#include using namespace std; /* written by AZTECCO * * premise: * The difference between pointers * and references is not so simple * * happens many times i have to * explain it, so i written this * for reusage, that's all. * * There are many programmers better * than me, so if you think there's * something wrong or to add * please comment indicating the line * and i will edit, and give credit. * Thanks! */ int main() { // VARIABLE AND REFERENCE /* A reference is not a variable, a pointer is. Variable: you can change its value, so you can change the address a pointer points to. Reference: is an alias for one and only one variable during its lifetime. cannot be assigned to a different variable. Must be defined at declaration time. Act as the real variable. A variable is identified by: 1-variable name 'x' 2-address usually hex '0xfa0b4...' 3- and references: like a nikname, it will be given after the birthname * a variable can have only one name and one address but many references * a pointer stores an address */ int x, y=99, z=y; // some data // * * * DECLARE * * * int* p; // pointer // int& ref2; // this will give an error! try to uncomment int& ref=x; // reference // * * * ASSIGN * * * p = &x; // a pointer receive an ADDRESS *p = 1; // ASSIGN VALUE to x trough pointer, we are not assigning to the pointer itself. // note the dereference operator * cout<<"#1 : " << *p < why using reference? * references have a simplier syntax(less bugs). * value guaranteed: using references as parameters stops empty arguments, instead, you can pass a null pointer. * references are necessary to define copy constructors. * are necessary for operator overloads. * const references allow you to have pass-by-value semantics while avoiding a copy. */ /* => why using pointers? because you have to. guarantee NOT WANTED: you can pass an empty pointer, but you have to handle it. */ /* rule of thumb: ALWAYS PASS BY REFERENCE. PASS BY POINTER ONLY IF YOU HAVE TO. */ return 0; }

pointers Vs references