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 // Test that each yield* loop just checks "done", and "value" is only

 // fetched once at the end.

 var log = "";

 function collect_results(iter) {

     var ret = [];

     var result;

     do {

         result = iter.next();

         ret.push(result);

     } while (!result.done);

     return ret;

 }

 function Iter(val, count) {

     function next() {

         log += 'n';

         return {

             get done() { log += "d"; return count-- == 0; },

             get value() { log += "v"; return val; }

         }

     }

     function iterator() {

         log += 'i';

         return this;

     }

     this.next = next;

     this[std_iterator] = iterator;

 }

 function* delegate(iter) { return yield* iter; }

 var inner = new Iter(42, 5);

 var outer = delegate(inner);

 // Five values, and one terminal value.

 outer.next();

 outer.next();

 outer.next();

 outer.next();

 outer.next();

 outer.next();

 assertEq(log, "indndndndndndv");

 // Outer's dead, man.  Outer's dead.

 assertDeepEq(outer.next(), {value: undefined, done: true});

 // No more checking the iterator.

 assertEq(log, "indndndndndndv");

 if (typeof reportCompare == "function")

     reportCompare(true, true);