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 // The value of frame.environment is the same Environment object at different

 // times within a single visit to a scope.

 var g = newGlobal();

 var dbg = Debugger(g);

 g.eval("function h() { debugger; }");

 var hits, env;

 dbg.onDebuggerStatement = function (hframe) {

     var frame = hframe.older;

     var e = frame.environment;

     // frame.environment is at least cached from one moment to the next.

     assertEq(e, frame.environment);

     // frame.environment is cached from statement to statement within a call frame.

     if (env === undefined)

         env = e;

     else

         assertEq(e, env);

     hits++;

 };

 hits = 0;

 env = undefined;

 g.eval("function f() { (function () { var i = 0; h(); var j = 2; h(); })(); }");

 g.f();

 assertEq(hits, 2);

 hits = 0;

 env = undefined;

 g.eval("function f2() { { let i = 0; h(); let j = 2; h(); } }");

 g.f2();

 assertEq(hits, 2);

 hits = 0;

 env = undefined;

 g.eval("function f3() { { let i; for (i = 0; i < 2; i++) h(); } }");

 g.f3();

 assertEq(hits, 2);