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 // A Map iterator does not visit entries removed by clear().

 load(libdir + "iteration.js");

 var m = Map();

 var it = m[std_iterator]();

 m.clear();

 assertIteratorDone(it, undefined);

 m = Map([["a", 1], ["b", 2], ["c", 3], ["d", 4]]);

 it = m[std_iterator]();

 assertIteratorNext(it, ["a", 1]);

 m.clear();

 assertIteratorDone(it, undefined);

 var log = "";

 m = Map([["a", 1], ["b", 2], ["c", 3], ["d", 4]]);

 for (var [k, v] of m) {

     log += k + v;

     if (k == "b")

         m.clear();

 }

 assertEq(log, "a1b2");