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 function testUnaryImacros()

 {

   function checkArg(x)

   {

     return 1;

   }

   var o = { valueOf: checkArg, toString: null };

   var count = 0;

   var v = 0;

   for (var i = 0; i < 5; i++)

     v += +o + -(-o);

   var results = [v === 10 ? "valueOf passed" : "valueOf failed"];

   o.valueOf = null;

   o.toString = checkArg;

   for (var i = 0; i < 5; i++)

     v += +o + -(-o);

   results.push(v === 20 ? "toString passed" : "toString failed");

   return results.join(", ");

 }

 assertEq(testUnaryImacros(), "valueOf passed, toString passed");