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 // Constant folding doesn't affect strict delete either.

 // In particular, it doesn't affect whether |delete x| is a strict error.

 load(libdir + "asserts.js");

 (function (x) {

     "use strict";

     // These senseless delete-expressions are legal even in strict mode.

     // Per ES5.1 11.4.1 step 2, each one does nothing and returns true.

     assertEq(delete (1 ? x : x), true);

     assertEq(delete (0 || x), true);

     assertEq(delete (1 && x), true);

     // Plain `delete x` is a SyntaxError though.

     assertThrowsInstanceOf(() => eval('delete x'), SyntaxError);

     assertThrowsInstanceOf(() => Function('"use strict"; delete x'), SyntaxError);

 }());