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 // After an implicit toString call throws an exception, the calling frame's

 // onStep hook fires.

 var g = newGlobal();

 g.eval("var x = {toString: function () { debugger; log += 'x'; throw 'mud'; }};");

 var dbg = Debugger(g);

 dbg.onDebuggerStatement = function (frame) {

     g.log += 'd';

     frame.older.onStep = function () {

         if (!g.log.match(/[sy]$/))

             g.log += 's';

     };

 };

 g.log = '';

 g.eval("try { x + ''; } catch (x) { }\n" +

        "log += 'y';\n");

 assertEq(g.log, "dxsy");

 g.log = '';

 g.eval("try { '' + x; } catch (x) { }\n" +

        "log += 'y';\n");

 assertEq(g.log, "dxsy");