c++11 - C++ object instantiations -

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• default constructor empty brackets 8 answers

this question object instantiations in c++. there several ways instantiate objects both on heap , on stack curious know subtle differences.

using namespace std;  class raisin { private:     int x; public:     raisin():x(3){}     raisin(int input):x(input){}     void printvalue()     {        cout<< "hey deliciousness is: " << x <<endl;     } }; 

basically raisin simple class using demonstration:

int main() {  raisin * a= new raisin; a->printvalue();  raisin * b= new raisin{}; b->printvalue();  raisin * c= new raisin(); c->printvalue();  raisin x; x.printvalue();  raisin y{}; y.printvalue();  raisin z(); z.printvalue();  //error: request member 'printvalue' in 'z',  //which of non-class type 'raisin()'   raisin alpha(12); alpha.printvalue();  raisin omega{12}; omega.printvalue();  return 0; } 

i know why raisin * c can instantiated empty parenthesis, raisin z cannot be. (actually raisin z() legal incorrect)

also understand there subtle difference between raisin (2) , raisin{2}. appreciate if can shed light on idiosyncrasies.

this line

raisin z(); 

declares function (with no argument) returning raisin object, not default-constructed raisin