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 // Destructuring arguments.

 var g = newGlobal();

 var dbg = new Debugger(g);

 var hits = 0;

 dbg.onDebuggerStatement = function (frame) {

     var args = frame.arguments;

     assertEq(args[0], 1);

     assertEq(args.length, 4);

     assertEq(args[1] instanceof Debugger.Object, true);

     assertEq(args[1].class, "Array");

     var getprop = frame.eval("(function (p) { return this[p]; })").return;

     assertEq(getprop instanceof Debugger.Object, true);

     assertEq(getprop.apply(args[1], ["length"]).return, 2);

     assertEq(getprop.apply(args[1], [0]).return, 2);

     assertEq(getprop.apply(args[1], [1]).return, 3);

     assertEq(args[2] instanceof Debugger.Object, true);

     assertEq(args[2].class, "Object");

     var x = getprop.apply(args[2], ["x"]).return;

     assertEq(x.class, "Array"); 

     assertEq(getprop.apply(x, ["0"]).return, 4);

     assertEq(getprop.apply(args[2], ["z"]).return, 5);

     assertEq(args[3] instanceof Debugger.Object, true);

     assertEq(args[3].class, "Object");

     assertEq(getprop.apply(args[3], ["q"]).return, 6);

     hits++;

 };

 g.eval("function f(a, [b, c], {x: [y], z: w}, {q}) { debugger; }");

 g.eval("f(1, [2, 3], {x: [4], z: 5}, {q: 6});");

 assertEq(hits, 1);