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 function evalWithCache(code, ctx) {

   ctx = ctx || {};

   ctx = Object.create(ctx, {

     fileName: { value: "evalWithCacheCode.js" },

     lineNumber: { value: 0 }

   });

   code = code instanceof Object ? code : cacheEntry(code);

   // We create a new global ...

   if (!("global" in ctx))

     ctx.global = newGlobal();

   // ... and by default enable compileAndGo.

   if (!("compileAndGo" in ctx))

     ctx.compileAndGo = true;

   // Fetch the verification function from the evaluation context.  This function

   // is used to assert the state of the script/function after each run of the

   // evaluate function.

   var checkAfter = ctx.checkAfter || function(ctx) {};

   // The generation counter is used to represent environment variations which

   // might cause the program to run differently, and thus to have a different

   // set of functions executed.

   ctx.global.generation = 0;

   var res1 = evaluate(code, Object.create(ctx, {saveBytecode: { value: true } }));

   checkAfter(ctx);

   ctx.global.generation = 1;

   var res2 = evaluate(code, Object.create(ctx, {loadBytecode: { value: true }, saveBytecode: { value: true } }));

   checkAfter(ctx);

   ctx.global.generation = 2;

   var res3 = evaluate(code, Object.create(ctx, {loadBytecode: { value: true } }));

   checkAfter(ctx);

   ctx.global.generation = 3;

   var res0 = evaluate(code, ctx);

   checkAfter(ctx);

   if (ctx.assertEqResult) {

     assertEq(res0, res1);

     assertEq(res0, res2);

     assertEq(res0, res3);

   }

 }