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 // defineProperty can't re-define non-configurable properties.

 // Also: when defineProperty throws, the exception is native to the debugger

 // compartment, not a wrapper.

 var g = newGlobal();

 var dbg = new Debugger;

 var gw = dbg.addDebuggee(g);

 gw.defineProperty("p", {value: 1});

 g.p = 4;

 assertEq(g.p, 1);

 var threw;

 try {

     gw.defineProperty("p", {value: 2});

     threw = false;

 } catch (exc) {

     threw = true;

     assertEq(exc instanceof TypeError, true);

     assertEq(typeof exc.message, "string");

     assertEq(typeof exc.stack, "string");

 }

 assertEq(threw, true);

 assertEq(g.p, 1);