CppCoreGuidelines F.9 不用给没有用到的参数命名

// once upon a time, a hint was used
X* find(map<Blob>& m, const string& s, Hint);

void print_params(const int i, const string& s, double) {
    cout << i << " " << s << endl;
}

int main()
{
    print_params(10, "hello", 1.1);
    return 0;
}

template <typename Value>
Value* find(const set<Value>& s, const Value& v, [[maybe_unused]] Hint h)
{
    if constexpr (sizeof(Value) > CacheSize)
    {
        // a hint is used only if Value is of a certain size
    }
}