A first vala example

example1.vala

// Take for example the following methods:

void method_1(int a, out int b, ref int c) {
  //implementation
}
void method_2(Object o, out Object p, ref Object q) {
  //implementation
}

// Which are later called with values

int a = 1;
int b;
int c = 3;
method_1(a, out b, ref c);

Object o = new Object();
Object p;
Object q = new Object();
method_2(o, out p, ref q);

// Possible implementation of method1
void method_1(int a, out int b, ref int c) {
    b = a + c;
    c = 3;
}