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 // Test that yield* can appear in a loop, and inside yield.

 function* countdown(n) {

     while (n > 0) {

         yield (yield* countdown(--n));

     }

     return 34;

 }

 function collect_results(iter) {

     var ret = [];

     var result;

     do {

         result = iter.next();

         ret.push(result);

     } while (!result.done);

     return ret;

 }

 var expected = [

     // Only 34 yielded from the "yield" and the last return make it out.

     // Three yields in countdown(3), two in countdown(2), and one in

     // countdown(1) (called twice).

     {value: 34, done: false},

     {value: 34, done: false},

     {value: 34, done: false},

     {value: 34, done: false},

     {value: 34, done: false},

     {value: 34, done: false},

     {value: 34, done: false},

     {value: 34, done: true}, // final

 ];

 assertDeepEq(collect_results(countdown(3)), expected);

 if (typeof reportCompare == "function")

     reportCompare(true, true);