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 // addDebuggee, hasDebuggee, and removeDebuggee all throw if presented with

 // objects that are not valid global object designators.

 load(libdir + 'asserts.js');

 var dbg = new Debugger;

 function check(bad) {

   print("check(" + uneval(bad) + ")");

   assertThrowsInstanceOf(function () { dbg.addDebuggee(bad); }, TypeError);

   assertEq(dbg.getDebuggees().length, 0);

   assertThrowsInstanceOf(function () { dbg.hasDebuggee(bad); }, TypeError);

   assertThrowsInstanceOf(function () { dbg.removeDebuggee(bad); }, TypeError);

 }

 var g = newGlobal();

 check(g.Object());

 check(g.Object);

 check(g.Function(""));

 // A Debugger.Object belonging to a different Debugger is not a valid way

 // to designate a global, even if its referent is a global.

 var g2 = newGlobal();

 var dbg2 = new Debugger;

 var d2g2 = dbg2.addDebuggee(g2);

 check(d2g2);