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c++stringc++11stdstring

what is the meaning of this std::string constructor

Today I tried to study some piece of code and I am stuck with this line.

std::vector<std::string(SomeClassInterface::*)()> ListOfFnPointers;

what is the meaning of this std::string constructor? I went through this but I have no idea what it means.

It is used in the code as,

if (!ListOfFnPointers.empty())
{
    std::vector<std::string> StringList;
    for (auto Fn : ListOfFnPointers)
    {
        StringList.push_back((pSomeClassObj->*Fn)());
    }
    ...
}
  1. What that declaration means?
  2. what exactly this function doing with pSomeClassObj->*Fn?
Solution

  • It has nothing to do with std::string constructor.

    std::string(SomeClassInterface::*)() is type of pointer to member function, the member function belongs to class SomeClassInterface, returns std::string, takes no parameters.

    ->* is pointer-to-member access operator (and also .*). (pSomeClassObj->*Fn)() will call the member function on pSomeClassObj, which is supposed to be a pointer with type SomeClassInterface*.