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 /// Copyright (c) 2012 Ecma International.  All rights reserved. 

 /// Ecma International makes this code available under the terms and conditions set

 /// forth on http://hg.ecmascript.org/tests/test262/raw-file/tip/LICENSE (the 

 /// "Use Terms").   Any redistribution of this code must retain the above 

 /// copyright and this notice and otherwise comply with the Use Terms.

 /**

  * This test is actually testing the [[Delete]] internal method (8.12.8). Since the

  * language provides no way to directly exercise [[Delete]], the tests are placed here.

  *

  * @path ch11/11.4/11.4.1/11.4.1-4.a-9-s.js

  * @description delete operator throws TypeError when deleting a non-configurable data property (Math.LN2) in strict mode 

  * @onlyStrict

  */

 function testcase() {

   'use strict';

   try {

     delete Math.LN2;

     return false;

   }

   catch (e) {

     return (e instanceof TypeError); 

   }

  }

 runTestCase(testcase);