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 // Array.prototype.iterator is generic.

 // That is, it can be applied to arraylike objects and strings, not just arrays.

 load(libdir + "asserts.js");

 load(libdir + "iteration.js");

 function test(obj) {

     var it = Array.prototype[std_iterator].call(obj);

     var ki = Array.prototype.keys.call(obj);

     var ei = Array.prototype.entries.call(obj);

     for (var i = 0; i < (obj.length >>> 0); i++) {

         assertIteratorNext(it, obj[i]);

         assertIteratorNext(ki, i);

         assertIteratorNext(ei, [i, obj[i]]);

     }

     assertIteratorDone(it, undefined);

     assertIteratorDone(ki, undefined);

     assertIteratorDone(ei, undefined);

 }

 test({length: 0});

 test({length: 0, 0: 'x', 1: 'y'});

 test({length: 2, 0: 'x', 1: 'y'});

 test(Object.create(['x', 'y', 'z']));

 test(Object.create({length: 2, 0: 'x', 1: 'y'}));

 test("");

 test("ponies");

 // Perverse length values.

 test({length: 0x1f00000000});

 test({length: -0xfffffffe, 0: 'a', 1: 'b'});

 test({length: "011", 9: 9, 10: 10, 11: 11});

 test({length: -0});

 test({length: 2.7, 0: 0, 1: 1, 2: 2});

 test({length: {valueOf: function () { return 3; }}, 0: 0, 1: 1, 2: 2});