for example what does the for (;;) {} do here? which means the ;; inside the for?
double parseExpression() {
double x = parseTerm();
for (;;) {
if (eat('+')) x += parseTerm(); // addition
else if (eat('-')) x -= parseTerm(); // subtraction
else return x;
}
}
The use of ;; in the declaration of your loop, makes it infinite; look at the next couple of examples
INFINITE LOVERS
Through the following example, you can observe that it is to declare an infinite loop; you are not declaring neither the variable that is going to be used nor the counter, much less the limit to be respected.
public class MyClass {
public static void main(String args[]) {
for(;;)
{
System.out.println("Hola");
}
}
}
You can also see it in the following way, you declare the variable to use and an initial value and then the increase counter and the same will be infinite
public class MyClass {
public static void main(String args[]) {
for(int numero = 0;;numero++)
{
System.out.println(numero);
}
}
}