gistfile1.cpp

// Pointers

int a = 3, b = 4;

int c = 1, d = 2;

int* pa = &a;

int e = *pa;

*pa == a;

pa == &a;

*pa = 2;

a == 2;


// Ignore everything above now
// What comes next has nothing to do with the & that you see above.

int a = 3, b = 4;

int c = 1, d = 2;

int& ra = a;

int e = ra;

ra = 2;

ra == a;

swap_ref(a, b);

a == 4;
b == 3;

void swap_ref(int& v1, int& v2){
    int temp = v1;
    v1 = v2
    v2 = temp;
}

swap_ptr(&c, &d);

void swap_ptr(int* v1, int* v2){
    int temp = *v1;
    *v1 = *v2;
    *v2 = temp;

    int *v3 = v2;
    *v3 = *v2;

    int** v4 = &v3;
    v4 = &v1;
    *v4 = v2;
    **v4 = 5;
}

int x = 5;
int* px = &x;
int** ppx = &px;

*px = 7;
x == 7;


**ppx = 6;
x == 6;


foo(a, b);

void foo(int a, int b){
    //blargh
}

void foo(int& a, int& b){
    //insidious in-place modification of a and b
    a = 7;
    b = 100001;
}

int *p1 = &a;
p1 = &b;

a != b;

int &r1 = a;
r1 = b;

a == b;

// Java

Foo a = new Foo(3);

Foo e = a;
e == a;

e = new Foo(2);

e != a;