c++11 - What all operators can be defined inside a struct in C++? -

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• what basic rules , idioms operator overloading? 7 answers

i cannot understand 3rd,4th line in following code in c++ :

struct point {       int x,y;       point(int x = 0, int y = 0) : x(x), y(y) {}       bool operator ==(point& a) {return a.x==x && a.y==y;} }; 

other examples/explanations welcome apart code snippet :)

structure nothing class data members , functions defined in public scope. can implement operators valid class.

if question on operator overloading, overloaded operators can defined class valid structure.

you can refer operator overloading question , answer understand more on operator overloading

point(int x = 0, int y = 0) : x(x), y(y) {} //(3rd line) bool operator ==(point& a) {return a.x==x && a.y==y;}//(4th line) 

3rd line constructor, , 4th line operator overloading function operator ==.

point p1(2,3); // 3rd line called , update x=2 , y=3

point p2; // 3rd line called , consider x=0 , y=0            //since function definitiion defaulted value x=0 , y=0; if(p2==p1) {....}   // 4th line called , compare p1 , p2