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 (function() {

     var o = {'arguments': 42};

     with (o) { // Definitely forces heavyweight.

         // Note syntax is not a property access.

         reportCompare(delete arguments, true,

                       "arguments property deletion within with block");

     }

     reportCompare('arguments' in o, false,

                   "property deletion observable");

 })();

 (function() {

     var o = {'arguments': 42};

     delete o.arguments;

     reportCompare('arguments' in o, false,

                   "arguments property deletion with property access syntax");

 })();

 (function() {

     var arguments = 42; // Forces heavyweight.

     reportCompare(delete arguments, false,

                   "arguments variable");

 })();

 (function() {

     reportCompare(delete arguments, false, "arguments object");

 })();