Second Yield Is Not Working In JavaScript Generator Function

Question

I was learning javascript and if found new concept in function as generator functions As New Feature In ES6

var num=5;
function * x()
{ 
 yield num++;
 yield num*=num; 
};

x().next();

{value: 5, done: false}

x().next();

It Should Return {value: 36, done: false} but returning

{value: 6, done: false} // It Should Return {value: 36, done: false}

• shrys: assign x() to a new variable and then try, a = x(), a.next(), a.next()?
• Mrudul Addipalli: thank you @loganfsmyth

Answer 1

Every call to x() creates a new generator that will start at the beginning, so for

var num=5;
function * x()
{ 
 yield num++;
 yield num*=num; 
};
console.log(x().next());
console.log(x().next());

is essentially identical to doing

var num = 5;
console.log(num++);
console.log(num++);

To get 36, you need to create a single generator and then call next() on it, e.g.

var gen = x();
console.log(gen.next());
console.log(gen.next());