string_view input,
           std::string& token, int& pos);    // avoid this

纯函数和 constexpr

// F.4 + F.8: Pure, constexpr where possible
constexpr int factorial(int n) noexcept {
    return (n <= 1) ? 1 : n * factorial(n - 1);
}

static_assert(factorial(5) == 120);

反模式

• 从函数返回 T&& (F.45)
• 使用 va_arg / C 风格可变参数 (F.55)
• 在传递给其他线程的 lambda 中通过引用捕获 (F.53)
• 返回 const T，这会抑制移动语义 (F.49)

类与类层次结构 (C.*)

关键规则

零规则

// C.20: Let the compiler generate special members
struct Employee {
    std::string name;
    std::string department;
    int id;
    // No destructor, copy/move constructors, or assignment operators needed
};

五规则

// C.21: If you must manage a resource, define all five
class Buffer {