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 // Test adding hooks during dispatch. The behavior is deterministic and "nice",

 // but mainly what we are checking here is that we do not crash due to

 // modifying a data structure while we're iterating over it.

 var g = newGlobal();

 var n = 0;

 var hits;

 function addDebugger() {

     var dbg = new Debugger(g);

     dbg.onDebuggerStatement = function (stack) {

         hits++;

         addDebugger();

     };

 }

 addDebugger();  // now there is one enabled Debugger

 hits = 0;

 g.eval("debugger;");  // after this there are two

 assertEq(hits, 1);

 hits = 0;

 g.eval("debugger;");  // after this there are four

 assertEq(hits, 2);

 hits = 0;

 g.eval("debugger;");  // after this there are eight

 assertEq(hits, 4);

 hits = 0;

 g.eval("debugger;");

 assertEq(hits, 8);