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 // When the debugger is triggered from different stack frames that happen to

 // occupy the same memory, it delivers different Debugger.Frame objects.

 var g = newGlobal();

 var dbg = Debugger(g);

 var hits;

 var a = [];

 dbg.onDebuggerStatement = function (frame) {

     for (var i = 0; i < a.length; i++) 

         assertEq(a[i] === frame, false);

     a.push(frame);

     hits++;

 };

 g.eval("function f() { debugger; }");

 g.eval("function h() { debugger; f(); }");

 hits = 0;

 g.eval("for (var i = 0; i < 4; i++) h();");

 assertEq(hits, 8);