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 // Each resumption of a generator gets a fresh frame, whose onPop handler

 // fires the next time the generator yields.

 // This is not the behavior the spec requests, but it's what we do for the

 // moment, and it's good to check that at least we don't crash.

 var g = newGlobal();

 var dbg = new Debugger(g);

 var log;

 var debuggerFrames = [];

 var poppedFrames = [];

 dbg.onDebuggerStatement = function handleDebugger(frame) {

     log += 'd';

     assertEq(frame.type, "call");

     assertEq(debuggerFrames.indexOf(frame), -1);

     assertEq(poppedFrames.indexOf(frame), -1);

     debuggerFrames.push(frame);

     if (frame.eval('i').return % 3 == 0) {

         frame.onPop = function handlePop(c) {

             log += ')' + c.return;

             assertEq(debuggerFrames.indexOf(this) != -1, true);

             assertEq(poppedFrames.indexOf(this), -1);

             poppedFrames.push(this);

         };

     }

 };

 g.eval("function g() { for (var i = 0; i < 10; i++) { debugger; yield i; } }");

 log ='';

 assertEq(g.eval("var t = 0; for (j in g()) t += j; t;"), 45);

 assertEq(log, "d)0ddd)3ddd)6ddd)9");