getter和setter的`noexcept`说明符

Question

Let's say I have the following code:

class A {
    public:
        void SetInteger(const int val) noexcept { integerMember = val; }
        void SetString(const std::string& val) { stringMember = val; }
        int GetInteger() const noexcept { return integerMember; }
        std::string GetString() const { return stringMember; }

    private:
        int integerMember;
        std::string stringMember;
}

Using noexcept for integral types and pointers seems for me pretty obvious.

But what are recommendations in case of not integral types like classes and structures that do not throw exceptions in constructor/copy-constructor and constructors of their parts explicitly (meaning using throw in constructor body)?

Answer 1

You should avoid noexcept specifiers for functions which may throw (unless you're prepared to have your code call std::terminate() ). Explicit throw specifiers are deprecated, so don't rely on them, rather use the noexcept operator . For example

template<typename T>
class Foo
{
  T m_datum;
public:
  Foo& SetDatum(T const&x) noexcept(noexcept(m_datum=x))
  {
    m_datum = x;
    return *this;
  }
};

Answer 2

Outside of special member functions, noexcept is not that useful. But if you want it:

void SetString(const std::string& val) 
         noexcept(std::is_nothrow_copy_assignable<std::string>::value) {
}

Answer 3

First way for getter:

const std::string& GetString() const noexcept {return stringMember; }

Second way is for setter:

void SetString(std::string&& val) noexcept {
    swap(stringMember, val);
}