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 // A closure's .environment keeps the lexical environment alive even if the closure is destroyed.

 var N = 4;

 var g = newGlobal();

 g.eval("function add(a) { return function (b) { return eval('a + b'); }; }");

 var dbg = new Debugger;

 var gw = dbg.addDebuggee(g);

 var aw = gw.getOwnPropertyDescriptor("add").value;

 // Create N closures and collect environments.

 var arr = [];

 for (var i = 0; i < N; i++)

     arr[i] = aw.call(null, i).return.environment;

 // Test that they work now.

 function check() {

     for (var i = 0; i < N; i++) {

         assertEq(arr[i].find("b"), null);

         assertEq(arr[i].find("a"), arr[i]);

     }

 }

 check();

 // Test that they work after gc.

 gc();

 gc({});

 g.gc(g);

 check();