javascript - (Why) Can I not throw an exception out of a generator? -

i'm trying throw exception body of es6 generator function, it's not going through. part of es6 specification or quirk of babel?

here code tried (on babeljs.io):

function *gen() {     throw new error('x'); }  try {     gen();     console.log('not throwing'); } catch(e) {     console.log('throwing'); } 

if indeed specified es6 behavior, what's alternative approach signalling exception?

you created iterator didn't run it.

var g = gen(); g.next(); // throws 'x' 

(on babel repl)

here's example:

function *gen() {     (let i=0; i<10; i++) {         yield i;         if (i >= 5)             throw new error('x');     } }  try {     (n of gen())         console.log(n); // throw after `5`     console.log('not throwing'); } catch(e) {     console.log('throwing', e); }