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 // Test that a deep yield* chain re-yields received results without

 // re-boxing.

 function results(results) {

     var i = 0;

     function next() {

         return results[i++];

     }

     var iter = { next: next };

     var ret = {};

     ret[std_iterator] = function () { return iter; }

     return ret;

 }

 function* yield_results(expected, n) {

     return yield* n ? yield_results(expected, n - 1) : results(expected);

 }

 function collect_results(iterable) {

     var ret = [];

     var result;

     var iter = iterable[std_iterator]();

     do {

         result = iter.next();

         ret.push(result);

     } while (!result.done);

     return ret;

 }

 // We have to put a full result for the end, because the return will re-box.

 var expected = [{value: 1}, 13, "foo", {value: 34, done: true}];

 assertDeepEq(expected, collect_results(results(expected)));

 assertDeepEq(expected, collect_results(yield_results(expected, 20)));

 if (typeof reportCompare == "function")

     reportCompare(true, true);